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Handbook on environmental assessment of products
Once you know exactly what the product delivers to users and what its
secondary services are, you need to find out what the environmental impacts of the produc
are. The first step in this regard is to form an overview of the product life-cycle.
2.1 Define your task
A product life-cycle has five main phases: the raw materials phase, the
production phase, the use phase, the disposal phase, and the transport phase. Transport
can either be dealt with separately or be distributed among the other phases.
Begin by noting down the product life-cycle on a piece of paper. Try
to form an impression of the significant and insignificant issues associated with the
product life-cycle. Assess the total weight of the product and the types of raw materials
used. Consider whether production of the product might entail particularly problematic
processes or chemicals. Examples would be use of varnishes that emit solvents or
particularly energy-intensive processes such as enamelling.
Look at the product lifespan: for most products, the use phase is much
longer than the other phases. Thanks to modern technology, the total working time spent on
making a coffee maker is less than an hour, while its expected lifespan is five years,
perhaps even more. Try to apply proportions to the use phase. Consider the most likely
route of disposal of the product: which materials will be recycled? Which
Think about how you can get the data you need, and how you will go about
collecting data. You can use a chart such as the one for the coffee maker shown in table
2.1 as the basis for your deliberations and planning.
Table 2.1
Initial overview of the lifecycle of a coffee maker
Phase |
Description |
Where can data be
found? |
Raw
materials phase |
Total product weight: a
couple of kg.
Material contents: plastic, glass, steel, aluminium,
copper (in wires), materials for the heating element (?)
Packaging: cardboard (probably recycled). |
Production
department, raw materials and process lists. |
Production
phase |
Most significant
production processes: shaping the raw materials, e.g. aluminium moulding. Surface
treatment of steel parts.
Special processes/chemicals: heavy metals for surface
treatment. Possibly other processes as well check. |
Production
department, raw materials and process lists. Data on chemicals can also be found with the
environmental department// occupational health service. |
Use phase |
Life span: estimated at
five years on average.
Sales by markets/countries (>80%): Denmark, Sweden,
Norway, and Germany.
Operation
Operation data: a total of 2 x 7 x 52 x 5 = 3,640 litres
of coffee made. Total time per litre: approximately 12 minutes. The coffee is kept hot
(80ºC) for approximately 30 minutes on average.
Energy consumption: 3,640 litres of coffee is heated from
approximately 10ºC to boiling point. Heating losses from 1 litre of very hot water for a
total of 1,820 hours.
Raw materials consumption: 3,640 coffee filters and a
quantity of coffee.
Consumption of ancillary materials: no.
Maintenance
Energy consumption: decalcification involves heating of 2
litres of water to boiling point once a month (?)
Cleaning of pot and machine with warm water how
often?
Raw materials consumption: no.
Consumption of ancillary materials: vinegar (for
decalcification), soap/washing-up liquid (for cleaning). |
Sales and
marketing department
Dealers
Product-development department. |
Disposal phase |
Ways of disposal,
estimated average (%)
Disposal takes place through recycling stations or via
household garbage bins.
Landfills: estimated at 0%
Incineration: estimated at 100% of all machines and 50%
of all pots. Their energy content is utilised.
Shredding: estimated at 0%
Separation: estimated at 0%
Recycling: 50% of all glass pots are estimated to be
recycled
Other: estimated at 0% |
Possibly
the sales and marketing department and the product-development department.
Possibly with the local authorities, e.g. recycling
depots.
Possibly with knowledge institutes. |
Transport phase |
The coffee is
transported 10,000 km.
The raw materials for the coffee maker are transported
2,000 km to the manufacturer.
The finished coffee maker is transported 100 km to the
consumer. When the consumer eventually throws it out, it will be transported 5 km for
disposal. |
Possibly
with the sales and marketing department. |
Example B2.1: Sportswear
A company which manufactures sportswear switched to a type of fibre
which reduced energy consumption by half in the manufacturing process. This was regarded
as a considerable environmental improvement of the product. However, the company was
subsequently asked how many times the garments were washed and tumble dried throughout
their lifespan and about the differences between the old and new fibre types in terms of
their ability to retain water, hence their impact on the energy needed to tumble dry them.
