Substitutes for Potent Greenhouse Gases
(HFCs, PFCs and SF6)
1998
Final Report
Per Henrik Pedersen
MSc.Eng
Danish Technological Institute
Energy
DTI Energy
P.O. Box 141
DK-2630 Taastrup
Tel.: +45 43 50 45 23
Fax: +45 43 50 72 22
E-mail: Per.Henrik.Pedersen@dti.dk
Contents
Preface
1 Background
2 Aim of project and organisation
3 Application of HFC substances and possible
alternatives
3.1 Refrigeration industry
3.1.1 Domestic refrigerators and freezers
3.1.2 Commercial refrigerators and freezers
3.1.3 Commercial refrigeration systems
3.1.4 Industrial refrigeration plants
3.1.5 Mobile refrigeration systems
3.1.6 Heat pumps
3.1.7 Air-conditioning systems
3.1.8 Cryogenic systems
3.2 Polyurethane foam
3.2.1 Insulating foam
3.2.2 Jointing foam
3.2.3 Flexible polyurethane foam
3.3 Fire extinguishants
3.4 Propellant in aerosol cans and foghorns
3.5 Other fields of application
4 Use of PFC substances
4.1 PFC in refrigerant mixtures
4.2 Other applications of PFC substances
5 Consumption of SF6 and substitution possibilities
5.1 Noise-reducing double glazed windows
5.2 Protective gases in light-metal foundries
5.3 Insulating gas in electric power switches
5.4 Tracer gas and other laboratory purposes
5.5 Car tyres
5.6 Other possible applications of SF
6 Evaluations and recommendations
7 Project proposals for the Cleaner Technology programme
8 Literature
Appendix A: List over refrigerants and refrigerant
mixtures
Appendix B: Commercial refrigeration systems
Appendix C: Sabroe Chillers with NH3-refrigerant, installed
in Denmark 1990-1998
Appendix D: Gram Chillers (York International) with NH3
refrigerant, installed in Denmark 1992-1998
Appendix E: Bonus Chillers with Hydrocarbon-refrigerant,
installed in Sweden 1996-1998
Preface
In recent years, the consumption of potent greenhouse gases in Denmark has increased, whilst at the same time the consumption of CFCs, HCFCs and other substances, depleting the ozone layer, is approaching zero.
Especially the consumption of HFC-substances has increased. These substances are used as substitutes for CFCs and HCFCs for certain purposes, especially for refrigeration and blowing of polyurethane foam. However, it should be mentioned that more environmentally friendly alternatives have been introduced, e.g. hydrocarbons in aerosol cans, cyclopentane for district heating pipes and hydrocarbons, ammonia and water in various types of refrigeration systems.
CFCs (halogenated chlorofluorocarbons), HCFCs
(hydrochlorofluorocar-
bons), HFCs (hydrofluorocarbons), PFCs (fluorocarbons) and
SF6 (sulphur hexafluoride) are all artificial substances
which were not to be found in nature until recently.
Furthermore, as these substances are relatively stable,
their lifetime in the atmosphere is long. This applies
particularly to the fully halogenated substances: CFCs, PFCs
and SF6. The CFCs and HCFCs are ozone depleting substances,
which are subjected to an international convention, the
Montreal Protocol, for guarantee of elimination of these
substances. Except essential uses, Danish and EU legislation
has now prohibited the use of CFCs. Additionally, the use of
HCFC is decreasing in Denmark and will be brought to a
complete stop before year 2002. After December 31st 1999,
the erection of new plants using HCFC is forbidden.
Because HFCs, PFCs and SF6 contain neither chlorine nor
bromide, these substances will not contribute to any
depletion of the ozone layer. However, they contribute to
the greenhouse effect. The United Nation Climate Convention
conducted the regulation of greenhouse gases. The substances
have been included in the list of greenhouse gases (in the
Kyoto Protocol) and the countries have to reduce the
emission of them. The substances are regarded as comparable
to carbon dioxide (CO2), methane (CH4) and nitrous oxide
(N2O).
In 1997, Danish consumption of HFC substances amounted to
app. 890 tonnes, where the corresponding amount of SF6 was
app. 13 tonnes. If the entire amount of these substances was
released to the atmosphere, the resulting impact would
correspond to an increased emission of greenhouse gases,
corresponding to app. 1.6 million tonnes of CO2 (the
contribution would be 78% from the HFC substances, 18% from
SF6 and 3% PFC). That corresponds to app. 3% of the Danish
CO2 emission (57.3 million tonnes in 1997). In addition,
some of the substances have a very long life in the
atmosphere.
This it the reason why the Council for Re-use and Less
Polluting Technologies has supported this project
financially.
According to experience from the CFC programme it is
possible to recover some CFC and send it to controlled
destruction. From 1993 to 1996 the refrigeration industry,
for instance, has returned a total amount of 163 tonnes of
CFC refrigerant through the KMO organisation (Danish
refrigeration industy's recovery and recycling scheme). Most
of this has been destroyed and a small amount has been
purified and recycled afterwards. Similarly, it must be
expected that some HFC refrigerants will be returned through
the KMO organisation.
However, the recharge of refrigerant mixtures in the R400
series will involve certain difficulties as the original
concentration of the mixture might have changed.
At an international conference for natural refrigerants held
in September 1996, the Danish Minister of Environment and
Energy, Mr. Svend Auken, proclaimed that an environmental
phase-out strategy would be initiated for HFCs and other
potent greenhouse gases in Denmark within a period of 10
years. At the same time, he asked the Danish Environmental
Protection Agency (the Danish EPA) to investigate how the
phase-out strategy could be carried out and also to initiate
discussions about this topic with industry and the green
organisations. This report forms part of the basis for the
further discussion.
In addition, HFCs, PFCs and SF6 are registered on the Danish
EPA's list of non-desirable substances. It was published as
an official list in 1998 (Environmental Review No. 7, Danish
Environmental Protection Agency, 1998).
In recent years, various technologies have been discussed at
conferences and seminars, in technical magazines and in
daily newspapers. Many questions have been asked about how
to find the most suitable techno-logy that is
environmentally safe and safe to use. Examples are modern
household refrigerators using two kinds of refrigerants,
viz. HFC-134a and hydrocarbon (isobutane).
Such discussions will presumably continue many years from
now. It is not only a discussion between industry on the one
side and green organisations on the other. It is to a high
degree a discussion among people within different industrial
trades and the discussions are often influenced by
commercial considerations.
The Energy Division at Danish Technological Institute (DTI
Energy) is aware that this report might be used as reference
in such discussions. The steering committee, established by
the Danish EPA on the basis of this project, consists of
members representing both industry and green
organisations.
The Danish EPA has assessed that matters related to this
project shall be discussed freely in order to allow the
members of the steering committee and their respective
organisations to contribute with further information. DTI
Energy will then attempt to depict all relevant and factual
information.
However, development continually takes place within the
various technological areas mentioned in this report.
Therefore, some of the information will quickly become
obsolete. Finally, there might be information DTI has no
knowledge of and therefore it has not been mentioned in this
report.
1 Background
In 1997, Danish industry utilised app. 890 tonnes of
HFCs, app. 13 tonnes of SF6 and app. 8 tonnes of PFCs.
The table below shows consumption and the environmental
effects from using the substances.
|
Sub- |
Consumption in 1997, |
GWP |
CO2 |
Atmospheric Life Time, (in yrs) |
|
HFC-134a |
700 |
1300 |
910.000 |
14.6 |
|
HFC-152a |
15 |
140 |
2100 |
1.5 |
|
R-404A |
110 |
3260 |
358.600 |
36.6, 48.3 and 14.6 |
|
Other HFC's |
66 |
various |
(60.000) |
various |
|
SF6 |
13 |
23900 |
310.700 |
3200 |
|
PFC (C3F8) |
8 |
7000 |
56.000 |
2600 |
|
Total |
912 |
|
1.697.400 |
|
(44%, 52%, 4%)
GWP (Global Warming Potential) for HFC-143a is 3800 and GWP for HFC-125 is 2800.
In comparison the definition of GWP = 1 for CO2
Figures showing the amount of consumption appear from a survey performed by the Danish EPA on ozone layer depleting substances and potent greenhouse gases (the Danish EPA, 1998). This report has been prepared by Jan Holmegaard Hansen and Tomas Sander Poulsen, COWI.
It appears that if the entire amount of these substances is released to the atmosphere, it will cause an increased emission of greenhouse gases, corresponding to app. 1.69 million tonnes, which is nearly 3% of the Danish CO2 emission (57.3 million tonnes in 1997, corrected for electricity export). It should be emphasised that the figure represents the consumption of raw materials and for that reason the potential emission of these substances. The actual emission will depend on the extent of recollection and successful destruction of the substances.
A substantial increase in the consumption of HFC substances has been registered. In some cases these substances are used as substitutes for CFCs and HCFCs. However, consumption in 1997 is at the same level as in 1996. In 1997, 1225 tonnes of HCFC were used in Danish industry and it can be expected that part of the consumption will be converted into HFC substances when the use of HCFC becomes prohibited in the year 2000/2002.
From an environmental point of view the use of HFC substances instead of CFCs and HCFCs is an improvement, because the impact on the ozone layer is eliminated. CFCs and HCFCs are also very strong greenhouse gases, but a certain amount of disagreement currently prevails about how the substances exactly contribute to the greenhouse effect.
The substances contribute with two contradicting effects: On the one hand they are very strong greenhouse gases with GWP values of 4000 (CFC-11), 8500 (CFC-12) and 1700 (HCFC-22). On the other hand, the substances contribute to the decomposition of stratospheric ozone, which also is a green house gas.
In addition, it should be mentioned that the contribution to the greenhouse effect for different HFC substances covers a wide field. For instance GWP values range from 140 (HFC-152a) to 11700 (HFC-23).
A substantial increase in the consumption of PFC substances is also expected because of an intensive sales campaign for a drop-in substitute for CFC-12 in refrigeration systems. This drop-in refrigerant contains a PFC substance with a high GWP factor and a very long atmospheric life (see chapter 5).
Achievements so far
By means of the now completed CFC programme (initiated by the Danish EPA) and the Cleaner Technology programme, various activities have been supported to encourage development of products and production processes that do not use HFC or other potent greenhouse gases.
In co-operation with industry various developments have been carried out, e.g. refrigerators and pre-insulated district heating pipes using hydrocarbons as blowing agent for insulating foam, apparatus for charging hydrocarbons in refrigerators, application of water and inert gases in fire extinguishers etc.
Natural refrigerants comprise the consumption of substances which already form part of nature's own cycle, i.e. ammonia, hydrocarbons, CO2, water and air. Some of these refrigerants might be chemically produced, e.g. ammonia.
The Cleaner Technology activity that at present is in progress is called "Programme for Natural Refrigerants" and is carried out by DTI Energy in co-operation with a number of industrial companies. Several initiatives have already been put into action: development of methods to produce small ammonia refrigeration systems, a machine for production of ice slurry (a mixture of water, alcohol and ice, applicable as secondary refrigerant) and a preliminary project on cooling containers (reefers). In addition, a major international conference on natural refrigerants was held in Aarhus, Denmark in September 1996, and it received financial support from the Danish EPA.
In addition, the Danish Energy Agency supports the development of new energy saving refrigeration systems using natural refrigerants. The following projects can be mentioned: Development of a refrigerant plant, using water as refrigerant (the "LEGO-plant"), development of commercial refrigerators using hydrocarbons as refrigerants, application of ammonia as refrigerants in supermarkets and an ammonia cooling system as demonstration plant in a big city hotel.
It should be mentioned that the total consumption of CFC substances in the late 1980's amounted to app. 6000 tonnes. Most of the previous applications of CFC have now been replaced by natural substances, i.e. hydrocarbons in aerosol cans, in insulating foam and in certain refrigeration systems, water for cleaning electronic components, ammonia in certain refrigeration systems, etc.
2 Aim of project and organisation
As far as the potent greenhouse gases HFCs, PFCs and SF6 are concerned, the aim of the project is to describe the following conditions within each field of application:
 | Application and consumption figures (from survey prepared by the Danish EPA) |
| Emission to surrounding environment / accumulation in products |
| Alternative technology, development steps and possible implementation in Denmark or abroad |
| Estimated costs by introduction of alternative technology and other obstacles for such introduction (machinery availability, energy consumption, safety rules, standards etc.) |
| Demand for a possible Cleaner Technology activity and description of such project |
Information is collected by means of contacting relevant
industrial enterprises, trade organisations in Denmark and
abroad and green organisations. Supplementary information
will be collected by means of attending technical
conferences, amongst others within the field of
refrigeration technology and PU-foam.
Such measurements will allow the environmental authorities
and Danish industry to achieve a sound background for
further estimation of the practical possibilities within
technology, economy and safety for phasing-out potent
greenhouse gases within different fields of application.
At the same time, a broad perspective of the areas requiring
Cleaner Technology effort in order to develop new, more
environmentally friendly technologies will be obtained.
If introduction of alternative technologies will create a
considerable change of the energy consumption, this will be
specifically mentioned. Obviously, this is a very important
factor. Possible increase of energy consumption very soon
means reduction of the environmental advantages which have
been achieved by phasing-out potent greenhouse gases within
different fields of application. On the other hand energy
savings might encourage further introduction of new
technology.
The project is carried out by DTI Energy but has a steering
committee appointed by the Danish EPA and comprises the
following members:
Lise Emmy Jensen, Danish EPA (chairman of the first part of
the project)
Frank Jensen, Danish EPA (chairman of the second part of the
project)
Per Henrik Pedersen, DTI Energy (responsible for the
project)
Michael Wedel Sørrensen, Confederation of Danish
Industries
Morten Arnvig, AKB (Authorised Refrigeration Installers
Association)
Tarjei Haaland, Greenpeace Denmark
Dorte Maimann, Danish Energy Agency
Lars Frederiksen, Danish Energy Agency
As mentioned in the aim of project, this will be performed
in close co-operation with the Danish EPA and Danish
industry.
A status report was written in the autumn of 1997. It was
published in Danish and English (Working Report No. 101 and
102, 1997) and was also placed on the Internet via the
Danish Ministry of Environment and Energy. This report is a
revised and extended edition of the status report from 1997;
data and knowledge about technology development have been
updated. Specific suggestions to the Cleaner Technology
projects have also been incorporated.
Organisation of work
The Danish EPA published three reports in English on
alternative technologies in 1995. Thus, a comprehensive
account on the state-of-the-art, as it appeared in 1995, is
available within the refrigeration area, poly-urethane foam
and substitution of halon for fire extinguishing.
This report is divided into different categories according
to types of substances. Chapter 3 describes the consumption
of HFC substances and their substitutes, chapter 4 refers to
the consumption of PFC substances and chapter 5 deals with
the consumption of SF6 and its possible alternatives.
During the project, DTI Energy has been in contact with a
number of Danish enterprises and technological institutes to
obtain knowledge. That is reflected in the descriptions of
the individual areas of application and replacement
possibilities.
The status report was prepared according to the comments
from the steering committee and the steering committee's
member's support bases, including the CFC group under the
Confederation of Danish Industries. The comments were sent
to DTI Energy and relevant factual comments were then
included.
In addition, DTI Energy has received comments from the
following persons: Jan Holmegaard Hansen, COWI, Erik Lyck,
DMU (National Environmental Research Institute), Ole John
Nielsen, Risø National Laboratory, Rolf
Segerstrøm, Electrolux, Stockholm and Alexander
Pachai, AirCon A/S.
Lists of references on ammonia refrigeration systems,
installed by Sabroe Refrigeration and Gram Refrigeration
during recent years in Denmark, have also been received.
DTI Energy would like to thank everybody who has contributed
to this report with comments and suggestions.
In the final report all fields of application have been
revised with regard to new information which e.g. has been
obtained via renewed contact with relevant companies and
from knowledge obtained about substitution possibilities
from abroad.
Parallel with this report, DTI Energy has prepared a
corresponding report for the Nordic Council of Ministers. It
deals with more or less the same topics as the Danish
report. However, some topics have been dealt with in greater
detail such as e.g. consumption of SF6 in the production of
magnesium, consumption of SF6 in connection with the
production of power switches and emission of PFC substances
in connection with aluminium production. These industrial
fields are typical for other
On the other hand, the Danish report is more detailed about
specifically Danish topics, e.g. production of
refrigerators, cooling containers, district heating pipes,
jointing foam and noise insulating windows.
