Environmental Project No. 1092 2006 – Fuel use and emissions from non-road machinery in Denmark from 1985-2004 - and projections from 2005-2030

Fuel use and emissions from non-road machinery in Denmark from 1985-2004 - and projections from 2005-2030

Summary

This report documents the updated 1985-2004 fuel use and emission inventory for non road machinery and recreational craft in Denmark. The inventory comprises the emission components of SO₂, NO_x, NMVOC, CH₄, CO, CO₂, N₂O, NH₃ and TSP, and in addition a fuel use and emission forecast is presented from 2005-2030. The calculated results are grouped into the sub-sectors agriculture, forestry, industry, household/gardening and inland waterways, according to the structure of the CollectER database used for all Danish sources.

The report explains the existing EU emission directives for non road machinery, the actual fuel use and emission factors used, sources of background and operational data, calculation methods and the calculated fuel use and emission results.

EU emission directives

The emission directives agreed by the EU relates to both diesel and gasoline fuelled non road machinery, and list specific emission limit values for NO_x, VOC (in some cases NO_x + VOC), CO and particulates. The specific limit values (g/kWh) depend on engine size (kW for diesel, ccm for gasoline) and date of implementation (referring to engine market date).

For diesel engines, the EU directives 97/68 (emission stage I and II) and 2004/26 (emission stage IIIA, IIIB and IV) relates to non road machinery other than agricultural and forestry tractors, whereas for tractors the relevant directives are 2000/25 (emission stage I and II) and 2005/13 (emission stage IIIA, IIIB and IV). For gasoline engines, the EU directive 2002/88 (emission stage I and II) distinguishes between hand held (SH) and not hand held (NS) types of machinery.

For recreational craft, the EU directive 2003/44 comprises emission legislation limits for diesel and for 2-stroke and 4-stroke gasoline engines, respectively. The CO and VOC emission limits depend on engine size (kW), whereas for NO_x, a constant limit value is given for each of the three engine types. For TSP a constant emission limit regards diesel engines only.

Fuel use and emission factors

The emission factors used in the Danish inventory are grouped into EU emission legislation categories. However, for engines older than directive first level implementation dates three additional emission level classes are added so that a complete matrix of fuel use and emission factors underpins the inventory.

Actual measured factors of fuel use and NO_x, VOC, CO and TSP emissions, predominantly come from IFEU (2004) together with factors for deterioration, transient engine loads and gasoline evaporation. EMEP/CORINAIR (2003) is the source of N₂O and NH₃ emission factors, whereas the CH₄/NMVOC split of VOC is taken from USEPA (2004). The determination of emission factors for future machinery is based on own judgement, taking into account today’s emission factors for new machinery and future EU emission legislation limits.

Stock and operational data

For agricultural tractors and harvesters, total fleet numbers and new sales/engine size figures are provided by Statistics Denmark and The Association of Danish Agricultural Machinery Dealers, respectively. The latter organisation has also provided new sales numbers for the most important types of construction machinery. Fork lift new sales/lifting capacity data is provided by IFAG. For household and gardening equipment and recreational craft, total stock numbers and engine sizes per machinery/vessel type have been assumed based on personal communication with people employed in relevant professional bodies, large engine manufacturers, research institutes etc.

Data for load factors, annual working hours and engine lifetime are primarily from the existing non road inventory model. However, in some cases data have been updated and/or new data added through discussions with external key experts for the relevant types of non road machinery.

Calculation procedure

The fuel use and emissions are calculated as the product of the number of engines, annual working hours, average rated engine size, load factor, and fuel use/emission factors. For diesel and gasoline engines, the deterioration effects (due to engine ageing) are included in the emission calculation equation by using deterioration factors according to engine type, size, age, lifetime and emission level. For diesel engines before Stage IIIB and IV, transient operational effects are also considered by using average transient factors.

The evaporation of gasoline hydrocarbon emissions is also estimated from the fuelling procedure and because of tank evaporation. The tank loading emissions are calculated as the product of total gasoline fuel use and evaporation factors (g NMVOC/kg fuel), whereas tank evaporation emissions are found as the product of engine numbers and evaporation factors (g NMVOC/year).

Fuel use and emission results

The diesel fuelled machinery in agriculture and industry are the most important sources of fuel use and emissions of SO₂, NO_x, CO₂, N₂O, NH₃ and TSP in 2004. Agricultural tractors is the most dominant single source, with fuel use and emission totals of around one third of the grand totals for land based non road machinery.

For diesel machinery as a total, the fuel use and emissions of SO₂, CO₂, NMVOC, CH4, CO and TSP decrease by 6, 91, 6, 43, 43, 33 and 54%, respectively, from 1985-2004. In the same time period the emissions of NO_x, N₂O and NH₃ increase by 4, 2 and 2%, respectively.