It turned out that no account had been taken of this. |
Some products are "active" during the use phase, e.g. energyconsuming products
such as vacuum cleaners, computers, television sets, or pumps. For other products, the use
phase involves very frequent maintenance, e.g. textile products or tableware. For such
products, the use phase is almost always dominant. Other products are more
"passive", which is to say that they do not have the same degree of impact on
the environment during the use phase, e.g. furniture, newspapers, packaging, or paper
cups. Even passive products may, however, involve some environmental impact during the use
phase: furniture and other objects may need cleaning, maintenance, cooling, heating,
drying or similar, and they may exercise an indirect impact on the environment because
they form part of other systems. This is why you need to take a very careful look at the
entire product life-cycle, trying to imagine all the processes the product goes through
and the impacts it causes.
It can be difficult to obtain specific figures for disposal and transport. Waste from
private households is disposed of through standard household waste or via a recycling
depot. You can safely assume that all waste which is being disposed of as part of the
standard household waste will be incinerated 100%. For waste delivered to recycling
depots, you can use the values given in table 2.2. These values are approximate and should
only be used if you do not have more detailed information to hand from other sources.
Actual disposal will depend on factors such as:
| Opportunities for separation |
| Collection systems |
| Economically feasible reprocessing techniques |
Table 2.2
Rules of thumb for disposal routes for raw materials disposed of via recycling
depots
|
Incineration |
Reuse |
Landfilling |
Paper/cardboard (packaging) |
25 |
75 |
0 |
Plastic |
85 |
15 |
0 |
Metal |
0 |
100 |
0 |
Glass |
0 |
100 |
0 |
Non-flammable waste |
0 |
0 |
100 |
2.1.4 What should be included?
You will often have to decide whether you should include minor parts of the product in
your considerations, e.g. screws, oil, and similar. In the example of the coffee maker,
you may also want to include coffee filters and the coffee itself. If you are not sure
what to include, assume that anything which is influenced by the company's or the user's
choices must be included.
There are no fixed criteria to decide on what should
be included. What you need to do is to cover a significant part of the life-cycle. One
possibility is to look at the product weight. For example, you may decide that at least
95% of the product weight must be covered by the environmental assessment. However, even
small parts can contribute significantly to energy consumption and/or environmental loads,
so just looking at the weight is not enough. |
So we cannot say, for example, that screws should never be considered. If your
environmental assessment concerns a screw, it is obviously significant. If, however, you
have a product which contains 100 kg steel and has a chromium-plated surface, 20 grams of
steel screws do not make much difference. Omitting them from your assessment does not
matter, because steel does not contain scarce resources or hazardous/harmful substances.
2.2 Collect data for the product life-cycle
You now need to obtain data about the entire product life-cycle. For example, you may
want to collect data in tables to make them easily accessible to others. This will also
make it easier to show what you have included in your environmental assessment.
Information on raw materials and production will often be available from the company
production department. Many companies have a so-called raw materials and process list
which includes all the data you need. Information on where the product is sold is often
available from the sales and marketing department, while data on the actual use can be
collected from the sales staff and product-development staff alike. It will often be
necessary to obtain information on disposal of the product from other sources, e.g. from
the local recycling depots, from dealers (who sometimes receive returns of old product
when selling new ones), or from knowledge institutes.
