August 17, 2004
Metal-hydride hydrogen storage seen as practical alternative to gaseous hydrogen
Palm Desert, California – Texaco Ovonic Hydrogen Systems, a joint venture of Energy Conversion Devices, Inc. and ChevronTexaco Technology Ventures LLC, is developing a metal-hydride hydrogen storage system for a modified hydrogen-electric version of a popular hybrid sedan.
The modified hydrogen hybrid will be available for test drives at the South Coast Air Quality Management District’s “Hydrogen – Fuelling the Clean Air Future” conference today at the J.W. Marriott Desert Springs Resort in Palm Desert, California.
“We believe that one of the key enabling technologies for implementing the hydrogen economy … now … is our metal hydride storage solution,” says Bill Roth, Chief Operating Officer of TOHS. “Our storage system could be used today in cars and trucks that operate with either internal combustion engines or fuel cells, it could also be used as an alternative to batteries for power back-up systems, as a fuel alternative for on-site generation, and it could be installed in just about any end-use application that today uses traditional hydrocarbon fuels.”
TOHS’ solid hydrogen storage system works by absorbing hydrogen in a metal powder, with the hydrogen and powder bonding at the atomic level upon contact. Removing heat drives this absorption process. Hydrogen is released out of the metal powder and into the vehicle’s fuel system by adding heat to reverse the chemical reaction. Those who have driven the modified hydrogen hybrid vehicle say the system works as seamlessly as the more conventional gasoline tank and fuel pump systems found in today’s automobiles.
This converted hydrogen hybrid has led to a follow-on South Coast AQMD program that will add five more hybrid sedans modified to run on hydrogen stored in TOHS’ solid hydrogen storage medium by next spring.
In an environment where 5,000 psi gaseous hydrogen storage provides insufficient driving range and 10,000 psi systems are being developed, the TOHS solid hydrogen storage system offers the option of storing hydrogen at a low 250 psi. Refuelling, which occurs at the relatively low pressure of 1,500 psi, takes under 10 minutes. In the future, when used with hybrids, this low- pressure, solid hydrogen storage technology has the potential to deliver the same kind of range, driving experience, and refuelling convenience expected of the vehicles we drive today.
Metal-hydride hydrogen storage is not new – Mazda developed a similar system in the early 90s.