The trend in total diesel fuel use (and CO₂) is dominated by a decrease in fuel use for agricultural machinery, and an increase in fuel use especially for non road construction machinery and fork lifts. The significant SO₂ emission decline is caused by a large reduction of the sulphur content in non road diesel. For NO_x, the slight emission increase is due to the relatively large 1991-stage I emission factors, whereas the large emission reductions for NMVOC, CH₄, CO and TSP are due to the gradually improved engine emission techonology for these emission components.

The development towards cleaner diesel engines continues in the future, and for NO_x, NMVOC, CH₄, CO and TSP the total emissions are expected to decrease by 81, 78, 78, 63 and 85% from 2004-2030. This is due to the gradually strengthened future EU emission standards. A significant reduction of the sulphur content for diesel in 2005 cuts down the diesel related SO₂ emissions by as much as 98%. In the 2004-2030 time period a moderate decline in fuel use and CO₂, N₂O and NH₃ emissions is expected, mainly due to a decrease in the use of agricultural tractors.

Most of the NMVOC, CH₄ and CO emissions come from gasoline fuelled working machinery. Set in relation to the total land based non road emissions, the NMVOC emission share is 26% for chain saws used in forestry and for household, and for CH₄ and CO the emission shares for riders (private and professional) are 34 and 53%, respectively.

From 1985-2004 the emissions of NMVOC, CH₄ and CO from gasoline machinery increase by 18, 12 and 8%, respectively. From a broad perspective the engines have become more emission efficient, since the total gasoline fuel use has increased by 39% in the same time period. In the forecast period from 2004-2030 the gasoline related fuel use and emissions of NMVOC and CH₄ is expected to decrease by 5, 34 and 11%, respectively, whereas an emission increase of 9% is expected for CO. Here, small or zero emission factor reductions for stage I and II engines in combination with higher deterioration factors cause the CO emissions for gasoline machinery to increase even after the time of stage I and II engines entering the market.

For recreational craft, most of the fuel use, SO₂, NO_x, CO₂, N₂O, NH₃ and TSP emissions are attributed to the diesel engine category, while most of the NMVOC, CH₄ and CO emissions come from gasoline fuelled engines, as is the case for land based non road machinery. However, compared to the latter machinery group, the fuel use and emissions from sailing vessels are small.

From 1985 to 2004 there has been a large increase in sailing activities, most significantly for diesel fuelled boats, and a gradual shift from 2-stroke to 4-stroke technology for gasoline engines. These tendencies are reflected in the increases of fuel use (188%), N₂O (300%), NH₃ (258%), NO_x (239%), SO₂ (201%), CO₂ (189%), TSP (106%), CO (81%), CH₄ (75%) and NMVOC (13%). The overall diesel fuel increase is the main reason for the SO₂, NO_x, CO₂, N₂O, NH₃ and TSP emission growths, whereas the increase in gasoline fuel use explains the CO and CH₄ emission inclines. The small NMVOC emission increase is explained by the gasoline engine shift to the more environmentally friendly 4-stroke technology, since total gasoline fuel use has gone up with 50% from 1985 to 2004.

From 2004 to 2030 the emissions of NMVOC and CO are expected to decrease significantly due to the 2-stroke/4-stroke technology shift (NMVOC) and the relatively low future EU 2003/44 directive emission limit. The latter explanation also applies for the NO_x and TSP emission decreases, mainly driven by the emission trend for diesel fuelled boats.

Conclusion

The present project has provided valuable new Danish information for different types of non road machinery and recreational craft, in terms of stock and operational data, fuel use and emission factors, and calculated results. The new non road inventory model is facilitated to produce annual fuel use and emission estimates both for historical years and projection years in order to fulfil various national obligations.

An important outcome of the present study has also been the establishment of contacts with Danish experts dealing with statistical data and experts from research institutes, relevant professional bodies, machinery manufacturers, etc. It is the goal to obtain information of new sales and total stock on an annual basis, in order to ensure continuously updated inventories. To the extent that statistical numbers are produced, new sales figures for tractors, harvesters, construction machinery and fork lifts should be gathered together with total stock data for household/gardening machinery, and recreational craft.

On a European level, the purpose of the EMEP/CORINAIR guidebook published by the European Environment Agency is to provide inventory support for country estimates. However, the guidebook data are more than ten years old and consequently the demand for new data is becoming more and more urgent. The fuel use and emission data used in the German inventory (IFEU, 2004) and in the present report are able to solve this task, and work should therefore be made to include these data in the EMEP/CORINAIR guidebook.