Appendix B in this report has been prepared in co-operation
with the Nordic project and will also form part of the
Nordic report.
As it was possible to gain access to the status report on
the Internet we have received inquiries from a number of
foreign researchers. In particular, we would like to mention
correspondence with Mr. Jochen Harnich from Massachusetts
Institute of Technology who we have exchanged information
with, in particular concerning consumption and emission of
PFC substances and SF6.
3 Application of HFC substances and possible alternatives
HFC (HydroFluoroCarbons) is the name for various
substances, which have been produced by placing a number of
fluoride atoms on hydrocarbons. However, some hydrogen atoms
will be left in the molecule. The most common HFC substances
are:
|
Substance |
Chemical |
Boiling |
GWP |
Atmospheric |
|
HFC-23 |
CHF3 |
-82.1 |
11700 |
264 |
|
HFC-32 |
CH2F2 |
-51.7 |
650 |
5.6 |
|
HFC-125 |
C2HF5 |
-48.4 |
2800 |
32.6 |
|
HFC-134a |
CH2FCF3 |
-26.5 |
1300 |
14.6 |
|
HFC-143a |
CF3CH3 |
-47.5 |
3800 |
48.3 |
|
HFC-152a |
C2H4F2 |
-24.2 |
140 |
1.5 |
|
HFC-227ea |
C3HF7 |
-17.3 |
2900 |
36.5 |
The HFC substances are used in Denmark mainly as refrigerants in refrigerators and as blowing agent of polyurethane foam. The HFC substances are also used for a number of minor purposes, for instance as propellant agent in special aerosol cans. Abroad, HFCs are used for special fire extinguishing purposes.
This chapter is divided in sections according to main consumption areas. In section 3.1 the refrigeration industry is discussed and the chapter is further divided, e.g. for domestic refrigerators and freezers, commercial refrigerators etc.
3.1 Refrigeration industry
The refrigeration industry in Denmark is of significant
importance and includes companies such as Danfoss, Sabroe,
Gram, Vestfrost, Caravell, Elcold and Gramkow.
About 15,000 people are employed within the refrigeration
industry, which has an annual turnover of more than 15
billion DKK. Thus, it is an industry of major importance to
Danish economy and employment.
The refrigeration industry produces a large number of
products covering a wide spectrum. From mass-produced
refrigerators and freezers to industrial refrigeration
plants, produced by Sabroe Refrigeration, one of the worlds
leading manufacturers of such. In addition, various
components for refrigeration plants produced by Danfoss, one
of the worlds leading manufacturer of refrigeration
components. Also minor refrigeration companies, assembling
commercial refrigeration systems in supermarkets, could be
mentioned.
This chapter is divided according to main products.
Paragraph 3.1.1 describes domestic refrigerators and
freezers. In this chapter both the consumption of HFC, used
as refrigerant in refrigerators and the consumption of HFC
as blowing agent of insulating foam in the cabinets are
mentioned, as these areas of consumption are closely
related.
3.1.1 Domestic refrigerators and freezers
There are 6 Danish manufacturers of refrigerators and
freezers, i.e. the companies of Vestfrost, Gram, Caravell,
Derby, Frigor and Elcold. Annually, these companies produce
app. 1.5 million units and most of them are exported. App. 1
million units are household refrigerators and almost half a
million units are commercial refrigerators.
The annual sales in Denmark of domestic refrigerators and
freezers has for years ranged between 250,000 and 300,000
units, among which a significant number of refrigerators are
imported from Germany, Italy and Sweden in particular.
An estimated 5.000 people are employed within the production
of refrigerators, freezers and components. Obviously, this
industry is very important to Danish economy and
employment.
Until 1993, domestic refrigerators and freezers were
produced with CFC substances in the cooling circuit and in
the insulation foam. App. 100 - 200 gram of CFC-12 was used
in the cooling circuit and app. 500 gram of CFC-11 was used
in the insulation foam.
In the following years the refrigeration industry went
through a rather turbulent period due to a number of
technologies being introduced as substitutes for CFC. At
first, HCFC substitutes were used in replacement of CFC-11
in the insulating foam.
Danfoss developed compressors that could use HFC-134a as
refrigerant.
These technologies were introduced by Danish and foreign
manufacturers of refrigerators in replacement of the CFC
technology. From an environmental point of view the
advantage was significant. The Danish manufacturers of
refrigerators were some of the first deliverers of non-CFC
refrigerators, which made them competitive on the European
markets where restrictions on CFCs in refrigerators had been
introduced. As a result of this, the production at Vestfrost
in 1994 was more than 700,000 units.
After that time, demands also appeared to the phasing-out of
HCFC substances. Some companies introduced HFC-134a as
blowing agent of the insulating foam. This was additional
environmental progress compared to previous methods, as the
refrigerators were now completely nondependent on any form
of ozone depleting substances.
The environmental organisations started to question the
environmental impact of the HFC substances. Certainly, the
HFCs are not depleting the
ozone layer, however they are potent greenhouse substances
which will contribute to an increased greenhouse effect when
released in the atmosphere. Thus, finding alternatives to
the HFCs would be advantageous.
It should be mentioned that the CFC and the HCFC substances
are potent greenhouse gases as well.
In 1992, Greenpeace Germany joined forces with the previous
East German producer of refrigerators, FORON, and produced a
refrigerator (called "Greenfreeze") operating on a
refrigerant mixture of propane and butane. The mixture had
pressure and temperature conditions, corresponding to
CFC-12, and the system was provided with a CFC-12
compressor. The entire system worked satisfactorily. By
these means Greenpeace contributed effectively in breaking
down a psychological barrier against the use of a flammable
refrigerant.
Danfoss started up development of compressors running on the
hydrocarbon isobutane, and German manufacturers of
refrigerators, among others Bosch/Siemens, started to use
these compressors. Shortly after, 35 types of refrigerators
using isobutane as refrigerant were introduced by
Electrolux. Thus, a comprehensive selection of refrigerators
using isobutane as refrigerant was available.
At the same time it was discovered that the hydrocarbon
cyclopentane could be used advantageously as blowing agent
for polyurethane foam in refrigerators. This discovery was
used in some German refrigerators and in many Electrolux
factories. Both isobutane and cyclopentane have a very small
direct impact on the greenhouse effect compared with the HFC
substances. The GWP value of these hydrocarbons is app. 3,
whereas HFC-134a accounts for a GWP value of 1300 (time
frame = 100 years, GWP for CO2 = 1).
After this an avalanche started to slide, which in a few
months forced the German refrigeration industry to convert
to hydrocarbons. Also foreign manufacturers, who wanted to
sell refrigerators in Germany, were forced to deliver
refrigerators with hydrocarbon technology. This step was
necessary, if they wanted to contribute to the selection of
goods in warehouses and consumers magazines. More than 95%
of the new refrigerators on the German market use
hydrocarbons in the cooling system and as blowing agent for
the insulating foam.
However, many people feared that an explosion accident might
happen in some of the refrigerators due to the explosive
mixture of hydrocarbons and air, which might appear in the
cabinet. The danger that a spark from thermostat, door
contact or lamp might ignite such explosive mixtures was
imagined and debated.
This problem was solved by placing various potential
spark-generating components outside the cabinet and to take
preventive measures against any refrigerant leakage inside
the cabinet.
At present, more than 20 million years of operation have
been registered in Germany. According to available sources
of information no accident has been registered so far.
Some people believe that the safety condition of the
refrigerators has improved. Still, some people store lighter
gas (for lighter refilling) in refrigerators. Unfortunately,
this has caused explosion accidents in some old
refrigerators where gas leaking from the gas dispenser was
ignited by the thermostat or by the door contact.
In addition, people were worried about the perspectives of
increased electricity consumption after the new types of
refrigerators had been introduced. This might have increased
the contribution to the greenhouse effect caused by an
increased CO2 emission from fossil fuels utilized at power
plants. Also this anxiety proved non-relevant. The energy
efficiency of the new hydrocarbon-based refrigerators is at
least as good as the efficiency of the old system based on
HFC substances.
Refrigerators using isobutane as refrigerant are less noisy
than refrigerators using HFC-134a, among others because of
reduced pressure conditions in the compressor.
Another problem with HFC-134a is that it requires synthetic
ester oil. It is very absorbent and it can be a problem that
the oil sucks water from the air.
In Denmark the company Vestfrost quickly introduced
hydrocarbon technology in the insulation foam and that i.a.
took place with support from the Danish EPA.
In 1993-94, the Danish company A' Gramkow in
Sørnderborg developed a hydrocarbon charging station
also supported by the Danish EPA. The company is now among
the largest manufacturers of hydrocarbon refrigerant
charging equipment for refrigerators in the world.
Danfoss is one of the worlds leading manufacturers of
hydrocarbon compressors for refrigerators and freezers. App.
half of the production, which takes place in Flensburg,
Germany, is laid out for isobutane application.
Hydrocarbon technology is making progress in Europe and
certain developing countries, including Argentina and China.
To achieve EU's environmental label it became a demand in
1996 that refrigerators should not contain potent greenhouse
gases in the refrigerant or the insulating foam. This means
in practice that hydrocarbons are necessary to obtain the
label.
In 1998, Vestfrost was awarded the EU environmental label
for a combined refrigerator/freezer and as far as we know it
is the first refrigerator that has received the EU
environmental label.
As far as we know, Vestfrost is the only Danish manufacturer
who has converted to cyclopentane in the insulating foam.
However, several other manufacturers have invested in
equipment enabling the application of cyclopentane. For some
of the other companies this means investments in factory
rebuilding due to compulsory precautions against fire.
DTI Energy knows of another Danish manufacturer who has
partly converted to cyclopentane.
The smaller Danish manufacturers use HFC as blowing agent
for insulating foam. HFC is used because it still is less
expensive than cyclopentane as it requires an increased
amount of plastic when used. However, this aspect is being
levelled by new plastics definitions.
|
Tonnes |
HCFC-22 |
HCFC-141b |
HCFC- |
HFC- |
HFC- |
R-404A |
|
Insulating foam |
0 |
0 |
7 |
264 |
0 |
|
|
Refrigerant |
|
|
|
298 |
|
8 |
Vestfrost is the only Danish manufacturer who can charge isobutane on all production lines.
In September 1996, Greenpeace Denmark carried out a survey on hydrocarbon refrigerators and discovered that there are more than 108 designs in the Danish market. Several refrigerators are imported from Germany, Sweden, Slovenia and Italy. Greenpeace is currently busy carrying out a new survey and the temporary results show that the number of hydrocarbon refrigerators has increased to app. 271. That corresponds to app. 41% of all models in the market.
It is DTI Energy's impression that all Danish manufacturers realise that certain restrictions will be introduced in Europe as the Kyoto protocol has included HFC substances on the list of greenhouse gases that have to be reduced. The restrictions will comprise the future use of HFC substances and also that "it might become necessary to change to hydrocarbons". However, Danish manufacturers still want to produce units with HFC substances for countries demanding these and in particular for the USA, where distribution of refrigerators charged with a flammable refrigerant is not possible for the time being.
Non-HFC technology is available. In Denmark it is purely economic considerations that restrict the introduction of their use. These economic barriers mainly consist of investments in factory buildings, as rebuilding often will be necessary to secure fire-protecting areas in connection with the foaming process and charge of refrigerant. Furthermore, the investment in a hydrocarbon charging system and training of personnel will be necessary. Finally, approval of products together with accomplishment of laboratory tests for energy consumption measurements must be carried out.
It should be mentioned that new technology is being introduced in compressors. Danfoss has developed a compressor range for domestic refrigerators. These operate on isobutane and have variable speeds, which generate considerable energy savings of 30 to 40%.
The energy savings are not achieved because of the refrigerant, but rather because of the possibility of optimising control of the device. The new compressors are included in the Danfoss product range and a sales increase is expected for the next years. The price is currently somewhat higher than the price of traditional compressors.
At DTU (the Technical University of Denmark) and Aalborg University tests on a similar compressor for refrigerators have been carried out together with Danfoss and Gram. Isobutane was used as test refrigerant and also in this case energy savings of 30 - 40% were measured. In this case it was decisive to use isobutane as refrigerant, as application of HFC-134a would create a too large cooling capacity. This compressor has not yet been put into production.
Additionally, it should be mentioned that at present no hydrocarbon compressors applicable for direct current (12 V or 24 V) exist. HFC-134a is used as refrigerant in small refrigerators and freezers for trucks, yachts and other applications without main voltage. Development of direct current compressors for isobutane should be possible, but an investment from the compressor producer is necessary, which demands a market potential for these compressors.
A number of serum coolers for application in e.g. India are produced in Denmark. Sales of these coolers are co-ordinated by WHO and UNICEF, who demand the use of HFC-134a as refrigerant. A considerable number of direct current compressors are used in these coolers, which are often run by solar cells (photovoltaric).
3.1.2 Commercial refrigerators and freezers
The same companies which produce domestic refrigerators
and freezers (Vestfrost, Gram, Caravell, Derby, Frigor and
Elcold) account for a considerable production of commercial
refrigerators and freezers. In particular, ice cream
freezers and can coolers for retail shops are in question,
but to a small extent refrigerators for hotels, restaurants,
bakeries etc.
The production method of bottle coolers and ice cream
freezers is almost the same as for domestic refrigerators.
The insulating foam is produced in the same way as mentioned
above. Vestfrost uses cyclopentan and the other parts use
HFC.
Until now, no compressors for isobutane for commercial
refrigerators have been available in the appropriate
size.
In co-operation with Vestfrost, Caravell and DTI Energy,
Danfoss is developing a new compressor concept for isobutane
as refrigerant and with variable speed. These compressors
are adjustable to most commercial refrigeration units.
The first experiences show that the compressors function
satisfactorily. This project is subsidised by means of the
CO2 scheme under the Danish Energy Agency. 40 can coolers
and 50 ice-cream freezers will be produced for testing in
retail shops. In addition, a number of prototypes will be
tested.
It should be mentioned that in Great Britain several units,
using hydrocarbons as refrigerant, have been produced.
Compressors for CFC-12 or HFC-134 have been used, in
addition with a hydrocarbon mixture of propane/butane,
having the same pressure/temperature conditions. Among
others, Elstar has produced wine and beer coolers with
hydrocarbons as refrigerant. This company has erected
thousands of such coolers and solely uses hydrocarbons as
refrigerant.
According to present standard specification the amount of
flammable refrigerants is limited to 150 g. It is estimated
that most commercial refrigerators and freezers will have a
refrigerant charge smaller than this.
3.1.3 Commercial refrigeration systems
Commercial refrigeration systems are systems that e.g.
are used for cooling purposes in supermarkets, speciality
shops, hotels and restaurants and computer rooms. They can
also be smaller refrigeration systems for industry.
Typical commercial refrigeration systems are for instance
used in supermarkets, where direct cooling has been used so
far. The cooling compressors are placed in a machine room
separated from the place of cooling.
Refrigerant is transmitted in long tubes into the retail
shop, where evaporation takes place in the heat exchangers
of refrigerators and freezers inside the shop. The
refrigeration gas is sucked back to the compressors.
This principle occurs in numerous variations and sizes, from
small bakery shops or butcher shops to computer offices,
from hotels and restaurants to very large warehouses with
more than 50 refrigeration systems.
In section 3.1.7 air conditioning systems are described,
however it should be mentioned that there is no distinct
difference between commercial refrigeration systems and air
conditioning systems. Systems with several refrigeration
locations, including air conditioning, are often seen.
Previously, CFC or HCFC based refrigerants like R-502,
HCFC-22 and CFC-12 were used. In recent years many systems
have been changed to HFC based refrigerants like HFC-134a or
R-404a. New systems, built in recent years, are charged with
HFC refrigerants as well.
In Denmark and abroad some new systems have been built
recently. See more information later in this section.
|
HCFC-22 |
R-404a |
Other HFCs |
|
600 |
102 |
66 |
In addition, 54 tonnes of HFC-134a is used as 'refrigerant (other areas)'. The 66 tonnes of 'Other HFCs' are 26 tonnes R-401A, 14 tonnes R-407C, 10 tonnes R-402A and 16 tonnes other HFCs.
