Samenvatting
The implementation of alternative-fuel, heavy-duty engines is promoted under the Clean Air Act of 1990. The move toward alternative fuels finds impetus from the emission-reducing properties of alternative fuels and the need to reduce dependence on foreign petroleum supplies. The widespread use of alternative fuels faces three major integration challenges: (a) the leading alternative fuels have handling requirements that are different from petroleum fuels, and some are hazardous; (b) some have low energy densities and, at current prices, are more expensive per diesel fuel-equivalent unit of energy; and (c) the United States lacks an adequate ready supply of alternative fuels, as well as a high-volume, nationwide distribution network.