Letter: Cars of the future

Sir: Christopher Padley's scepticism regarding hydrogen as a fuel for cars of the future (Letters, 5 January) should not go unchallenged.

In the short to medium term, hybrid vehicles will provide a partial answer to the problems of congestion and pollution. In the longer term hydrogen power must be the answer. At present, safe transportation of this fuel is a problem but there are hopeful signs that research is producing answers.

Metal hydrides which can fix hydrogen are one solution. However, the most promising storage technology is being pioneered by the Northern University at Boston, Massachusetts. The claim is that a nanofibre graphite cartridge can safely store huge amounts of hydrogen at a pressure of 40 atmospheres. The gas is released by gradually reducing the pressure. One cartridge is said to be able to fuel a car for 5,000 miles and a cartridge could be reused up to five times (New Scientist, 21/28 December 1996).

Considerable resource is being channelled into the development of photovoltaic cells. As their efficiency increases and unit cost is reduced, they will be the logical source of electricity to produce hydrogen via electrolysis. Car manufacturers are right to recognise that there are glittering prizes to be won in the race for zero emission cars at all points along the energy chain.

Professor PETER F SMITH

Chairman, Environment and Planning Committee

Royal Institute of British Architects

London W1