The commercial refrigeration area is the most heterogeneous one within the refrigeration industry. A large number of enterprises are involved in selling and installing refrigeration systems. The refrigeration systems are composed of standard components provided for the purpose. Tubing is often quite extensive, earlier resulting in a significant rate of leakage per year, i.e. 20 -25% of the refrigerant charge.
AKB (Authorized Refrigeration Installers Association) has contributed considerably to quality improvement by securing that the systems remain tight. Nobody knows the exact leakage rate but AKB has prepared a policy about reducing the rate. However, there are limits to how tight the systems can become and that is especially the case for direct cooling in i.a. supermarkets.
On the other hand, if indirect cooling is applied, then refrigerant filling and leakage rates can be reduced drastically.
There are many commercial refrigeration systems and therefore their commercial value is considerable. Still many old systems are operating on CFC refrigerants because a change to HFC based refrigerant would be a cost out of proportion with their age. Mainly, the newer refrigeration systems have been changed to HFC refrigerants.
It has been attempted to convert one particular system to propane, however the conclusion was that changing a CFC/HCFC or HFC system to propane is not realistic, as the required information for approval by the National Inspection of Labour in Denmark is seldom easily obtained.
Thus, it would be reasonable to continue operation with the existing systems but take appropriate precautions for leak proofness. When ready for scrapping, recovery of refrigerant is necessary for further treatment at the KMO (Danish refrigeration industry's recovery and recycling scheme) for purification and reclamation or sending to destruction.
KMO is a voluntary arrangement within the refrigeration trade and has been supported by the Danish EPA.
Natural refrigerants are substances that are already included in nature's own cycle, for instance ammonia, hydrocarbons, CO2, water and air.
Systems for natural refrigerants to be used in supermarkets have been built in Denmark and abroad. Either ammonia or hydrocarbons are used as refrigerant. As these are not permitted in the shop itself, indirect cooling must be used, i.e. a secondary refrigerant (brine).
For many years, secondary refrigerants have been used in certain refrigeration systems, among others in water/glycol mixtures or water/saline mixtures. Recently, it has been mentioned that ice slurry or CO2 under high pressure could be used. Systems with indirect cooling are more expensive that systems with direct cooling as investments have to be made in an extra pump and a heat exchanger. In return, there will be less refrigerant leakage down to app. 5% per year. Refrigerant charge is also much smaller than for corresponding direct systems.
In Sweden, there are demands for using indirect cooling. According to Svensk Kylnorm indirect cooling has to be applied if the refrigerant charge in the primary refrigerant system exceeds 30 kg. If the charged amount is between 10 and 30 kg the system has to be partly indirect which in practice means that the refrigeration of cold stores will be indirect while the refrigeration of freezers will be direct.
The Danish Energy Agency and the Danish EPA have financially supported the construction of a new refrigeration system at Schou-Epa (now called Kvickly), which is the biggest supermarket in Roskilde near Copenhagen. An ammonia refrigeration plant is used, placed in a container on the roof of the building. A water/saline mixture is cooled in the ammonia refrigeration system, which is then pumped into the shop at two temperature levels to allow cooling or freezing.
The project is carried out by Sabroe + Sarby in co-operation with DTI Energy. The system replaces more than 30 old CFC or HCFC-based refrigeration systems and energy savings amount to app. 35%.
However, energy savings in relation to a new, parallel coupled HFC refrigeration system would be insignificant and perhaps it would have a somewhat greater energy consumption.
Refrigeration systems, using ice slurry (a pumpable mixture of water, alcohol and ice, resembling thin sorbet ice) have been tested abroad. Ice slurry is a secondary refrigerant, which advantageously can be used for refrigeration purposes of up to 0/C.
Some of these plants exist in Germany, Norway and England. However, this technology does not seem to be fully developed, as some teething problems have appeared.
Commercially accessible German and Canadian ice slurry generators are now on the market. The generator functions by means of ice that is generated inside a vertical or horizontal cylinder. Afterwards a mechanical scraper scrapes off the ice. The generators are rather expensive.
DTI Energy has developed a new principle for ice slurry generators without mechanical scrapers. Pumping the ice through a traditional heat exchanger with a special surface coating generates ice slurry. The generator has been developed with financial support from the Danish EPA, and at the moment tests are being carried out at DTI Energy in co-operation with Sabroe Refrigeration.
A new "Ice Slurry Centre" has been founded and various companies are involved in the project including Sabroe, Grundfos, tt-coil, Swep, Texaco, Georg Fischer, Hans Buch, Sunwell and Institute for Applied Chemistry, DTU. DTI Energy is involved in all development activities and carries out secretariat functions and administration of the centre.
The main objective of the centre is to develop and produce components for ice slurry. Knowledge and competence are transferred through the centre to products, thus ensuring functionality of the products and optimum interplay between them. The following products are to be developed: ice slurry generator, equipment for measuring ice concentration, pumps, pipe systems and valves, heat exchangers, storage equipment etc.
The centre is supported by the Danish Agency for Development of Industry and Trade and a user group is also connected, comprising FDB (the Danish Co-operative Union), the Danish Meat Research Institute and the Danish Fishermen's Association.
Ice slurry is expected to become important to future refrigeration systems with indirect cooling in commercial refrigeration systems. Ice slurry will probably also be used for new refrigeration purposes such as direct contact freezing.
Pressurised CO2 can advantageously be used as refrigerant for freezing applications. Laboratory tests have been carried out in Denmark and systems exist abroad that use the same principle.
In the Programme for Natural Refrigerants (included in the Cleaner Technology Programme) DTI Energy is currently carrying out 2 subprojects called "Introduction of ammonia in smaller refrigeration systems" and "Information to the Danish refrigeration trade concerning the use of ammonia in smaller refrigeration systems".
The objective of the subprojects is to investigate and clarify problems in connection with the use of ammonia in small and smaller split-plants, to give advice and assign methods for plant design and to ensure that know-how is passed on to the refrigeration trade and realised in practice.
The projects include market research; description of fields of application and types of application; the preparation of safety measures, dimensioning rules, service and maintenance procedures; problem analyses regarding plant components, pipes and assembling methods; the development of laboratory equipment and tests with the same; construction and measurements carried out on demonstration plants, and reporting and participation in one-day conferences and seminars. The projects also include the formulation of a course programme and the preparation of information and instruction material.
The experimental work connected with the laboratory has become more extensive than planned. So far it has revealed that the problems against expectation not only have to do with the materials and assembly methods of the pipe system, but also in making the components operate satisfactorily with regard to refrigeration technology and acceptably with regard to energy consumption.
DTI Energy has carried out a demonstration project that was financially supported by the Danish Energy Agency. The objective of the project was to develop and demonstrate an ammonia based refrigeration plant for milk cooling at farms with reduced energy consumption and environmental impact.
In February 1998, the cooling system was put into operation at an ecological farm and it has functioned satisfactorily for 7 months. The complete installation comprises a system for cooling and storing milk as well as facilities for milk pre-cooling, drinking water heating, cooling accumulation and the utilisation of the condenser heat for preheating domestic water. Measurements have shown that the consumption of energy due to a low compressor efficiency was higher than expected, but lower than in connection with previous systems. Using ammonia and ice water as brine means that there will be no halogen-containing refrigerant leak detrimental to the environment. The plan is to change to an improved compressor. That will reduce energy consumption further.
Experience has been gained from the project that gives rise to believe that the concept can be developed to a competitive product programme. The project should be followed by new activities ensuring that the experience gained combined with innovation and new experiences from abroad are utilised for product development of future milk cooling systems in agriculture with environmental refrigerants and low energy consumption.
Various projects are being planned including a project about solely using natural refrigerants at a large city hotel.
In the course of the past couple of years, app. 75 new cold storage plants using hydrocarbons as refrigerants have been built in Sweden. They are based on a concept developed by Bonus Energi AB. An example is a new supermarket with a cooling system utilising hydrocarbons. The cooling capacity is 240 kW (for cooling) and 140 kW (for freezing). 7 semi-hermetic compressors are used. The refrigerants are a mixture of propane and ethane (Care 50") and the charge is 35 kg. As secondary refrigerants propylene glycol (for cooling) and CO2 (for freezing) are used. Bonus Energi AB was taken over by Sabroe A/S and the concept is now being marketed throughout Scandinavia, in Germany and the UK. Appendix E contains a reference list of the hydrocarbon cooling plants that have been erected by Bonus Energi AB. Linde AG in Germany has a similar concept.
It is now possible to purchase compressors for propane or propene. Bitzer compressors are used in the Bonus plants. In addition, AirCon A/S sells corresponding compressors from Dorin.
So far, no larger commercial cooling systems with hydrocarbons as refrigerants have been installed in Denmark, although several project reports have concluded that according to current Danish legislation there should be nothing against using hydrocarbons as refrigerant.
One of the reasons might be that in a discussion paper called "Without cooling most things get too hot" published by AKB in 1998, Mr. Flemming Jørgensen from Danfoss A/S warns against using hydrocarbons. FJ i.a. writes: 'Within our trade in general we do not have enough know-ledge or experience and our education and not least supplementary education of the service sector must be supplemented with knowledge, rules, legislation and ordinary common sense when using and handling hydrocarbon-based refrigeration systems'.
Therefore, it is necessary to explain if actual problems exist and if so, what the problems are by means of planning and installation of a medium size commercial cold storage plant with propane.
A demonstration project should include planning, installation and operation of a plant with 100-150 kW cooling output and with propane charge greater than 7 kg. All relevant authorities ought to be involved. A measurement programme should be carried out to determine output, operating conditions and energy consumption. Afterwards instructions concerning how to carry out the programme and who has to be asked and to whom application should be sent etc. should be prepared.
A project should also include development of a basis for qualifying (supplementary) education for refrigeration fitters and service staff.
A project proposal concerning the above has been prepared.
It must be concluded that more experience is required by means of experimental tests with commercial refrigeration systems using indirect cooling. Especially, tests with ice slurry and CO2 as secondary refrigerants are necessary.
It is important that the safety aspects are fully considered and that regulations issued by the Danish National Labour Inspection are fully observed. In that connection it is important that light is thrown on the regulations needed.
The energy efficiency of new refrigeration systems is of great importance, and the energy consumption must not exceed the consumption of new HFC refrigeration systems.
It is important that the costs of refrigeration systems using brine systems (secondary refrigeration systems) are reduced to facilitate a wider use in the future.
It should be mentioned that the application of free cooling i.e. from outside air or harbour waters also is a possibility. Such measures might reduce energy consumption for refrigeration systems during some months of the year, as outside air e.g. can directly cool a room or harbour water can directly cool process water.
Evaluation of possibilities for using natural refrigerants within commercial refrigeration:
For future refrigeration plants the following can be stated:
The plants can be designed for ammonia as well as for hydrocarbons according to the safety measures required. In public premises it will normally be possible to use indirect cooling while indirect cooling can be used in many other cases.
| In the future large commercial refrigeration plants can be designed as ammonia or propane refrigeration plants using indirect cooling. Regarding fields of application large supermarkets could be mentioned. |
| To some extent very small commercial refrigeration systems could be systems using hydrocarbons or ammonia with direct expansion. However, it is demanded that certain safety rules and firm procedures are issued/developed. Among others, the safety rules include a maximum amount of charge, e.g. 1.5 kg (for direct expansion). Suggested field of application is small refrigeration stores and refrigeration furniture in delicatessens, etc. Direct cooling can be used in connection with storage rooms with no public access. |
| - The intermediate sized area is where the most important problems exist. Because of economic and safety reasons it might be a problem to build refrigeration systems using indirect cooling. Small everyday stores could be mentioned. As previously described, a number of development projects are presently in progress and they aim at developing new technology to narrow this rather grey zone area. Likewise, direct cooling can be used in connection with storage rooms with no public access. |
3.1.4 Industrial refrigeration plants
Normally, industrial refrigeration plants are very large
systems, which are used for process cooling within the
foodstuff industry or in the chemical/biochemical industry.
In Denmark, traditional ammonia refrigeration plants are
used for such fields of application.
Almost all dairies, slaughterhouses and breweries make use
of ammonia refrigeration plants. Sabroe Refrigeration is the
leading manufacturer of industrial refrigeration plant,
using mainly ammonia as refrigerant. Also Gram Refrigeration
(York International) is known as supplier of industrial
refrigeration systems using ammonia.
However, many industrial refrigeration plants use CFC, HCFC
or HFC refrigerants, and in most cases this might have been
ammonia refrigeration plants as well.
A tendency of using indirect system solutions prevails, for
example in foodstuff industries, aiming to reduce
refrigerant charge and to avoid ammonia outlet in areas of
work etc. Hence, development of plants, using CO2 as
refrigerant, will be required.
With financial support from the Danish Energy Agency, the
company Sabroe Refrigeration and DTI Energy have developed a
refrigeration plant, using solely water as refrigerant in
the compression process. After production, the 2 MW demo
plant was placed at Lego for cooling of casting machines
producing plastic Lego bricks.
The efficiency of the plant is very high, and the energy
consumption is app. 30% lower than for a newly optimised
ammonia refrigeration plant. The plant has been fairly
expensive to produce, and some years may pass before this
technology is completely developed. It is expected that the
Lego project will be followed by other projects involving
the Danish Energy Agency.
3.1.5 Mobile refrigeration systems
Mobile refrigeration systems are refrigeration systems
installed in cars, trains, aircraft, ships or integral
reefer containers
Integral reefer containers
In Denmark the major field of application lies within
integral reefer containers. The company Mærsk Line is
the world leading carrier of refrigeration goods and has
app. 40,000 cooling reefers in traffic on a global
level.
Previously, integral reefer containers were quipped with a
CFC-12 refrigeration system, and many old containers still
use this equipment. Many new containers are changed to
HFC-134a.
Since 1993, all new refrigeration systems have been
installed with HFC-134a refrigeration plants. In Japan
HCFC-22 is used for this purpose and in the USA substances
like R- 404a and HFC-134a are used. Due to hard weather
conditions at sea, the leakage rate of this type of
refrigeration system is rather high.
Previously, CFC-11 was used in the insulating foam, but is
now replaced by HCFC-141b.
Mærsk Container Industri A/S now produces integral
reefer containers in Tinglev, Denmark, and production is
considerable.
Thermo King Container Denmark A/S in Langeskov produces
refrigeration systems to be installed in integral reefer
containers.
Supported by the Danish EPA, DTI Energy in co-operation with
industry has accomplished a survey aiming to examine the
construction of future integral reefer containers.
The use of flammable refrigerants or ammonia for this
purpose is problematic. At the moment, the range of natural
refrigerants is thus limited to cover CO2 and possibly air
as refrigerant.
In the course of the project the development of a prototype,
testing CO2 as refrigerant, was suggested. Besides it is
recommended to try using vacuum-insulation methods.
A Cleaner Technology project seems relevant for this area,
and DTI Energy has in co-operation with industry formulated
a project proposal concerning this matter.
A/C systems in cars
Previously, CFC-12 was used for this purpose, but in recent
years HFC-134a has been used.
As Denmark has neither any car industry nor special hot
climate conditions, no remarkable activities in connection
with automotive air conditioning have been registered.
However, the company A'Gramkow has produced charging
equipment for the car industry. Still, in cars is an
increasing area of application which might become standard
equipment in the future.
In co-operation with important car manufacturers Danfoss has
participated in an EU-project with the aim of developing a
new type of system using CO2 as refrigerant. Danfoss has
developed a new compressor for this purpose.
It should be mentioned that in some countries hydrocarbons
are used in car air conditioning systems. This is for
example the case in Australia, where thousand of cars are
using these refrigeration systems. Apparently, a hydrocarbon
mixture is used together with conventional equipment,
originally designed for CFC-12 or HFC-134a.
The possibility of fire and explosion accident occurrence in
connection with application of hydrocarbons in car air
conditioning systems has been debated. Hydrocarbons could be
a natural choice, as several kg of hydrocarbons in the form
of petrol, diesel oil and propane gas are already present in
the car.