Example B.2.2: The coffee
maker
The use phase: You might be able to get data on the use
process from the marketing department, but it will often be necessary to carry out
calculations on the basis of specifications and rating plates. The heating coil of the
coffee maker has an effect of 600 W, and it takes approximately 12 minutes to make 1 litre
of coffee. This means that the energy consumed to make coffee is 0.660 kW times 0.2 hours
times 3,640 litres, corresponding to around 440 kWh to make 3,640 litres of coffee
throughout the product lifetime. The effect of the hot plate is 55 W. Each pot of coffee
is kept warm for 30 minutes (on average), corresponding to 0.5 hours times 0.055 kW times
3,640 = 100 kWh. This equals an energy consumption of 100 + 440 = 540 kWh. You should also
remember that the coffee and coffee filters are part of the use phase. You may well ask
yourself if you really need to include these things when you are supposedly looking at the
coffee maker and the coffee maker is the only thing manufactured by your company. However,
as the choice of concept and construction of the coffee maker can affect the use of
filters and coffee, they do need to be included in the assessment so that we can see the
environmental consequences of any changes.
The disposal phase: Disposal can be presented as shown in
table 2.5. In this example, the entire product is sent for incineration via the standard
household waste, except the glass pots; we assume that 50% of all glass pots are recycled.
We will compensate for the recycled materials in our calculations of the total impact
assessment. The steel parts are assumed to be sent for incineration, but at the same time
half of this steel is assumed to be separated out on a sorting conveyor belt by means of
magnets. It will then be sent for recycling. The table includes the concept
"compensation" this will be explained later. |
Table 2.3
Composition of the coffee maker and the manufacturing processes associated
with it
Components |
Number |
Raw materials |
Weight |
Manufacturing
processes |
Ancillary materials |
Cabinet |
1 |
Plastic,
impactresistant polystyrene |
1.1 |
Die casting
Pressure-die |
Release agent |
|
1 |
Aluminium |
0.1 |
Casting |
Lubrication? |
|
1 |
Steel |
0.3 |
Sheet-metal
stamping
Punching |
? |
Wire |
1 |
Copper |
0.02 |
Wire drawing |
|
|
1 |
Plasticized PVC |
0.02 |
Coating |
|
Glass pot |
1 |
Glass |
0.34 |
Glass moulding |
|
Handle |
1 |
Plastic, impactresistant
polystyrene |
0.02 |
Die casting |
Release agent |
Clamp |
1 |
Aluminium |
0.01 |
Rolling |
? |
Packaging |
1 |
Cardboard |
0.39 |
- |
? |
Table 2.4
Use of the coffee maker
Material/
component |
Process |
|
|
Ancillary materials |
Name |
Unit |
Quantity |
Name |
Entire
product |
| Coffee-making
|
| Electricity consumption
|
| Coffee filters
|
| Coffee
|
| Water
|
|
|
|
- |
kWh |
540 |
- |
kg |
7.3 |
Bleach |
kg |
290 |
Pesticides/fertilizer |
kg |
3,640 |
- |
Cleaning (machine and pot) |
kg |
50 |
Water (hot/warm) |
ml |
25 |
Washing-up liquid |
Decalcification |
kg |
15 |
Acetic acid |
Compensation
for heating |
kWh |
-360 |
- |
Table 2.5
Disposal of the coffee maker
Component |
Process |
Ancillary material |
Share |
Name |
Unit |
Quantity |
Name |
Aluminium |
1 |
Waste incineration,
aluminium |
kg |
0.1 |
? |
Polystyrene |
1 |
Waste incineration,
polystyrene |
kg |
1.1 |
? |
|
1 |
Compensation
for heat generated by waste incineration |
kg |
-1.1 |
? |
Glass |
0.5 |
Waste incineration,
glass |
kg |
0.17 |
? |
|
0.5 |
Melting, glass |
kg |
0.17 |
? |
|
0.5 |
Compensation for glass |
kg |
-0.17 |
? |
Steel |
1 |
Waste incineration,
steel |
kg |
0.3 |
? |
|
0.5 |
Melting, steel |
kg |
0.15 |
? |
|
0.5 |
Compensation for steel |
kg |
-0.15 |
? |
Copper |
1 |
Waste incineration,
copper |
kg |
0.02 |
? |
Coffee filters |
1 |
Waste incineration,
coffee filters |
kg |
7.3 |
? |
|
1 |
Compensation
for heat generated by waste incineration |
kg |
-7.3 |
? |
Coffee grinds |
1 |
Waste
incineration, organic materials |
kg |
290 |
? |
|
1 |
Compensation
for heat generated by waste incineration |
kg |
-290 |
? |
Packaging |
1 |
Waste incineration,
cardboard |
kg |
0.39 |
? |
|
1 |
Compensation
for heat generated by waste incineration |
kg |
-0,39 |
? |
Include a conservative calculation of the significance of the total transport to get an
initial impression of whether transport is important to the overall situation. In most
cases, transport is not very important, and optimisation within this area can often be
left to the logistics department. Transport for the coffee maker is illustrated in table
2.6.
