Only 24 percent of consumers know what fuel-cell vehicles are, but 52 percent say they are likely to buy one next time they're in the market for a new car.

That is according to an online survey of more than 14,000 consumers by Harris Interactive Inc.

There is a catch to the enthusiasm for fuel cells, which convert hydrogen to electricity without producing pollution.

Respondents said they are willing to pay only $1,269 extra for the still-developing technology, a fraction of the current cost, which some automakers estimate is 10 or more times that of a conventional vehicle.

The cost of fuel cells is expected to decline as more are built.