Performance evaluation of alternative fuel/engine concepts
Task 5 within the IEA Agreement on Alternative Motor Fuels is the first subtask to generate new experimental data. The objective of the task is to generate information on the emission potential of alternative fuels in severe operating conditions and to evaluate new emission measurement methods. The work was carried out in three phases, Engine Tests (preliminary phase), Vehicle Tests and Addendum of Diesel Vehicles. The work was carried out at VTT (Technical Research Centre of Finland) as a cost shared operation.
The vehicle tests included 143 different vehicle/fuel/temperature combinations. FTP type emission tests were run on 14 vehicles fuelled with different gasoline compositions, methanol (M50 and M85), ethanol (E85), LPG, CNG and diesel. Both regulated and unregulated emission components were measured using the most up-to-date emission measurement technology.
The results indicated that today's advanced gasoline vehicles must be considered rather clean. Diesel is comparable with gasoline in the case of CO and HC. M85 gives low emissions in warm conditions, but unburned methanol must be controlled. Natural gas and LPG are inherently clean fuels which, using up-to-date engine technology, give low emissions in all conditions.