Table 2.6
Transport, coffee maker
Mode of transport |
Distance, km |
Quantity, kg |
Transport of coffee, ship |
10,000 |
90,0 |
Transport of raw materials for coffee maker, car |
2,000 |
2.3 |
Transport of coffee maker to user, car |
100 |
2.3 |
Transport of coffee maker for disposal, car |
5 |
2.3 |
Tables 2.3-2.6, illustrated here by our example of the coffee maker, form the basis for
your environmental assessment. They specify all the information you need about the product
and its life-cycle. You will often need various data, particularly in connection with
processes and ancillary materials this is also illustrated in the example of the
coffee maker. You will have to leave these matters aside for the present, but they should
still be included in your basis for future work, as they will be addressed at a later
stage.
It is important that you indicate very
clearly what you have included in your environmental assessment. Place checkmarks in your
tables or make a list of your omissions and assumptions. |
2.2.1 Would a flow diagram of the product life-cycle be more suitable?
Would a flow diagram of the product life-cycle be more suitable? The raw materials and
process list model can be useful for establishing an overview of the product life-cycle if
the product in question comprises many separate components and/or raw materials. For
simpler and more homogenous products, you can also choose to use a flow diagram. In some
cases, such a diagram provides a better overview. You are free to choose whatever you feel
is best in each case.
Figure 2.1
Overview of the coffee maker's life-cycle. Transport not included.
2.2.2 Compensation
In the previous section, we mentioned that the unintentional secondary services seen in
connection with most products often have considerable impact on the environment. This kind
of service appears where the system that you are looking (the product life-cycle and the
processes it includes) affects or is connected to other systems. Secondary services reduce
or eliminate the need for alternative ways of receiving the service in question. In order
to take this into account, we need to compensate for such services. If, for example,
metals are being recycled, you need to deduct production of a corresponding amount of
metal from the overall result. This means that for the purpose of calculations, you will
experience negative raw materials consumption during the disposal phase.
Compensation occurs most frequently within the following areas:
| Excess heat from electrical appliances and devices |
| Electricity and heating generated by means of waste incineration |
| Recycling |
Excess heat is typically encountered during the use phase and constitutes a negative
contribution. It is important to address excess heat separately, as this is one of the
areas where your work can make a difference. For coffee makers and water heaters, excess
heat represents the greatest scope for improvements.
In Denmark, the heat generated by incineration plants is utilised. The heat which can
be utilised corresponds to the calorific value of the materials. Plastic and papier are
high-grade fuels, while metals usually have no calorific value. The values can be found in
Appendix B, table 2.1.
When materials are recycled, this is indicated by placing a in front of the
recycled materials during the disposal phase. Remember to include energy consumption for
the recycling process in your calculations (e.g. melting). It is not enough to simply hand
over the materials; they also need to be processed.
Remember that compensation can only be carried out in situations where, for example,
materials are in fact recycled or are very likely to be recycled. It is not enough that
they can be recycled.
Table 2.7
A product contains 10 kg plastic, of which 5 kg are recycled
Example B2.3: Compensation
A product contains 10 kg plastic, of which 5 kg are recycled. |
|
The raw materials phase |
The disposal phase |
Raw materials |
10 kg plastic (resources) |
5 kg plastic (resources) |
Energy |
10 kg plastic (energy) |
Energy for reprocessing of 5 kg plastic |
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