Energy

What it is

Natural hydrogen is a colourless, odourless and non-toxic gas. It is very light, 14.4 times lighter than the air. Consequently, natural hydrogen alone cannot be found on the Earth since it disperses into the outer space. Researchers say that hydrogen only represents 0.9% of the Earth’s crust components. It can be found in elementary state in volcanic emissions, fumaroles, and oil springs. However it is present combined with other elements in many compounds such as water, mineral substances, hydrocarbons such as oil and methane, coal, animal and vegetal organisms, and organic substances. Therefore, if natural hydrogen is to be found, it will be necessary to consume much energy to extract it from the substances that contain it. This is why hydrogen is not a primary energy source, but an “energy carrier”, i.e. a form of energy that is not naturally available (as the case is with natural gas, oil or coal). In the gaseous state it is a good fuel, albeit less dense than natural gas. When it is burnt, it produces a quantity of heat expressed in Joules per kilogram 2.6 times greater than the energy produced by burning natural gas. Another feature is that it tends to form hydrides, i.e. solid compounds, when it gets in contact with most of elementary metals, thus making them more fragile. If it is cooled at a temperature of –253°C, hydrogen becomes liquid and in that state it does not react chemically with metals. This is the reason why it is difficult, in the gaseous state, to use pipelines to transport it, whereas it is easier to transport it when it is liquid.