A/C systems in air planes
For many years, a cold air refrigeration system was used for
cooling passenger cabins in ordinary air planes. A simple
joule process is used, where air is compressed and cooled by
exchange with the surroundings. Afterwards, the air expanded
in a turbine, whereby it turns cold. The energy efficiency
of the process is not remarkably high, but it is used in
planes because of the light weight of components.
A/C systems in trains
In Germany a project concerning a cold air refrigeration
system for trains has been carried out. App. 60 units have
been produced for ICE trains.
3.1.6 Heat pumps
The function of heat pumps is similar to that of
refrigeration systems, as heat is tapped from a source (for
instance fresh air, soil, stable air, process water, etc.).
At higher temperatures this is removed to a heat carrier,
for example central heating water.
The following three main types of heat pumps exist in
Denmark: domestic heat pumps, stable heat pumps or
industrial heat pumps.
Domestic heat pumps are used for space heating and for
heating of water for domestic use. In Denmark, heat pumps
are almost solely used in single family houses, but in
Sweden and Norway a number of very large heat pumps are
connected to collective heat supplies.
In Denmark, there are about 12 manufacturers of such heat
pumps, and quite a number of Japanese units are
imported.
Until now artificial refrigerants have been used, however
the Danish producer Lodam has developed heat pumps using
propane as refrigerant. In 1997, Lodam won a competition in
Holland and therefore they have to deliver 400 heat pumps
utilising propane to Dutch customers. This is a
break-through for Danish, environmentally friendly heat pump
technology. Lodam's heat pump technology has been taken over
by the Swedish company called Nibe. They will continue the
production of heat pumps using propane.
Criteria have been accepted for the Nordic environment label
concerning domestic heat pumps. According to these criteria
no considerable greenhouse gases are allowed in the
refrigerant of the heat pumps if they are to obtain the
environmental label.
Like domestic heat pumps stable heat pumps are compact units
utilising surplus heat from livestock. This heat is utilized
for heating the house and/or for preheating of water for
cleaning etc. in the stable. It is generally the same
companies that install domestic heat pumps and stable heat
pumps.
The Danish Energy Agency has financially supported a
demonstration project on stable heat pumps.
Sabroe and Gram produce industrial heat pumps, and among
other substances ammonia is used as refrigerant.
3.1.7 Air-conditioning systems
So far, no small air-conditioning systems for single
family houses have been produced in Denmark, as our climate
does not necessitate them in private houses. However, an
increased marketing of air conditioning systems (often
Japanese) in Denmark has been registered.
Previously, foreign manufacturers have used R-502 and CFC-12
and later HCFC-22 for this purpose and many foreign
manufacturers are changing to HFC-based refrigerants,
including HFC-134a and R-507C.
A foreign manufacturer (DeLonghi) has produced app. 60,000
air conditioning systems using propane as refrigerant.
IMI in the UK has sold plants with Care 50 (mixture of
propane and butane). Models that can be mounted on walls and
under ceilings are in question. The cooling output is
between 2 and 10 kW.
It should be mentioned that a Danish manufacturer of
dehumidifiers, Dantherm, uses HFC refrigerants.
The situation is different for large air conditioning
systems in office buildings, hospitals etc. Here
refrigeration systems (chillers) are installed for
distributing cold water in the building. Air is cooled in
heat exchangers by means of the cold water.
Various refrigeration systems are available for this
purpose, and previously CFC-11 and other chemical
refrigerants have been used. Ammonia is an excellent choice
for this purpose and a system has been built/ installed at
the main post office in Copenhagen. Furthermore, the system
is equipped with a sea water heat exchange to utilise free
cooling by means of cold harbour water for several months of
the year, thus saving energy.
Appendix B includes a reference list of Sabroe's ammonia
refrigeration plants for chillers built in Denmark in the
later years. Since 1990, 114 plants have been installed in
hospitals, in large office buildings, within the process
cooling industry, at Copenhagen Airport, within the
foodstuff industries and at shopping centres.
Appendix C includes a similar reference list from Gram
Refrigeration (York International) of ammonia chillers. 35
plants have been constructed since 1993, and these are
installed in hospitals, in large office building, industries
etc.
Similarly, it is possible to utilise propane in chillers for
air-conditioning. Bonus Energi AB has erected app. 75 plants
in Sweden. Appendix E contains a reference list of the
plants.
Water vapour compression technology can also be used in
connection with A/C. DTI Energy is involved in mechanical
water vapour compression operated by electric energy and is
also involved in thermal water vapour compression utilising
hot waste water to produce cold water for air-conditioning
purposes. That takes place by means of ejector technology,
where water is the working medium and also the refrigerant.
Waste water is derived from decentralised power stations or
industrial processes.
3.1.8 Cryogenic systems
The application of low temperature systems is relatively
small. Refrigeration equipment is produced, which can cool
laboratory tests and other equipment to very low
temperatures.
Heto-Holten produces laboratory equipment, including
equipment for freeze-drying and low temperature freezers
(cryogenic systems) for hospitals etc.
Normally, the equipment consists of a two-step cascade
refrigeration system, where the first step is an R-404a or
an R-403B system. During the first step of the process,
temperatures down to app. -50/C are reached. During the
second step hydrocarbons are used as refrigerants, either
ethane (R-170) to app. -80 to -90/C or ethene (R-1150) to
app. 100 to - 120/C.
Some foreign competitors use HFC-23 at the lowest step.
It should be possible to use propane during the first step.
This would hardly influence the safety aspects, as flammable
refrigerants are used already. However, compressors approved
for propane are required and tests need to be carried out.
There are indications that this is the case. According to
the Danish agent of Dorin compressors they can be used for
propane.
Possibly, other Danish companies produce cryogenic
systems.
3.2 Polyurethane foam
The consumption of HCFC and HFC substances for production
of polyurethane foam in Denmark in 1997 appears from the
following table:
|
|
HCFC-22 |
HCFC-141b |
HCFC-142b |
HFC-134a |
HFC-152a |
|
Insulation in refrigerators |
0 |
0 |
7 |
264 |
0 |
|
District hearing pipes |
0 |
0 |
0 |
0 |
0 |
|
Other insulation material |
0 |
440 |
4 |
0 |
0 |
|
Other rigid foam |
0 |
145 |
6 |
0 |
0 |
|
Jointing foam |
0 |
0 |
0 |
44 |
5 |
|
Flexible polyurethane foam |
0 |
0 |
0 |
40 |
10 |
Consumption is stated in tonnes, and the figures have been taken from Cowi's survey: Ozone depleting substances and certain greenhouse gases 1997, Danish EPA, 1998.
As it appears quite an amount of HCFC is still used for foaming polyurethane foam. Especially HCFC-141b is in question. In the autumn of 1998, (according to trade sources) that lead to a shortage of the substance as several countries (including Denmark) has encountered a HCFC cap which has been laid down in the EU. Therefore, there is a limited amount to be used in the final part of 1998 and there has been a substantial price increase.
3.2.1 Insulating foam
As already mentioned in chapter 3.1.1, some amount of
HCFC and HFC is used for insulation of refrigerators and
freezers, and the available alternatives have already been
described. Hence, this application will not be discussed in
this chapter.
District heating pipes
More than half of the global production of district heating
pipes takes place in Denmark by ABB, I.C. Møller,
Løgstør Rør, Tarco Energy and Dansk
Rørfabrik (Star Pipes).
Previously, the consumption of CFC and HCFC was
considerable. Thus, approximately 820 tonnes of CNC-11 was
used in 1986. Today the insulating foam is blown by means of
hydrocarbons, especially cyclopentane. In addition, some
district heating pipes are produced with CO2.
The Danish EPA has in co-operation with the industry
obtained approval of the above mentioned type of district
heating pipes for future projects by means of World Bank
funding. This has contributed to a form of standardisation
of pentane blown district heating pipes.
Mads Madsen from European District Heating Pipe s
Association informs that Danish enterprises now deliver
approximately 65% of the world production of district
heating pipes. A small amount of this production takes place
at subsidiary companies, e.g. in Poland.
About 1500 people are employed in district heating pipe
factories in Denmark. In addition, some enterprises work
with pipe laying and assembly of entire energy systems, etc.
Enterprises, which are sub-contractors to district heating
pipe enterprises, can also be mentioned. As can be seen, the
importance to Danish economy and employment is
considerable.
Insulating panels
At least two companies (D.C. System Insulation and Prepan,
previously Dansystem) produce sandwich-insulating panels for
cold store houses etc.
Especially HCFC is used for this production, as some panels
are also produced with CO2 to which a small amount of HFC
had been added for export to Sweden, who has banned the use
of HCFC panels. The exact amounts of HCFC are not known at
the moment, but it is expected that a large amount of the
HCFCs in the column other insulation foam will be used for
this purpose.
In 1986, approximately 140 tonnes of CFC-11 were used for
this purpose.
Alternatively, hydrocarbons, including cyclopentane, could
be used. However, a large investment in production equipment
is required. Certain foreign countries produce panels with
hydrocarbons. In Finland e.g. Hurre Group Oy and Makroflex
Oy produce sandwich-insulating panels by means of
hydrocarbons.
Another alternative is to use CO2 (water blown) foam.
Compared to other solutions, the insulation efficiency is
poorer.
It is to be imagined that vacuum insulation is useable for
this purpose in the future. A possibility could be
production of sandwich-panels with rigid polyurethane foam
with open cells. Afterwards, a vacuum pump will help to keep
the pressure down in the insulation material. The foam
itself is produced by blowing with CO2. Major efforts are
required to develop this technology.
The greatest barrier against the introduction of
hydrocarbons is the large investments required for
rebuilding production equipment. Relatively small
manufacturers are involved and relatively large investments
will be required from them.
Integral reefer containers
HCFC substances are used for production of reefer
containers. The consumption of HCFC for this purpose in
unknown, as it is included in the category other insulation
foam in the Environmental Project No. 342. This is a
relatively new production in Denmark.
The production could be changed to hydrocarbons
(cyclopentane). However, some requirements were to be
considered, including safety precautions for using
cyclopentane as blowing agent. Furthermore, it should be
considered that a possible reduction of insulation
properties will change the construction of containers.
Mærsk Container Industri A/S has stated that the
transition to cyclopentane could lead to reduced insulating
properties of up to 10%.
The greatest barrier against introduction of hydrocarbons is
connected to the disadvantages caused by production stop,
uncertainties about quality, security of working environment
and the economical consequences hereof.
Another possibility would be to use vacuum insulation, where
rigid polyethane foam with open cells are used. A project
has been worked out in co-operation with DTI Energy and
industry concerning this matter. Comprehensive changes in
construction and production are required if switching to
this technology, and examinations and tests will be
needed.
Other types of insulation foam
A number of minor manufacturerss of polyurethane foam use
either HCFC or HFC for a number of purposes. It might be too
expensive to invest in hydrocarbon technology, as large
investments in fire protection are necessary.
Alternatively, foam blown by CO2 could be used, however the
insulation conditions would decrease, compared with foam,
blown by HCFC or HFC. In connection with certain
applications the insulation properties are not decisive.
That might be in cases where the construction implies that
considerable heat bridges already exist or it can be in
cases where there are no greater temperature
differences.
In connection with the first item it can be mentioned that
industrial gates with CO2 blown polyurethane foam are
produced at Nassau Doors.
Another example is foaming of insulation material at Norfrig
A/S who produces cooling boxes for lorries and
semi-trailers. According to Mr. Chris Ungermand, Shell Kemi
A/S, water blown foam is used. They have succeeded in
developing a material with the same insulating properties as
when HCFC-141b was previously used. That has happened by
using glass fibre reinforced barriers on the sides. In that
way diffusion of COs out of the foam and diffusion of air
into the foam is avoided.
The company Tectrade A/S has also developed a new type of
CO2 blown foam (often called water blown foam) where a finer
cell structure leads to improved insulating properties.
Many of the smallest manufacturers of insulating foam have
stopped producing the foam themselves. Instead they purchase
"block foam" which is then cut to suit certain purposes.
Often the foam is only a smaller part of a larger complex
machine.
There is one Danish manufacturer of block foam and the
company is called LM Skumplast. The company has replaced
HCFC-141b with hydrocarbons (isopentane) for foaming. The
plant has been designed by Tectrade A/S.
3.2.2 Jointing foam
Baxenden Scandinavia A/S is manufacturer of aerosol cans
with sealing foam and produce many different kinds.
Previously, CFC or HCFC substances were used as propellant
in these cans, but this has now been banned. In 1986 an
amount between 575 and 800 tonnes of CFC and HCFC was used
for this purpose.
Baxenden very soon introduced an alternative can, which used
propane and butane as propellants. This system was
introduced on the Scandinavian market, and since 1987 only
systems operating on hydrocarbons have been used on this
market.
The situation is different for other markets, including
Germany. A maximum of 50 g flammable propellants may be
stored in the cans, i.e. max. 50 g propane + butane.
Thus, it is necessary to supply an amount of HFC-134a (a 700
ml can normally contains 100 to 175 g propellant).
This derives from an agreement, made by European
manufacturers, but with the exception of Scandinavia. In
other parts of the world hydrocarbons are used.
Only cans with pure hydrocarbon propellants are delivered to
countries, used to work with this propellant, and where
safety precautions concerning ventilation etc. are kept.
Accidents with hydrocarbon based cans have occurred. This
has happened in cases, where safety precautions have not
been kept, and where use has taken place in small rooms,
where fire has been ignited by a match or a lighter.
However, this danger also consists for cans using HFC
substances, as this propellant, due to the content of
hydrocarbon and HFC-152a, is flammable as well.
There are 35 manufacturers in the world, and competition is
hard. Thus Baxenden cannot independently decide the
technological trend, but may produce cans with HFC
substances to other countries than Scandinavian.
Cans with pure hydrocarbon propellants are considerable
cheaper than cans with HFC substances. The propellants have
different qualities, thus a price comparison alone amongst
the cans is not possible. The joint foam achieves different
qualities depending on the propellant.
3.2.3 Flexible polyurethane foam
In Denmark there are two large manufacturers of flexible
polyurethane foam, viz. Bdr. Foltmar and K. Balling
Engelsen.
The main part of production is 'water' blown, i.e. a small
quantity of water is added during production. A chemical
reaction between water and isocyanate will produce CO2,
which is the actual blowing agent.
Some of the production has traditionally taken place using
CFC-11 and later with HCFC substances as propellant.
Especially soft and light quality items for the furniture
industry should be mentioned.
In recent years a mixture of HFC-134a and HFC-152a has been
used as propellant for this production.
Only CO2 blown foam is used in the other Nordic countries.
An agreement has been made stating that foam with a density
less than 23 kg/m3 should not be produced. Hence, no
physical blowing agents are required.
Abroad a certain technology has been developed. Liquid CO2
is used for production of flexible polyurethane foam in
these qualities, and some systems have been installed,
amongst others in the USA and in Italy. The most important
barrier against converting to this industry is investment in
new machinery.
At least two manufacturers of the new technology should be
mentioned, e.g. Canon (Italy) and Bayer (Germany).
Danish manufacturers of flexible polyurethane foam inform
that there is also a barrier in connection with quality, as
some quality problems with the new CO2 technology have
appeared.
According to manufacturers of the above blowing technology
equipment the quality of the new foam is satisfactory.
In certain countries (also in the EU) methylene
chloride is used for production of flexible polyurethane
foam. From a labour protection point of view this is not
conceivable for application in Denmark.
3.3 Fire extinguishants
In connection with the global phase-out of Halon, a
number of chemical substitutions have appeared, including
one, which is based on HFC-227 (e.g. Great Lakes FM-200).
These are marketed rather intensively in many countries of
the world, and this has also been tried in Denmark.
However, in Denmark the use of halogenated hydrocarbons for
fire extinguishing is banned. The substances Halon-1301 and
Halon-1211 were excepted from this, but they are now being
phased-out parallel with the CFCs etc.
Danish enterprises have developed impressive alternative
technologies for fire extinguishing. Especially Inergen,
which is developed by Dansk FireEater. It consists of inert
gases, i.e. argon, nitrogen and some CO2. Inergen can be
used for total room flooding systems in computer rooms,
control rooms, power stations, engine rooms, etc.
