SAN FRANCISCO– A new report issued by the National Research Council (NRC) said that fuel cells are still at least 15 years away from being commercially feasible. The release stated that despite "impressive progress toward commercialization," some $200 billion is needed over the next decade and half — $55 billion from the government and $145 billion from the private sector. In the short term, fuel efficiency and biofuel research would be a more cost-effective way to reduce transportation emissions, according to

The biggest obstacles for fuel cells are high vehicle costs and a lack of fueling infrastructure. At most, there will be only 2 million fuel cell-powered cars on American roads by 2020, representing less than 1 percent of the fleet, the NRC estimates.

The report's best-case scenario estimates fuel cell vehicles, including cell and refueling costs, will be cost-competitive on the passenger car level by 2023. From there, fuel cell adoption could explode, hitting 60 million in 2035 and 200 million by 2050.

The report makes clear just how complicated clean technology is. Cleantech projects have been plagued by delays and increasing expenses, especially in the automotive realm. But such is the nature of research in the areas of hard science and engineering and these risks should not be a surprise to investors.