In the battle to reduce greenhouse gas emissions and delay oil reserve depletion, hydrogen is seen by some as the answer to all our problems. Others point out that it is really just a storage medium and that although a vehicle running on hydrogen does not emit any pollution, the power station that produced the electricity to split the hydrogen from water certainly does. Similarly, if hydrogen is produced directly from oil or coal, the pollution is merely shifted elsewhere.
However, it seems that as a storage medium, hydrogen has many advantages over batteries and as fuel cells become much cheaper as they are improved and mass-produced, hydrogen will become an important way to replace fossil fuels with renewable power. As an example, wind turbines do not stop producing electricity during the night when it is not really needed but the electricity could be used to produce hydrogen by passing a current through water splitting it into hydrogen and oxygen. The fuel cell in a vehicle or any other application, does the opposite by joining the hydrogen with oxygen to make electricity and water.
It will be possible in the future to extract hydrogen directly from biomass and in that way we will be able to convert the energy from the sun in to an easily used form.
At some time in the future we are going to have to rely on the abundant energy coming from the sun instead of the solar energy stored in fossil fuels and hydrogen will surely have a large part to play.
Unfortunately, unless we replace present taxes with a carbon tax, progress to a hydrogen economy will be too slow to save us from the disaster that will happen if we continue to increase our burning of fossil fuels.