Ginge-Kerr Danmark A/S has a similar technology called
Argonite, which consists of argon and nitrogen. In addition,
this company has developed a water mist technology.
The technology of using inert gases for fire extinguishing
purposes has become a remarkable success, also on an
international level. Foreign multinational companies, such
as Wormald, is marketing Inergen.
Other alternatives for chemical fire extinguishing have been
developed, such as the use of CO2 or foam for fire
extinguishing purposes in engine rooms on ships or cargo
vessels, improved detectors combined with manually operated
fire extinguishing etc. However, giving full details on this
topic is beyond the scope of this report.
This entire area has been described in detail in a report
published the Danish EPA in 1995: Environmental Report No.
312: Going towards Natural Fire Exhinguishants, Experience
from Danish Industry.
3.4 Propellant in aerosol cans and foghorns
The Aerosol Statutory Order, published by the Danish EPA,
bans all application of HFC substances for use in aerosol
cans.
The ban does not apply for medical aerosol cans or foghorns,
as medical products are excluded as an exception and the
publication does not regulate the contents in aerosol cans,
where only gas is emitted from the can. However, a revision
to include foghorns has been announced by the Danish
Minister of Environment and Energy
Medical sprays
CFC-11 and CFC12 are still used as propellant in medical
sprays, and especially in astma sprays. At the end of the
1980s the consumption of these products amounted to app. 29
tonnes of CFCs. The products are not manufactured in
Denmark.
Alternative products have been available for many years, for
instance self-inhalated astma powder. However, not all astma
patients are able to inhalate themselves.
Astma sprays with HFC substances as propellant have been
developed.
Foghorns
Foghorns with HFC-134a as propellant can be bought. The horn
is an aerosol can provided with a plastic horn, which is
able to make a loud noise.
Is is estimated that most foghorns are used by the audience
at football matches, however they are also used on sailing
boats as alarm horns to warn other boats.
Greenpeace Denmark has found non-HFC containing alternatives
on the market. These alternatives are available in several
types, where the one type uses isobutane as propellant. The
other type uses compressed air, and re-loading is possible
at petrol stations or by means of a hand pump.
Foghorns operating by means of an electric compressor are
also available. Finally, manually driven alarm horns, which
can be blown up or may be activated by means of a rubber
ball, are available.
3.5 Other fields of application
There is a small consumption of HFC in special cans for
cooling electronic components during repair of electronic
equipment. The flow of liquid HFC cools the component that
the liquid drops come into contact with.
This method enables diagnosis of a defective component. The
consumption is probably modest, app. 0.5 tonnes per year.
According to Naturvårdsverket in Sweden CO2 is used
for this purpose, and equipment is supplied by AGA.
DTI Energy has no knowledge of other fields of application
for HFC substances in Denmark.
However, it should be mentioned that in South East Asia the
so-called Pushn chill beer cans were planned to be marketed.
These cans are chilled by means of direct evaporation of
HFC-134a in the can, whereby the beer is chilled. This
subject has been addressed by the press during the summer of
1997 and European ministers of environment have opposed this
application of HFC substances.
The company behind the self-chilling can has recently
announced that CO2 will be used as refrigerant instead of
HFC-134.
4 Use of PFC substances
PFC means perfluorocarbons, i.e. substances that are
formed with basis in simple hydrocarbons, where all hydrogen
atoms are exchanged with fluoride atoms. These are
substances like CF4, C2F6, C3F8, etc.
As these substances are very stable, they have a very long
atmospheric lifetime. At the same time they are very strong
green house gases. However, only small amounts of these
substances are used in Danish industry, and the main area of
application lies within the refrigeration industry.
Abroad some PFC emission occurs in connection with aluminium
production produced from aluminium oxide (alumina) by means
of an electrolytic process. The PFC substances will only
develop if a special effect, i.e. the anode effect, occurs.
This means a rapid increase of the electric voltage during
which certain PFC substances (CF4 and C2F6) are
produced. In Norway and Sweden considerable efforts in
reducing development and emission of PFC substances have
been made during recent years.
Abroad a considerable amount of the substance C6F14 is used
within the electronic industry.
|
Chemical |
R-number |
Boiling point (C) |
GWP |
Atmospheric |
|
CF4 |
R-14 |
-127.9 |
6500 |
50000 |
|
C2F6 |
R-116 |
-78.2 |
9200 |
10000 |
|
C3F8 |
R-218 |
-36.8 |
7000 |
2600 |
|
C6F14 |
|
+58 |
7400 |
3200 |
4.1 PFC in refrigerant mixtures
According to a survey made by the Danish Environment
Protection Agency app. 8 tonnes of C3F8 (R-218) were used in
1997 as refrigerant in a special mixture.
The refrigerant is used as a drop-in substitute for CFC-12
in refrigeration plants. Consumption has been increased
heavily since 1995 and 1996, with consumption of 1.5 and 3
tonnes respectively.
The refrigerant mixtures are known under various names,
including Isceon 49 (R-413A), which consists of app. 88%
HFC-134a, 9% C3F8 and 3% Isobutane.
New mixtures occur constantly, however the industry is most
cautious about using refrigerant mixtures, as some
uncertainty about the remaining mixture after leakage
prevails. In general, transport of anymore types of
refrigerants than necessary is undesirable.
|
Trade name |
R-number |
Drop-in substitute for |
Composition |
|
Isceon 49 |
R-413A |
CFC-12 |
9% of C3F8, 88% of HFC-134a, 3% isobutane |
|
Isceon 69L (Isceon 69S) |
R-403B R-403A |
R-502 |
39% of C3F8, 56% of HCFC-22, 5% propane |
|
Suva 95 |
R-508B |
R-13, R-503 |
54% of C2F6 and 46% of HFC-23 |
|
Arcton TP5R2 |
R-509A |
|
56% of C3F8 and 44% of HCFC-22 |
|
|
R-412A |
|
5% of C3F8, 70% of HCFC-22, 25% of HCFC-142b |
The mixtures may be conveniently used if extended lifetime of a CFC-based system is required and no recycled CFC refrigerant is available. The only reason for using these mixtures is their capability to extend the lifetime of old CFC based refrigeration systems. This application may be avoided by either converting the CFC refrigeration systems into HFC refrigerant or by maintaining tightness of system until scrapping. It is also possible to refill with used CFC from the KMO Recovery and Recycling Scheme.
4.2 Other applications of PFC substances
DTI Energy has not met other types of application in
Denmark, but apparently small amounts are used in
laboratories.
In Working Report No. 20, the Danish EPA 1996: Consumption
of emissions of 8 fluoride and chloride hydrocarbons (Jan
Holmegaard Hansen, Cowi), the following is mentioned:
One of the importers informs that the company has 2
products containing perflouro combinations on the import
list. Both contain perflourohexane C6F14 as the main
component, however, none of these products have been sold
within the last year. The one product is an inactive liquid
for use in the electronic industry, whilst the other product
(an overactive product) is newly developed and thus never
sold.
It should be mentioned that attempts of selling a PFC
substance as fire extinguishant in replacement for halon has
been carried out abroad. This application of PFC is banned
in Denmark, see section 3.3.
5 Consumption of SF6 and substitution possibilities
SF6 (sulphurhexafluoride) is a heavy gas. According to
the Environmental Project No. 342 (The Danish EPA, 1997) 13
tonnes of SF6 was used by Danish industry in 1997. The
corresponding figures from 1992, 1993, 1994, 1995 and 1996
are 15, 17, 21, 17 and 11 tonnes, respectively.
Glass industry (noise insulated windows) is the far biggest
area of consumption. In second place metal works and power
plants can be mentioned.
Some very small areas of application can be mentioned. DTI
Energy only knows the application of tracer gas and blowing
of car tyres. Apparently, there are some other applications,
for instance laboratory use.
|
Chemical |
R-number |
Boiling point (C) |
GWP |
Atmospheric |
|
SF6 |
R-7146 |
-63,8 |
23900 |
3200 |
The second-largest source of consumption on a global scale is for magnesium production (app. 500 tonnes per year). Other global fields of consumption include degassing of aluminium, cleaning of electronic components and blowing of car tyres.
5.1 Noise-reducing double glazed windows
SF6 (sulphurhexafluoride) is gaseous at normal
temperatures and atmospheric pressures. SF6 is used in some
noise-reduced double glazed windows, where SF6 in an argon
mixture fills the space between the panes of glass. The
purpose is to absorb acoustic waves and thus secure against
noise from the outside.
According to the Danish Environment Protection Agency an
amount of 7.2 tonnes of SF6 was used in 1997 for this
purpose. This examination has mainly been prepared according
to information from suppliers and importers of SF6. The
consumption of SF6 for this purpose is declining, and in
1995 and 1996 the amount used was 13.5 and 9.4 tonnes,
respectively.
Some of the production is sold in Denmark. There are app. 30
producers of this type of noise-insulated double glazed
windows in Denmark.
According to a survey made by the Danish Environment
Protection Agency a direct emission of SF6 occurs during
charging of the windows. This loss varies between 10 and 20%
depending on the equipment and the procedures used.
Previously, the amount of emission was much bigger.
Initially, SF6 is accumulated in the windows, however, when
the windows puncture, the substance will leak out into the
atmosphere.
As no collection or recovery arrangements exist, which would
be difficult whatsoever, the entire amount of SF6 will
probably end up in the atmosphere. As this type of window
has been produced for some years (15-20 years), it is
expected that some emission from old windows with SF6 will
occur in connection with puncture or scrapping of the
windows. If we assume that the lifetime for these windows is
20 years, we are about to reach the point where the actual
emission corresponds with the raw material consumption.
DTI Energy has consulted Peter Vestergaard from DTI Building
Technology and manufacturer representatives. The information
received hereby was that:
| The environmental hazards related to the use of SF6 surprised everybody. They did not think that the end-users (e.g. the city refurbishing corporations) were aware of this matter |
| The consumption of was considered surprisingly high |
| SF6 creates slightly poorer heat insulating properties compared to standard glasses |
| Noise insulated windows are always a combination of other factors like glass in different thickness and possibly laminated |
| SF6 only contributes to a minor degree to noise reduction |
| Cleaner Technology efforts seem relevant in this area, and the environmental effect may be considerable if a positive result of this project is achieved. |
DTI Energy has contacted Delta Acoustics and Vibration
with the purpose of formulating a project within the
area.
A project proposal has been prepared, in which the initial
part of the project (subproject 1) contains a more precise
description of the production of noise-insulated windows,
e.g. type of window, number and application concerning the
extent of traffic noise, expected life time etc. Laboratory
measurements on 8-10 windows with SF6 will be carried out
together with parallel measurements on similar windows not
containing SF6. Thus, the aim of subproject 1 is to
demonstrate the importance of using SF6 as a
noise-insulating medium, where after targets for the
following part of the project (subproject 2) will be decided
upon. Finally, new concepts of windows not containing SF6
will be prepared in co-operation with manufacturers.
5.2 Protective gases in light-metal foundries
According to the Danish EPA the consumption in 1997 of
SF6 used as protective gas for light metal casting, was 0.6
tonnes. The consumption in 1995 and 1996 was 1.5 and 0.4
tonnes.
The production takes place at the company Metallic A/S. Here
SF6 is used in a mixture of other gases (CO2 and atmospheric
air) to protect liquid magnesium from igniting, when casting
the metal for machinery parts. Liquid magnesium is highly
flammable and will ignite when exposed to air.
The same method is used in other countries. A search on the
Internet reveals that a number of different magnesium
casting machines exists, all protected with SF6 systems. SF6
will be released from this source to the environment.
Metallic A/S also casts goods in aluminium, zinc and brass,
but the use of SF6 exclusively takes place when casting
magnesium.
According to Lars Feldager Hansen, Metallic A/S, magnesium
is a very light and strong metal. Consequently, the use of
magnesium parts is increasing in the car industry.
Metallic A/S is currently rebuilding their factory in order
to terminate the use of SF6. Application of SO2 in closed
machinery parts will be introduced instead. Partial
implementation of this technology has already been carried
out and full implementation is expected during the next
year. The new technology has been introduced in co-operation
with Norsk Hydro.
Aluminium production
According to Preben Norgaard Hansen, DISA A/S, SF6 is used
for degassing liquid aluminium before casting. Previously,
chlorine-containing gases were used for this purpose,
however due to the working environment this caused
problems.
SF6 is introduced into the liquid metal in small bubbles
where gas, including hydrogen, diffuses into the bubbles,
which rise to the surface to be released in the
atmosphere.
On a global level app. 20 Disamatic automatic casting
machines for aluminium production exist. This market is
growing steadily, as the use of aluminium for car parts is
increasing.
DISA has previously tested this technology at their test
foundry in Denmark, but is presently not using SF6 for this
purpose. Per Norgaard Hansen is not aware of the use of SF6
for aluminium casting in Denmark.
5.3 Insulating gas in electric power switches
SF6 has a remarkable dielectric value. Because of this, the substance is used as insulating gas in certain high voltage installations. In principle, there are two different fields of application:
| as arc-extinguisher in switches |
| as insulator in compact distribution systems |
According to figures registered by the Danish EPA, the consumption of new SF6 for these purposes was app. 1.4 tonnes in 1995, 1 tonne in 1996 and in 1997 the consumption was app. 4.2 tonnes. Probably, the installed amount is much higher, but the emission is limited because the gas is kept in closed equipment and because the gas is collected and recycled when maintaining or disassembling the equipment. Thus emission only occurs by accident or unexpected leakages.
According to Henrik Weldingh, DEFU (Research Institute of
Danish Electric Utilities), an electric arc will be formed
when switching off the power, and temperatures may reach
extreme values (10,000 - 100,000 K). A substance is needed
for breaking the electric arc by rapid and efficient
cooling, so that power cut off is completed by the time the
current reaches the zero point of the AC sine wave.
Several possibilities prevail, such as:
| The electric arc is blown away by means of highly pressurised air from a vessel. This technology is old and is still used in some systems. A disadvantage is that the release of the compressed air makes a loud noise resembling an explosion |
| Using oil, by which hydrogen is formed. This technology implies a certain risk of explosion and has been abandoned |
| Switching off the current in a closed vessel containing SF6. This method works satisfactorily |
| Switching off the current in a vacuum chamber. This technology also works satisfactorily in the range up to 20 kV. |
No Danish producers of this equipment exist. However,
multinational companies like ABB, Siemens, Group Schneider
etc. produce this type of equipment.
In Denmark about 600 transformer stations in the 10-20 kV
range exist, which are either equipped with SF6 or vacuum
switches. Prices are similar and competition is hard amongst
the producers. Thus non-SF6 circuit switches for the 10-20
kV transformer stations are available. However, space
related problems may arise when changing to this type, and
rebuilding of the entire station may be necessary.
In addition, about 60,000 of 10 kW/400 V sub-stations exist.
In this case the equipment may be based on SF6 both as
switching and insulating agent, but other non-SF6 solutions
are available. Because of the large number of sub-stations,
parameters like reliability, maintenance and small physical
size play a decisive role.
In the high voltage range from 60 kV and up there are no
alternatives.
According to Henrik Weldingh, DEFU, new technology is not in
sight. New semiconductors may be marketed in the future, but
a technological break-through is required, as efficiency is
too low with the known technology.
The other application within the electrical area is as
insulating gas in compact transmission cables. As an example
high voltage cables of 400 kV, from the generator and out of
the power plant, are placed in pipes (for example in 20 m),
filled with SF6. This prevents flashover to the pipe and
thus short-circuiting power cables. Alternatively, the
distance between the cables could be increased, allowing
atmospheric air to become the insulating agent.
As no Danish manufacturers of this type of equipment exist,
the initiation of development projects seems pointless
within this area.
If application of a technology, not containing any strong
green house gases is wanted, installation of non-SF6
switches in the 10 kV system is possible.
5.4 Tracer gas and other laboratory purposes
According to the Danish EPA, the consumption of SF6 by
various research institutes is app. 0.6 tonnes per year.
DMU (the National Environmental Research Institute) uses a
small amount of SF6 as tracer gas for tests of dispersal in
the atmosphere. The purpose of these experiments is to test
mathematical models for dispersal in the atmosphere. This
kind of tests makes among others the foundation for
standards of chimney heights, etc. Only small amounts are
used, varying according to actual projects. According to
Erik Lyck, DMU, an amount of 6 kg was used in 1995, in 1996
no amount was used, and in 1997 less than 100 g was used. In
1998 no application has taken place so far.
