Science Daily — Imagine a vehicle that runs on hydrogen or biofuels and offers the same features, performance and price as today's gasoline vehicle. Will it capture half the market? Not likely, concludes a new MIT analysis of the challenges behind introducing alternative-fuel vehicles to the marketplace. Not even if it's three times more fuel-efficient.

Among the barriers: Until many alternative fuel (AF) vehicles are on the road, people won't consider buying one-so there won't be many on the road. Catch-22.

The researchers' conclusions are not all gloomy, though. If policy incentives are kept in place long enough, adoption will reach a level at which the market will begin to grow on its own. But "long enough" may be a surprisingly long time.