Madam, - David Sowby (August 30th) has great faith in hydrogen as the future clean fuel for aircraft. I wouldn't be so sure. Allow me to quote an excerpt on this subject from Chris Goodall's recent book How to Live a Low-carbon Life:
"Other madcap suggestions, such as replacing the entire world aircraft fleet with planes that burn hydrogen, fall down because nobody has yet worked out how to store the gas in a dense enough form to transport in a civil airliner. Hydrogen simply does not carry enough energy for each unit of volume, meaning that the fuel tanks need to be four times the size of those for kerosene.
"As one might imagine, the illustrative drawings make the resulting aircraft look strange and ungainly. But looks apart, a project to build a hydrogen airliner is decades away. . . However, politicians hang on to these remote hopes as a way of avoiding the unthinkable - obliging people to fly less."
- Yours, etc,
ADRIAN KILBANE, Cashel, Achill, Co Mayo.