The application of SF6 as tracer gas is due to a number of
special qualities of the substance, which makes it hard to
replace. Among others, it is precisely and specifically
detectable in very low concentrations and the concentration
in atmosphere is very low. Foreign tests have been made with
a PFC substance, however this causes environmental problems
as well.
Erik Lyck estimates that there are no useable alternatives,
however the amount used for tests has to be limited and
controlled. The tracing equipment of DMU is that sensitive
that the background level for SF6 is measurable. Erik Lyck
has written an article about this subject.
In Denmark, app. 5 laboratories are performing ventilation
tests. Small amounts of SF6 are used as tracer gas for
indoor tests. The measurements are used for estimation of
pollution dispersal, leakage from heat exchangers and
estimation of short circuit between the airstreams, etc.
Christian Drivsholm, DTI Energy in Taastrup informs that 2
kg per year are used for these tests. Laughing gas (N2O) may
be be used as well, however this is slightly problematic
because of toxicity.
5.5 Car tyres
According to the survey by the Danish EPA no consumption
of SF6 for car tyres is registered. According to various
sources of information large amounts of SF6 are used in
Germany (in the order of 100 tonnes per year) for the
blowing of car tyres. Consequently, DTI Energy has tried to
elucidate this use.
According to conversation with Rudolf Nielsen, DTI Energy,
Torben Skovgaard, The Danish Tyre Safety Council and Jan
Steen Hansen, Continental, the situation is as follows:
A German company named Messer Griesheim (near Hamburg) tried
to sell a system, called Conti Air Safe to Continental,
Denmark. The system was tested in 1990, but has not been
introduced.
The sales argument was that the SF6 molecules, which are
rather big, would be mixed with air in the car tyre, diffuse
into the tire material and prevent/reduce diffusion of air
out of the car tyre.
According to above mentioned persons no SF6 is used for this
purpose in Denmark.
5.6 Other possible applications of SF6
At present DTI Energy has no knowledge of other
applications of SF6 in Danish industry than the above
mentioned.
However, DTI Energy knows that SF6 are used in the soles of
Nike sports shoes. According to a letter from Sarah Severn,
Director for Nike Environmental Action Team to Greenpeace
Denmark (dated September 12, 1997), the consumption of SF6
from April 1, 1996 to March 31, 1997 was 288 tonnes. The
substance is used in Nikes Air models, and the entire
production of these soles is located in the USA.
At the same time Nike announced that a phase-out over three
years of the use of SF6 is initiated and not later than year
2001 SF6 will be replaced with nitrogen.
According to the recent letter of August 17. 1998, from
Sarah Severn Nike, the consumption of SF6 in 1997 was app.
276 tonnes and the consumption in 1998 is estimated to be
app. 164 tonnes. This corresponds with a 40 % reduction.
Nike also states, that the consumers can not clearly
differentiate between shoes produced with SF6 and with
nitrogen.
6 Evaluations and recommendations
A number of activities have been initiated for the
development of HFC substitutes. Many results have been
achieved and satisfactory results are expected of the many
current projects.
As mentioned in chapter 3, a number of projects are going
on, i.e.:
Danish EPA: Programme for Natural Refrigerants:
| Development of small ammonia systems, including new assembling methods |
| Development of ice slurry generator |
| Integral reefer containers with natural refrigerants (preliminary study). This project has been accomplished and a final project proposal has been prepared. |
| The Danish Energy Agency has supported the following projects in progress: |
| Supermarket refrigeration system using ammonia and indirect cooling |
| Water vapour compression system |
| Energy saving commercial refrigerators and freezers using isobutane |
| Cooling with natural refrigerants within the hotel branch |
| Milk cooling system using ammonia for use at a farm. |
The initiation of a Cleaner Technology project on
substitution of SF6 in noise reducing windows is
recommended. This should be carried out in co-operation with
for instance manufacturers.
The initiation of a Cleaner Technology project in
substitution of potent green house gases in integral reefer
containers is recommended. This should be carried out in
close co-operation with relevant industry. The project
should consist of two parts, where the first part is
development and testing of a new cooling system, using CO2
as refrigerant. The second of part is development and
testing of new insulating concepts. One or two containers
should be produced and tested in practice.
Further efforts with commercial refrigeration are
recommended. For instance ammonia or hydrocarbons for direct
or indirect cooling can be used. Construction and testing of
a demo plant has to be carried out. In addition, a parallel
education programme for refrigeration fitters must be
prepared. This project will be made in co-operation with the
relevant authorities.
The establishment of a homepage on the Internet is
recommended in order to allow world-wide distribution of
Danish results. Links to relevant homepages should be
established on this homepage.
Later on projects on other subjects involving potent green
house gases can be initiated, in case of promising
concepts.
Highest priority of projects in areas where Danish
production and know-how already prevail is recommended. By
means of this, an optimum synergistic effect is assured to
secure an efficient development of new products without
green house gases.
7 Project proposals for the Cleaner Technology programme
On the basis of the evaluations and the recommendations in chapter 6 the following lists of proposals for Cleaner Technology projects are made, whilst the proposals are categorised into two priorities:
At short sight the following projects should have highest
priority in the Cleaner Technology programme:
| Development of noise insulating windows without SF6 |
| Integral reefer containers with CO2 refrigeration system and new insulation |
| Commercial cooling systems with hydrocarbons |
| Information on natural refrigerants and other substitutes for HFCs, PFCs and SF6, including creation of a homepage showing the latest results, reports, etc. |
| On a slightly longer sight the following areas should be considered: |
| Insulating panels without HFC or HCFC |
| Flexible polyurethane foam without HFC |
| Blowing of other insulating foam without HFC |
| D.C.-compressor for refrigerators (for isobutane) |
| Low temperature cooling systems with natural refrigerant |
8 Literature
In the report the following literature has been used:
| Environmental Report No. 342: Ozone depleting substances and certain green house gases 1995. Prepared by Jan Holmegaard Hansen, COWI. Danish EPA 1997. |
| Working report No. 98, 1997: Ozone depleting substances and certain green house gases 1996. Prepared by Jan Holmegaard Hansen, COWI. Danish EPA 1997. |
| Ozone depleting substances and certain green house gases 1997. Environmental project to be published in 1998 by the Danish EPA. Prepared by Jan Holmegaard Hansen and Thomas Sander Poulsen, COWI. |
| Working report Nr. 20: Consumption and emission of 8 fluorine and chlorine hydrocarbons. Danish EPA 1996. |
| Svend Auken, Danish Minister for the Environment and Energy, Official Opening of the Conference, Application for Natural Refrigerants, Aarhus, Denmark, 3. 6. September 1996. International Institute of Refrigeration, Paris. |
| List of undesireable substances. Review No. 7, 1998, Danish EPA, 1998. |
| Environmental Project No. 300: Polyurethane Foam without Ozone Depleting Substances; Experience from Danish industry. Danish EPA 1995. |
| Environmental Project No. 301: Going towards Natural Refrigerants; Experience from Danish industry. Danish EPA 1995. |
| Environmental Project No. 312: Going towards Natural Fire extinguishant; Experience from Danish industry. |
| Greenfreeze refrigerator types available on the Danish market, Status March 1998. A user's guide prepared by Greenpeace (under revision). For further information see www.greenpeace.org/~dk. |
| Scandinavian Refrigeration (ScanRef) 4/1997. Article about a Swedish supermarket refrigeration system using hydrocarbons as refrigerant. (In Swedish). |
| Scandinavian Refrigeration (ScanRef) 3/1998. Hvad skal vi med TEWI? Bjørn Grødem. (In Norwegian). |
| Hans Haukås, Reduksjon i forbruket av HFK, tiltak og kostnadar, Rapport 97:32 Statens Forurensningstilsyn. (In Norwegian). |
| Uden køling bliver det meste for varmt. Discussion on the use of refrigerants in retailing, industry and at the end-user. Prepared by AKB (Authorised Refrigeration Installers Association), 1998. (In Danish) |
| Kathryn Ellerton, Allied Signal Inc: Recent Developments and the Outlook for Global Sulphur Hexafluoride, International Magnesium Association Fifty-four, Toronto, June 1997. |
| Letter from Sarah Severn, Director, NIKE Environmental Action Team to Tarjei Haaland, Greenpeace Denmark, dated September 12, 1997. |
| Environmental Report, Norsk Hydro, 1997. |
| Letter from Sarah Severn, Director, NIKE Environmental Action Team to Tarjei Haaland, Greenpeace Denmark. Dated August 17, 1998. |
| Possibilities in reducing consumption and emission of potent green house gases (HFCs, PFCs and SF6). Project for the Nordic Council of Ministers. Preliminary report dated October 1998. |
| Various brochures from Danish and foreign enterprises. |
Appendix A: List over refrigerants and refrigerant mixtures
In the below table the most common refrigerants,
consisting of single substances, are stated:
|
Substance |
R-number |
Chemical formula |
ODP-value |
GWP-value (100 yrs) |
|
Halon-1301 |
R-13B1 |
CBrF3 |
10 |
5.600 |
|
CFC-11 |
R-11 |
CFCl3 |
1.0 |
4.000 |
|
CFC-12 |
R-12 |
CF2Cl2 |
1.0 |
8.500 |
|
CFC-115 |
R-115 |
CClF2CF3 |
0.6 |
9.300 |
|
HCFC-22 |
R-22 |
CHF2Cl |
0.055 |
1.700 |
|
HCFC-124 |
R-124 |
CF3CHClF |
0.03 |
480 |
|
HCFC-142b |
R-142b |
C2H3F2Cl |
0.065 |
2.000 |
|
HFC-23 |
R-23 |
CHF3 |
0 |
11.700 |
|
HFC-32 |
R-32 |
CH2F2 |
0 |
650 |
|
HFC-125 |
R-125 |
C2HF5 |
0 |
2.800 |
|
HFC-134a |
R-134a |
CH2FCF3 |
0 |
1.300 |
|
HFC-143a |
R-143a |
CF3CH3 |
0 |
3.800 |
|
HFC-152a |
R-152a |
C2H4F2 |
0 |
140 |
|
HFC-227ea |
R-227ea |
C3HF7 |
0 |
2.900 |
|
PFC-14 |
R-14 |
CF4 |
0 |
6.500 |
|
PFC-116 |
R-116 |
C2F6 |
0 |
9.200 |
|
PFC-218 |
R-218 |
C3F8 |
0 |
7.000 |
|
Isobutane (HC-600a) |
R-600a |
CH(CH3)3 |
0 |
3 |
|
Propane (HC-290) |
R-290 |
C3H8 |
0 |
3 |
|
Ethane (HC-170) |
R-170 |
C2H6 |
0 |
3 |
|
Ethene (Ethylene) |
R-1150 |
CH2CH2 |
0 |
3 |
|
Propylene (HC-1270) |
R-1270 |
C3H6 |
0 |
3 |
|
Ammonia |
R-717 |
NH3 |
0 |
0 |
|
Carbondioxide |
R-744 |
CO2 |
0 |
1 |
|
Air |
R-729 |
- |
0 |
0 |
|
Water |
R-718 |
H2O |
0 |
0 |
|
R-No. |
Substances |
GWP-value (100 yrs) |
Concentration in weight-% |
|
R-401A |
HCFC-22/HFC-152a/HCFC-124 |
1082 |
53/13/34 |
|
R-402A |
HCFC-22/HFC-125/HC-290 |
2326 |
38/60/2 |
|
R-403A |
HCFC-22/PFC-218/HC-290 |
2675 |
75/20/5 |
|
R-403B |
HCFC-22/PFC-218/HC-290 |
3682 |
56/39/5 |
|
R-404A |
HFC-143a/HFC-125/HFC-134a |
3260 |
52/44/4 |
|
R-406A |
HCFC-22/HC-600a/HCFC-142b |
1755 |
55/4/41 |
|
R-407C |
HFC-32/HFC-125/HFC-134a |
1526 |
23/25/52 |
|
R-408A |
HCFC-22/HFC-143a/HFC-125 |
2743 |
47/46/7 |
|
R-409A |
HCFC-22/HCFC-142b/HCFC-124 |
1440 |
60/15/25 |
|
R-410A |
HFC-32/HFC-125 |
1725 |
50/50 |
|
R-412A |
HCFC-22/HCFC-142b/PFC-218 |
2040 |
70/25/5 |
|
R-413A |
HFC-134a/PFC-218/HC-600a |
1774 |
88/9/3 |
|
R-414A |
HCFC-22/HCFC-124/HCFC-142b/HC-600a |
1329 |
51/28.8/16.5/4 |
|
R-415A |
HCFC-22/HFC-23/HFC-152a |
1966 |
80/5/15 |
|
R-No. |
Substances |
GWP-value (100 yrs) |
Concentration in weight-% |
|
R-502 |
CFC-115/HCFC-22 |
5576 |
51/49 |
|
R-507 |
HFC-143a/HFC-125 |
3300 |
50/50 |
|
R-508A |
HFC-23/PFC-116 |
10175 |
39/61 |
|
R-508B |
HFC-23/PFC-116 |
10350 |
46/54 |
|
R-509A |
HCFC-22/PFC-218 |
4668 |
44/56 |
Appendix B: Commercial refrigeration systems
The commercial refrigeration systems installed in retail
stores, supermarkets, restaurants, computer centres etc.
account for the most important economic area within the
refrigeration industry. In addition, the widest range of
applications lies within this area. On this background
various conditions like prices, energy consumption,
refrigerant leakage and the TEWI value (Total Equivalent
Warming Impact) will be elucidated in this appendix.
In chapter B.1 a price comparison between liquid chillers
using R-404A, hydrocarbons and ammonia is made, whereas
conditions like energy consumption, refrigerant leakage and
the TEWI value for supermarkets systems are addressed in
chapter B.2. In chapter B.3 detailed price differences
between a traditional refrigeration system and a similar
refrigeration system using hydrocarbon refrigerant are
shown.
B1. Comparison of prices between ammonia, hydrocarbon and HFC refrigeration systems (liquid chillers)
The comparison will be based on liquid coolers (chillers)
and on this background price differences and the reason for
such will be analysed. An estimate of how prices are
expected to develop in the future is given.
Today HFC and ammonia refrigeration systems are produced in
large quantities. Basically, the HFC refrigeration systems
use the same technology as CFC and HCFC refrigeration
systems, and ammonia refrigeration systems have been
produced for more than 100 years. Recently, ammonia has been
replaced by artificial refrigerants, however application of
ammonia is rapidly in progress within the field of large
liquid coolers, air conditioning etc.
Compared to this, the use of hydrocarbons is relatively new
within the area of commercial refrigeration systems. Some of
these are produced in Sweden and Germany, where quite a
number of refrigeration systems operating on propane or
propene has been installed. These systems are produced in
small quantities and compared to HFC refrigeration systems
prices continue to be relatively high. A rapid improvement
of competitiveness could be possible.
Haukås
A report for SFT, Norway (Report 97:32, SFT) has been
prepared by Hans T. Haukås. This report includes
prices on various types of refrigeration systems.
According to Haukås the following prices for systems
over 10 kW are to be taken into consideration:
- a 12.5% price increase for refrigeration systems using
HFC-134a compared to systems using R-404 or R-507
- a 10-40% price increase for liquid cooling aggregates
using ammonia or hydrocarbons compared to systems using
R-404A or R-507
- application of ammonia or hydrocarbon requires a certain
extra charge for machine room safety
According to Haukås, the figures should be regarded as
guides and some examples deviate on both sides of the scale.
As far as large refrigeration systems are concerned,
application of ammonia will be directly competitive. No
investigation has been carried out as far as application of
hydrocarbons is concerned.
Grødem
In the trade magazine ScanRef (Scandinavian Refrigeration
3/98) Bjørn Grødem, also from Norway, states
that the above price differences are somewhat lower.
Grødem=s statement is based on German investigations
of refrigeration systems for supermarkets, where comparisons
between indirect cooling with R-404A, ammonia and
hydrocarbons have been made. Prices have been compared with
a direct R-404A refrigeration system as well.
