The increasing emphasis placed by these stakeholders on alternative fuels and the vehicles that they power is quickly outpacing vehicle size and efficiency of combustion as the most promising source of mobile emission reductions.
The appearance of alternative fuel and alternative vehicle requirements in state and federal regulation, the rise in related corporate research and development expenditures, and the recent appearance of alternative vehicles in the marketplace, collectively indicate a long-term trend which may be the most significant single issue facing the automotive industry in the next two decades.