Alcohol Fueled Heavy Duty Vehicles Using Clean, High Efficiency Engines*

*Supported by the John and Jane Bradley gift to the MIT Energy Initiative Ethanol and methanol derived from a variety of sources could make a substantial contribution to replacing oil-derived transportation fuels and reducing greenhouse gas emissions. Particularly important are next generation, low carbon biofuels derived from agricultural, forestry, municipal and industrial waste by biochemical or thermochemical processes including plasma gasification, as well as specially grown biomass such as switchgrass. Ethanol, methanol or mixtures of these fuels can be used in turbocharged direct injection spark ignition engines which are as or more efficient than diesel engines and also provide advantages of lower cost, lower emissions and higher power. The strong knock suppression resulting from direct alcohol injection enables engine operation with power densities of up to three times that which can be provided by diesel engines. A representative power density is 200 hp/liter. The introduction of these engines in heavy duty vehicles could be relatively rapid because of the need to replace present heavy duty diesel engines in order to meet more stringent air pollution regulations and relativel