Table B.1: Price comparison between different types of
supermarket systems. According to Grødem, ScanRef
3/98. Index 100 is the value for direct cooling with
R-404A.
|
|
Direct system using R404a |
Indirect system using R-404A |
Indirect system using ammonia |
Indirect system using propane/ |
|
Pipe system |
15% |
25-30% |
25-30% |
25-30% |
|
Refrigeration cabinets and air coolers |
45% |
45% |
45% |
45% |
|
Refrigeration system |
20% |
25% |
34-40% |
23-28% |
|
Refrigerant, oil and brine |
2% |
2% |
2% |
2% |
|
Control and electrical installation |
15% |
15% |
16% |
17% |
|
Planning |
3% |
3% |
3% |
3% |
|
Price |
100% |
115-120% |
125-135% |
115-125% |
Estimation of prices for hydrocarbon refrigeration systems
In co-operation with Alexander C. Pachai, AirCon A/S, Denmark, DTI Energy has made an analysis of future prices for hydrocarbon systems compared with a similar HFC refrigeration system.
The analysis assumes a large-scale production of the hydrocarbons systems similar to the present production of HFC refrigeration systems, thus achieving large-scale production benefits. The analysis also assumes that authorities have issued explicit guidelines on the building of hydrocarbon systems and that fitters have been properly trained in handling hydrocarbons. These requirements prevail in Sweden, where the company Bonus Energy AB builds hydrocarbon refrigeration systems, but not in other Nordic countries.
Components
Most of the components used in a hydrocarbon system are similar to the ones used in an HFC refrigeration system, and thus the price level will be identical. However, a certain price difference prevails for automatic controls. Application of explosion-safe components like differential pressure controllers, thermostats, terminal boxes, relays and ventilators, registered in the IP 44 safety category, is demanded. In Denmark the IP 23 safety category is normally used for commercial refrigeration systems, but this category is not sufficient for use of hydrocarbons. An example of a 14 kW refrigeration system is shown in chapter B.3, where the prices of component are shown as well. From this example a 4.3% price difference occurs, however this difference will be reduced for large systems.
Assembling
In hydrocarbon systems all joints and connections must be soldered. HFC refrigeration systems may be connected either by means of soldering or by use of screw fittings. Although the soldering process will require more working hours, this is expected to be equalised by decreased material consumption (i.e. screw fittings). Additional costs are expected in the range of 0 - 1%. The time used for leak detection is similar to that used for an HFC refrigeration system.
Safety
In the case of indoor machine room installation of the refrigeration system, the presence of a gas alarm at ground level is required. In case of outdoor or semi-roof installation, this precaution may not be necessary. The same requirements are valid for an HFC refrigeration system, which ought also to include a refrigerant leakage detector. The price for a gas alarm and the associated ventilator amounts to approximately DKK 6000 (list price).
Education
To secure that fitters are duly skilled for proper handling of hydrocarbons, establishment of a training system is required. Until now this is only the case in Sweden.
Equipment
For proper hydrocarbon handling, the assembling company needs suitable equipment.
The price of a hydrocarbon leak detector is almost similar to the one required for artificial refrigerants, e.g. HFC, which is also the case with a hydrocarbon charging aggregate. In addition, an explosion-safe vacuum pump is required, the price of which will be approximately 50% higher than the price of a traditional pump (list price is approximately DKK 7150).
For some time, the Danish transport requirements for pressure bottles containing hydrocarbon refrigerant have been the cause of confusion. According to previous advice issued by the Danish Society for Gas Technology, gas bottles should be placed in safety rooms in the service cars. Consequently, the requirements will differ from those of other gas bottles, e.g. acetylene for welding and soldering processes. At the moment, DTI Energy is investigating these requirements.
Conclusion
It has been concluded that the price of hydrocarbon systems is somewhat higher than that of similar HFC refrigeration systems. The price difference ranges between 10-40%, however, nothing will prevent a significant decrease of this in the future. Compared to a HFC refrigeration system, components for a 14 kW output hydrocarbon system are about 5% more expensive. In addition, due to the assembling process a 1% price increase will appear, including a possible additional charge for detector installation. However, use of detector is also recommended for HFC refrigeration systems.
Supermarket hydrocarbon refrigeration must be carried out by means of indirect cooling. Thus, the difference from an HFC refrigeration with direct system systems becomes more significant.
Estimation of future prices for ammonia refrigeration systems
Today ammonia refrigeration systems are competitive when taking systems larger than 100 kW into consideration. However, this is not yet the case with small and medium sized refrigeration systems, a fact, which can be changed. Not until recently has the use of ammonia in small and medium sized refrigeration systems been in focus and the number of available compressors is increasing.
However, the price level of these continues to be higher compared to prices of similar compressors for HFC refrigerants, but it is likely to believe that price equalisation will be generated by means of production of larger quantities. Furthermore, as far as pipe systems are concerned, new assembling methods are being developed to obtain lockring or fittings as an alternative to soldering.
B.2 Energy consumption and TEWI for commercial refrigeration systems based on supermarket refrigeration systems
From January 1994 the assembling of new commercial
refrigeration systems using CFC refrigerant (CFC-12, R-502
etc.) was prohibited in Denmark. In new refrigeration
systems the use of HCFC will be prohibited from January
2000. From January 2002 this will include application of new
HCFC for service purposes as well.
Hence, HFC based refrigerants including HFC-134a, R-404A or
possibly R-407 are used in most of the new supermarket
cooling cabinets and other commercial refrigeration
systems.
Direct cooling is used in supermarkets in Denmark and
Norway, whereas the use of indirect cooling is becoming more
frequent in Sweden, Germany and other countries. In Sweden
new supermarket refrigeration systems must be provided with
indirect cooling. According to the Swedish Refrigeration
Standard, a partly indirect refrigeration system is required
for filling charges between 10 and 30 kg. Traditionally, an
indirect system will be used for cooling and a direct system
will be used for freezing.
Filling charges over 30 kg require a completely indirect
system, i.e. indirect systems for both cooling and
freezing.
For direct supermarket cooling, liquid refrigerant will flow
in long pipe systems to the cooling places, e.g. cooling or
freezing storage, milk cooling cabinets, cold stores etc.
Afterwards the evaporated refrigerant is led back in other
pipe systems. In a medium sized supermarket, with cooling
required at 30-40 different locations, there are often
kilometres of refrigerant pipes and hundreds of pipe
connections.
A certain amount of leakage is almost impossible to avoid in
these pipe systems. Leakage will often occur in valve
gaskets and connections, or by direct accident caused by
broken pipes. Previously, the assumed leakage rate of these
systems amounted to 20-30% of the annual filling charge.
Great efforts have been made within the trade to improve the
quality of new systems, and hence a considerable reduction
of the leakage rate is assumed. IPCC's guidelines from 1996
state an annual average leakage rate of 17%. However, a 100%
tightness of the systems is not technically possible. The
exact figures are not known, however an annual 10% leakage
rate for supermarket systems with direct cooling is
assumed.
It is less expensive to produce a refrigeration system with
direct cooling than a similar system using indirect cooling.
According to Haukås the price is 20% higher, whereas
Grødem mentions a 15-20% price increase of the
indirect system.
This price difference is due to the slightly higher prices
for pipe systems. Investment in circulation pumps for the
secondary refrigerant is necessary. In addition, investment
in additional heat exchangers between the primary and
secondary system is required.
On the other hand a considerably smaller amount of
refrigerant is required (often 15-20% depending on the
amount in a direct system) and the leakage rate will be much
less, often only 5%.
Energy consumption
The precise energy consumption in the various systems is
hard to predict, as it depends on the retrofitting rate of
the individual systems. However, Bjørn Grødem
has tried to estimate some figures in ScanRef 3/98, which
are as follows:
Table B.2: Energy consumption for different supermarket
refrigeration systems. The source is similar to that used in
table B.1. However, it should be emphasised that this
example is not necessarily valid for all systems.
|
|
Direct system using R404A |
Indirect system using R404A |
Indirect system using propane/ |
Indirect system using NH3 (ammonia) |
|
Estimated energy consumption |
100% |
110% |
108% |
105% |
It is estimated that the design of hydrocarbon refrigeration systems soon will result in energy consumption for indirect systems, which does not exceed the consumption for direct systems. Use of components (compressors), which have been optimised according to the refrigerant, is required. Previously, R-22 components for propane or propene have been used. Through this optimisation the difference between direct HFC systems and indirect hydrocarbon systems will be significantly less.
New secondary refrigerants will be available on the market in the future, including ice slurry for refrigeration purposes and CO2 for freezing purposes. Hence, in comparison with direct HFC systems an improvement of the energy consumption used for indirect systems using ammonia or hydrocarbons is expected.
Contribution to the green house effect, TEWI
Refrigeration systems contribute both directly and indirectly to the green house effect. Direct contribution is caused by leak of refrigerant, e.g. R-404A, which has a GWP (Global Warming Potential) of 3260, compared to CO2, which has a GWP of 1.
The indirect contribution derives from electricity consumption. If electricity is generated at coal fired power plants, as is the case in Denmark, the CO2 emission from the power plant's stack corresponds to 0.8 kg of CO2 per kWh of electricity.
The TEWI value (Total Equivalent Warming Impact) combines both direct and indirect contributions, i.e.:
TEWI = GWP * M + ALFA * E
where
GWP is the GWP factor of the refrigerant;
M is the amount of refrigerant, leaking from the refrigeration system;
ALFA is the amount of CO2, which is generated during electricity production (kg of CO2 per kWh);
E is the electricity consumption of the refrigeration system.
Example
An example of a typical supermarket refrigeration system is given below. The example, which is typical for countries with direct cooling as standard, comprises a medium sized supermarket (e.g. Danish supermarket such as >Kvickly=, >Føtex=) with a sales area of 1000-1500 m2.
The total refrigeration efficiency is 100 kW and the system is provided with direct cooling. The refrigerant charge is 300 kg of R-404A.
The annual energy consumption of the refrigeration system is 170,000 kWh, whereas the leakage rate is 10% of the annual charge, i.e. 30 kg.
TEWI calculation stating yearly operation of the refrigeration system:
Direct yearly contribution to the green house effect:
M * GWP = 30 kg of R-404A * 3260 (kg of CO2/kg of R-404A) = 97800 kg of CO2 = 97.8 tonnes of CO2.
Indirect contribution to the green house effect: ALFA * E = ALFA * 170,000 kWh.
Table B.3: Contribution to the green house effect for the refrigeration system stated in the example. This example is for direct cooling with R-404A.
|
|
ALFA |
Indirect contribution to the green house effect
(kg of CO2) |
Direct contribution to the green house effect
(kg of CO2) |
TEWI for one year (kg of CO2) |
|
Coal-firing |
0.8 |
136.000 |
97.800 |
233.800 |
|
100% hydro- |
0 |
0 |
97.800 |
97.800 |
|
50% coal power + 50% hydroelectric power |
0.4 |
68.000 |
97.800 |
165.800 |
In the example with 50% coal and 50% hydroelectric power supply the share accounts for 59%. According to the example the share of hydroelectric power supply accounts for 100%. It should be mentioned that other environmentally related problems occur in connection with hydroelectric and nuclear power. In this example only the green house effect is included.
It has often been said that the refrigerant share of the TEWI value is very limited. However, this does not seem to be the case with supermarket refrigeration systems using R-404A and direct cooling. The refrigerant accounts for a considerable share of the total impact of the green house effect.
When using a hydrocarbon or an ammonia refrigeration system in the same supermarket, a considerably lower green house impact will be achieved, despite the small increase of energy consumption shown in the following table.
Table B.4: The TEWI value for a supermarket refrigeration system using propane and indirect cooling, c.f. table B.3. It should be mentioned that calculations are only related to the contribution to the green house effect. This example may not necessarily be representative for other commercial refrigeration systems.
|
|
ALFA (kg of CO2/kWh) |
Indirect contribution to the green house
effect |
Direct contribution to the green house
effect |
TEWI |
TEWI (R290) / |
|
Coal-firing |
0.8 |
146.880 |
0 |
146.880 |
0.63 |
|
100% hydroelectric |
0 |
0 |
0 |
0 |
0 |
|
50% coal- |
0.4 |
73.440 |
0 |
73.440 |
0.44 |
B.3 Differences in traditional and in hydrocarbon refrigeration systems
In this chapter the price differences between components
for HFC and hydrocarbons systems are described.
Components in a traditional refrigeration system
The design of a traditional refrigeration system is often
very simple. In many cases a thermostat equipped with an
on/off signal is used. If the system is provided with an
air-cooled condenser, application of a differential pressure
controller to obtain suitable condensing pressure during
cold intervals is frequently used.
Most of the components that can ignite a spark are
categorised under the protection classification IP 23 or the
like, which also implies fans. In many cases the terminal
box of the compressor, which contains the starting relay or
other relays than can cause a spark, are included as well.
In Denmark no rules concerning the application of twin
diaphragm differential pressure control for chemical
refrigerants prevail. As a consequence, these are not
commonly used, although their application may reduce
emission of potent green house gases. This is also the
explanation of their extent of use in Germany.
Price differences between IP 23 and IP 44 or above
In connection with hydrocarbon refrigeration systems it is
required as a minimum that equipment is categorised under
the safety classification of at least IP 44 or even above.
IP 54 and IP 55 are becoming a standard, wherefore products
of this class are normally easily obtained.
The definition of safety classification requires some
knowledge about the relevant nomenclature. Briefly, on a
scale from 0 to 6 the first number indicates dust-proofness.
The second number indicates water-proofness also on a scale
from 0 to 6. Thus, an apparatus categorised under IP 23 is
not quite dustproof and will only tolerate water spray,
whereas an apparatus under IP 66 remains tight when exposed
to water through a certain period and depth. Further details
concerning this matter is described in an European
standard.
Considering the system mentioned in the example, prices are
indicated in the following table for a system provided with
a suitable casing and improved level of safety.
Table B.5: Comparison between components for a
traditional HFC refrigeration systems and similar
hydrocarbon systems. The refrigeration performance is app.
14 kW.
|
Component |
List price |
Alternative |
List price |
|
KP 15 Flare (pressure controller) |
DKK 483.00 |
KP 17 W Soldered |
DKK 700.00 |
|
KP 5 Flare (pressure controller) |
DKK 261.00 |
KP 7 W Soldered |
DKK 474.00 |
|
KP 73 (2 pcs.) |
DKK 742.00 |
RT 2 (2 pcs.) |
DKK 1,640.00 |
|
Compressor aggregate |
DKK 24,992.00 |
Same |
DKK 24,992.00 |
|
TAU plate heat exchanger |
DKK 4,330.00 |
Same |
DKK 4,330.00 |
|
Total price |
DKK 30,808.00 |
Total price |
DKK 32.136.00 |
Whereas the price of some components in the high protection class is more than twice as much as the others, the most expensive components in the system are not more expensive, thus eliminating to some degree the price difference. The same type of components is used despite the size of system. Should the price of compressor, condenser and evaporator be more than doubled, the additional price for the subcomponents will be insignificant compared to the total price. According to the example, only a 5% price difference for the components alone is registered.
However, it should be emphasised that apart from Sweden the end-users in the Nordic countries may choose between an HFC refrigeration system with direct cooling and a hydrocarbon using indirect cooling. In this case the price difference will be higher, see table B.1.
As Swedish systems traditionally use indirect cooling. a lower price difference will be registered in this case.
