According to Automotive News, BMW will launch a hydrogen-fueled 7-Series next year. The limited production vehicle will be the latest hydrogen effort by the German automaker, which has been experimenting with hydrogen power since the late '70s. Unlike other automakers focusing on hydrogen fuel cells to harness hydrogen for automotive powertrains, BMW is putting considerable effort into hydrogen-fueled internal combustion engines, as a practical transition step while a better hydrogen distribution infrastructure is developed.

BMW is exhibiting a "bi-fueled" (hydrogen and gasoline) internal combustion engine this week at the 2006 Hydrogen Expo U.S. in California, along with an in-vehicle liquid hydrogen storage system. BMW claims 230 hp from its bi-fueled engine, with more power to come as the design is optimized. The 6-liter V12 used in BMW's hydrogen-fueled H2R land speed record car (pictured) developed about 285 hp.

The other critical element of the bi-fuel powertrain is on-board hydrogen storage. Liquid hydrogen is the most efficient form of the fuel, with the highest energy density, but it demands a storage system capable of maintaining temperatures at a frosty -253 deg C. BMW's high-tech "thermos bottle" solution uses multiple layers of synthetic foil under a high vacuum.

[Sources: BMW, Automotive News]