3.3.3 Hydrogen Production
On our planet hydrogen exists mainly as part of other compounds and has to be extracted from them; such as water, fossil fuels, natural gas and coal. It is therefore a manufactured fuel.
In 2006 extracting hydrogen consumed about 60% more energy than the resulting hydrogen provided.
Two of the most common ways of producing hydrogen are by steam reforming and electrolysis.
Steam reforming, mainly from natural gas, is currently the most cost effective and hence the most popular method.
Electrolysis, which extracts hydrogen from water, is currently a much more expensive process.
For every one litre of petrol about four times the amount of liquid hydrogen is required to obtain the same amount of energy.
To store liquid hydrogen at between minus 259.34 and minus 252.87 degrees C it must be kept in a pressurised and thermally insulated container.
Due to the very low temperatures involved liquid hydrogen will slowly evaporate from its container.
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