Appendix C: Sabroe Chillers with NH3 refrigerant, installed in Denmark 1990-1998
|
|
Installed |
Refrigeration capacity |
|
Lego A/S,Billund |
1990 |
2.000 kW |
|
Grindsted Products,Grindsted |
1990 |
470 kW |
|
Statens Seruminstitut,Copenhagen |
1990 |
125 kW |
|
The Copenhagen Mail Centre,Copenhagen |
1992 |
800 kW |
|
Novo Nordisk,Kalundborg + 5 other chillers |
1992 |
2.800 kW |
|
MD Foods, Troldhede Dairy,Troldhede |
1993 |
55 kW |
|
MD Foods,HOCO,Holstebro |
1993 |
2.000 kW |
|
SAS Data,Kastrup |
1993 |
2 x 155 kW |
|
Panum Institute,Copenhagen University |
1993 |
920 kW |
|
National Hospital of Denmark,Copenhagen |
1993 |
1.000 kW |
|
Toyota,Middelfart |
1993 |
360 kW |
|
Scandinavian Center,Århus |
1993 |
1.000 + 800 kW |
|
SAS Data,Copenhagen |
1994 |
155 kW |
|
Danaklon,Varde |
1994 |
520 kW |
|
Dandy,Vejle |
1994 |
3 x 1.000 kW |
|
EAC,Head Office,Copenhagen |
1994 |
1.100 kW |
|
Copenhagen Pectin,Lille Stensved |
1994 |
230 kW |
|
Novo Nordisk,Kalundborg |
1994 |
340 kW |
|
SAS Data,Kastrup |
1994 |
2 x 155 kW |
|
Rødovre Skating Rink,Rødovre |
1994 |
500 kW |
|
SDC of 1993 A/S, Ballerup |
1994 |
1.600 kW |
|
Dandy,Vejle |
1995 |
800 kW |
|
Danish National Television,Head Office,Cph. |
1995 |
850 kW |
|
Copenhagen Airport,Copenhagen |
1995 |
1.066 kW |
|
Magasin (Dept. Store),Aalborg |
1995 |
528 kW |
|
Schou-Epa (Dept. Store),Roskilde |
1995 |
175 kW |
|
Lundbech A/S,Lumsås |
1995 |
500 kW |
|
Løvens Kemiske Fabrik,Ballerup |
1995 |
174 kW |
|
Faxe Kalk,Fakse |
1995 |
686 kW |
|
PBS Finans A/S,Ballerup |
1995 + 1997 |
640 kW |
|
Schouw Packing A/S,Lystrup |
1995 |
397 kW |
|
Pharmacia,Køge |
1995 |
76 kW |
|
NKT Project Center,Kalundborg |
1995 |
340 kW |
|
Aalborg Storcenter (Dept. Store),Aalborg |
1995 |
2.530 kW |
|
Nordisk Wawin A/S,Hammel |
1996 |
200 kW |
|
Novo Nordisk,Gentofte |
1996 |
100 kW |
|
Kastrup Stationsterminal,Kastrup |
1996 |
804 kW |
|
Novo Nordisk,Gentofte |
1996 |
1.096 kW |
|
J & B Enterprise A/S,SID Building |
1996 |
162,4 kW |
|
Novo Nordisk (building 3A-Ba),Bagsværd |
1996 |
370 kW |
|
Novo Nordisk (building AE-KA),Bagsværd |
1996 |
200 kW |
|
Danisco Foods A/S,Odense |
1996 |
220 kW |
|
SDC of 1993 A/S, Ballerup |
1996 |
1.588 kW |
|
Copenhagen Airports,Copenhagen |
1996 |
185 kW |
|
Risø National Laboratory,Roskilde |
1996 |
1.820 kW |
|
Codan Gummi A/S,Køge |
1996 |
175 kW |
|
Magasin du Nord (Dept. Store),Copenhagen |
1996 |
528 kW |
|
Glent Novenco,Åbyhøj |
1996 |
50 kW |
|
Superfos Packing A/S,Hårby |
1996 |
495 kW |
|
Dandy,Vejle |
1996 |
3.560 kW |
|
Palsgård Industri A/S,Juelsminde |
1996 |
25 kW |
|
Aarhus Oliefabrik A/S,Aarhus |
1996 |
406 kW |
|
Danisco A/S,Copenhagen |
1996 |
270 kW |
|
H. C Ørsted Institute,Copenhagen University |
1996 |
254 kW |
|
Eberhart A/S,Engesvang |
1996 |
261 kW |
|
Danisco Ingredients,Copenhagen |
1996 |
45 kW |
|
Kastrup Skating Rink,Kastrup |
1996 |
583 kW |
|
Lundbech A/S,Valby |
1997 |
500 kW |
|
Hvidovre Hospital,Hvidovre |
1997 |
2 x 2.543 kW |
|
Nordisk Wavin,Hammel |
1997 |
202 kW |
|
H.C. Ørsted Institute,Copenhagen University |
1997 |
254 kW |
|
Novo Nordisk,Bagsværd |
1997 |
200 kW |
|
Copenhagen Airports (Finger B),Copenhagen |
1997 |
2 x 804 kW |
|
Copenhagen Airports (Finger Vest),Copenhagen |
1997 |
900 kW |
|
Novo Nordisk,Hillerød |
1997 |
3.840 kW |
|
Delta A/S,Hørsholm |
1997 |
130 kW |
|
Ishøj Bycenter,Ishøj |
1997 |
1.030 kW |
|
Unibank,Christianshavn |
1997 |
538 kW |
|
Copenhagen Pectin A/S,Lille Stensved |
1997 |
530 kW |
|
Illum A/S (Dept. Store),Copenhagen |
1997 |
1.022 kW |
|
Scandic Hotel Copenhagen,Copenhagen |
1997 |
359 kW |
|
Tholstrup Gjesing A/S,Skanderborg |
1997 |
395 kW + 53 kW |
|
Tjæreborg Champinon,Tjæreborg |
1997 |
1.146 kW |
|
MD Foods,Troldhede Dairy, Rødkærsbro |
1997 |
240 kW |
|
Eghøj Champinon A/S,Veflinge |
1997 |
500 kW |
|
Danisco Distillers,Aalborg |
1997 |
9 kW |
|
FeF Chemicals A/S,Køge |
1997 |
68 kW |
|
Novo Nordisk - Building 3BM-Ba,Bagsværd |
1997 |
129 kW |
|
Phønix Contractors A/S,Vejen |
1997 |
575 kW |
|
SDC af 1993 A/S, Ballerup |
1997 |
505 kW |
|
Hørsholm Skating Rink,Hørsholm |
1998 |
370 kW |
|
Novo Nordisk A/S, Gentofte |
1998 |
1.670 kW |
|
Søndagsavisen,Copenhagen |
1998 |
80 kW |
|
Løvens Kemiske Fabrik,Ballerup |
1998 |
300 kW |
|
Nordisk Wawin,Hammel |
1998 |
220 kW |
|
Schulstad,Holstebro |
1998 |
290 kW |
|
Løvens Kemiske Fabrik,Ballerup |
1998 |
320 + 120 kW |
|
Birch & Krogboe A/S,Virum |
1998 |
390 + 50 kW |
|
MD Foods,Bislev,Bislev |
1998 |
1.500 kW |
|
Albani,Odense |
1998 |
270 kW |
|
Mejeriernes Produktionsselskab,Esbjerg |
1998 |
400 kW |
|
Hvide Sande Fiskeriforening,Hvide Sande |
1998 |
100 kW |
|
Løvens Kemiske Fabrik,Ballerup |
1998 |
2 x 214 kW |
|
Copenhagen Airports,Copenhagen |
1998 |
660 kW |
|
Novo Nordisk A/S,Kalundborg |
1998 |
100 kW + 2 x 400 kW |
|
Tulip,Århus |
1998 |
70 kW |
|
Scandinavian Air Lines,Copenhagen |
1998 |
160 kW |
|
Ørbæk Most,Ørbæk |
1998 |
120 kW |
|
Danexport,Hobro |
1998 |
650 kW |
|
Marine Biologisk Institut |
1998 |
2 x 30 kW |
Appendix D: Gram Chillers (York International) with NH3 refrigerant, installed in Denmark 1992-1998
|
|
Prodution |
Refrigeration capacity |
|
Force Institutes |
Containerised water chiller for process chilling
of welding machines |
200 kW |
|
Esbjerg Thermoplast |
Water chillers for process chilling of plastic
moulding plant |
2 x 187 kW |
|
Sun Chemical |
Water chillers for process chilling in chemical
industry |
235 kW |
|
Magasin Department Store |
Water chiller for A/C |
2 x 907 kW |
|
Vellev Dairy |
Brine (glycol) chiller for process chilling (ice
water) |
225 kW |
|
Chr. Hansens Lab. |
Walter chiller for process chilling of
pharmaceutical laboratories |
407 kW |
|
Tele Danmark |
Water chiller for A/C of main telephone
central |
3 x 232 kW |
|
Danish State Hospital |
Brine (glycol) chiller for refrigeration &
freezing of central kitchen facilities |
52 kW |
|
Magasin Department Store |
Water chiller for A/C |
1.449 kW |
|
Esbjerg City Hall |
Water chiller for A/C |
540 kW |
|
County Data |
Water chillers for A/C |
2 x 195 kW |
|
Frederiksberg Hospital |
Water chiller for A/C |
322 kW |
|
Esbjerg Hospital |
Water chiller for A/C |
2 x 554 kW |
|
Esbjerg Hospital |
Water chiller for A/C |
868 kW |
|
Panther Plast |
Water chillers for process chilling of plastic
moulding plant |
2 x 602 kW |
|
Printca |
Water chillers for process chilling in
pharmaceutical industry |
322 kW |
|
ATP House |
Water chiller for EDP cooling and
ventilation |
180 kW |
|
Berlingske Newspaper- Production |
Water chillers for A/C |
2 x 919 kW |
|
H. Lundbeck |
Water chiller for process chilling in
pharmaceutical industry |
994 kW |
|
ATP House |
Water chiller for EDP cooling and
ventilation |
564 kW |
|
Copenhagen Airport |
Water chiller for ventilation in luggage
sorting |
350 kW |
|
Grundfos |
Containerised liquid chiller for test plant |
25 kW |
|
NeuroSerch A/S |
Water chiller for process chilling in
pharmaceutical industry |
400 kW |
|
Technos Schou A/S |
Brine chiller for process chilling at painting
production |
175 kW |
|
Jyske Avistryk A/S |
Water chiller for process chiller for printing
machines |
450 kW |
|
P-Industri |
Water chiller for plastics industry |
240 kW |
|
Sophus Berendsen |
Water chillers for ventilation |
284 kW |
Appendix E: Bonus Chillers with Hydrocarbon-refrigerant, installed in Sweden 1996-1998
|
|
Installed |
Refrigeration capacity |
|
Bäckhammars Bruk, Kristinehamn |
1996 |
19 kW |
|
Vasakronan Real estate, Norrköping |
1996 |
2 x 260 kW |
|
AG's Favör, Lund |
1996 |
3 x 192 kW |
|
AG's Favör, Lund |
1996 |
2 x 50 kW |
|
AG's Favör, Landskrona |
1996 |
2 x 128 kW |
|
AG's Favör, Landskrona |
1996 |
25 kW |
|
Ronneby Real Estate, Bräkne-Hoby |
1996 |
2 x 250 kW |
|
TA Hydronics, Göteborg |
1996 |
66 kW |
|
ABB Real Estate, Enköping |
1996 |
60 kW |
|
Pharmacia & Upjohn, Uppsala |
1996 |
40 kW |
|
The Birgitta Gymnasium, Örebro |
1996 |
10 kW |
|
Hållstugan Daycare center, Örebro |
1996 |
38 kW |
|
Melkers meat processing, Falun |
1996 |
76 kW |
|
Ljungby Hospital, Ljungby |
1996 |
2 x 298 kW |
|
Calor Gas, GB |
1996 |
2 x 600 kW |
|
NWT - Newspaper, Karlstad |
1996 |
2 x 298 kW |
|
SEAB Gävle, Gävle |
1996 |
20 kW |
|
Areng Spa, Italien |
1996 |
3 kW |
|
Binsell, Uppsala |
1996 |
46 kW |
|
AG's Favör, Helsingborg |
1997 |
4 x 120 kW |
|
AG's Favör, Helsingborg |
1997 |
3 x 228 kW |
|
Domus (COOP), Visby |
1997 |
2 x 40 kW |
|
Domus (COOP), Visby |
1997 |
2 x 126 kW |
|
ASSI Domän, Frövi |
1997 |
95 kW |
|
ASSI Domän, Frövi |
1997 |
28 kW |
|
Edbergs, Örebro |
1997 |
38 kW |
|
University of Luleå, Luleå |
1997 |
82 kW |
|
Akzo-Nobel, Ömsköldsvik |
1997 |
91 kW |
|
Volvo, Köping |
1997 |
6 x 336 kW |
|
Hällstugan Daycare center, Örebro |
1997 |
38 kW |
|
ASSI Domän, Frövi |
1997 |
95 kW |
|
ASSI Domän, Falum |
1997 |
82 kW |
|
ABB Atom, Västerås |
1997 |
164 kW |
|
Pastejköket, Tranås |
1997 |
3 x 216 kW |
|
SKV, Svängsta |
1997 |
10 kW |
|
County of Karlstad, Karlstad |
1997 |
2 x 260 kW |
|
Katedral gymnasium, Skara |
1997 |
111 kW |
|
IUC-Gymnasium,Katrineholm |
1997 |
20 kW |
|
Saluhallen, Uppsala |
1997 |
82 kW |
|
Saluhallen, Uppsala |
1997 |
54 kW |
|
ICA HQ, Västerås |
1997 |
190 kW |
|
Volvo Aero, Arboga |
1997 |
48 kW |
|
Volvo Aero, Arboga |
1997 |
95 kW |
|
Hospital of Skellefteå,
Skellefteå |
1997 |
2 x 260 kW |
|
Hospital of Skellefteå,
Skellefteå |
1997 |
2 x 56 kW |
|
Hospital of Skellefteå,
Skellefteå |
1997 |
8 kW |
|
Swedish Road Adm., Borlänge |
1997 |
2 x 56 kW |
|
ASSI Domän, Frövi |
1997 |
41 kW |
|
Ericsson, Ursviken |
1997 |
2 x 190 kW |
|
Swedish Army, Visby |
1997 |
111 kW |
|
County of Gävle, Bollnäs |
1997 |
4 x 520 kW |
|
County of Gävle, Bollnäs |
1997 |
34 kW |
|
TA Hydronics, Göteborg |
1997 |
69 kW |
|
Real Estate Company, Umeå |
1997 |
2 x 96 kW |
|
ASSI Domäm, Frövi |
1997 |
20 kW |
|
Hospital of Lindesberg, Lindesberg |
1997 |
20 kW |
|
Hospital of Söderhamn, Söderhanm |
1997 |
20 kW |
|
Swedish Road Adm, Örebro |
1997 |
170 kW |
|
Electrolux, Holland |
1997 |
5 kW |
|
University of Umeå, Umeå |
1997 |
10 kW |
|
Swedish Coast Artillery, Stockholm |
1997 |
2 x 56 kW |
|
Vombverket, Veberöd |
1998 |
2 x 160 kW |
|
Hospital of Linköping, Linköping |
1998 |
2 x 86 kW |
|
Swedish Radio, Luleå |
1998 |
122 kW |
|
Hospital of Sandviken, Sandviken |
1998 |
34 kW |
|
Country of Karlstad, Karlstad |
1998 |
122 kW |
|
Country of Karlstad, Karlstad |
1998 |
90 kW |
|
Umeå gymnasium, Umeå |
1998 |
2 x 138 kW |
|
ABB Atom, Västerås |
1998 |
21 kW |
|
House of Wasa, Örebro |
1998 |
2 x 180 kW |
|
Nestlé, Malmö |
1998 |
78 kW |
|
Unikum in Örebro, Örebro |
1998 |
2 x 244 kW |
|
Kv Sjövik, Stockholm |
1998 |
122 kW |
|
Country of Karlstad, Karlstad |
1998 |
60 kW |
|
ABB Atom, Västerås |
1998 |
180 kW |
|
Sparebanken, Köping |
1998 |
2 x 206 kW |
|
Kv Harren, Luleå |
1998 |
122 kW |
|
Expolaris, Skellefteå |
1998 |
38 kW |
|
University of Karlstad, Karlstad |
1998 |
34 kW |
|
University of Karlstad, Karlstad |
1998 |
147 kW |
|
Hospital of Ljungby, Ljungby |
1998 |
147 kW |
|
Vasakronan Real estate, Norrköping |
1998 |
122 kW |
|
TÜV-approval, Tyskland |
1998 |
90 kW |
|
Fire Brigade, Luleå |
1998 |
33 kW |
|
Sabroe + Søby, Danmark |
1998 |
90 kW |
|
|
|
[Front page] [Top] |