Alternative Fuel Sources - Hydrogen and Fuel Cells: Advances in Transportation and Power - page 101

and pressure.
No storage tank technology has all of the ideal characteristics for
commercial applications. It would have to be compact, lightweight, safe,
inexpensive, and easily filled. Compressed gas is well developed in spite
of its drawbacks, liquid hydrogen is usable but not widely considered
practical and hydrides may be a future technique. A 2003 report by the
National Research Council found that compressed hydrogen storage at
5,000 to 10,000 psi would be costly, not only for the storage canisters but
also for the compressors and energy needed for compression at refueling
stations.
Various technologies may be used, according to the application.
Cars, sport utility vehicles, vans, buses, and heavy trucks have different
needs and these needs also vary by application, such as urban fleet trucks
and long-haul fleets. In some vehicles, volume is more important while in
others it may be weight or cost.
Compressed gas is being used in most current demonstration vehi-
cles. But, the path to commercialization of any major new technology is a
long one. In 2003 Toyota recalled some of its hydrogen-powered fuel cell
vehicles when a leak was found in the fuel tank of one of the cars leased to
Japan's Ministry of the Environment. The leak was found when a driver
at the ministry heard a strange noise in the car when he was filling up the
hydrogen tank. The problem was quickly identified and fixed a few weeks
later.
HYDROGEN AND SAFETY ISSUES
It is widely believed that hydrogen is particularly dangerous and
some relate hydrogen energy to the hydrogen bomb. When hydrogen is
used in fuel cells, a simple chemical reaction takes place involving the
transfer of electrons to produce an electric current. A hydrogen bomb re-
quires a high temperature nuclear fusion reaction similar to that which oc-
curs in our sun and other stars.
In 1937 the German airship the Hindenburg contained hydrogen
when it burst into fire in a publicized incident. While 35 people lost their
lives and another 62 survived, the Hindenburg did not explode, it caught
fire. The flames spread quickly and the airship sank to the ground. The fire
started as the airship was venting some of its hydrogen, to get closer to the
ground, during an electrical thunderstorm. The airship was also moored