When two scientists went looking for fossil fuels beneath the ground of northeastern France, they did not expect to discover something which could supercharge the effort to tackle the climate crisis.
Jacques Pironon and Phillipe De Donato, both directors of research at France’s National Centre of Scientific Research, were assessing the amount of methane in the subsoils of the Lorraine mining basin using a “world first” specialized probe, able to analyze gases dissolved in the water of rock formations deep underground.
A couple of hundred meters down, the probe found low concentrations of hydrogen. “This was not a real surprise for us,” Pironon told CNN; it’s common to find small amounts near the surface of a borehole. But as the probe went deeper, the concentration ticked up. At 1,100 meters down it was 14%, at 1,250 meters it was 20%.
This was surprising, Pironon said. It indicated the presence of a large reservoir of hydrogen beneath. They ran calculations and estimated the deposit could contain between 6 million and 250 million metric tons of hydrogen.
That could make it one of the largest deposits of “white hydrogen” ever discovered, Pironon said. The find has helped fuel an already feverish interest in the gas.
White hydrogen – also referred to as “natural,” “gold” or “geologic” hydrogen – is naturally produced or present in the Earth’s crust and has become something of a climate holy grail.
Hydrogen produces only water when burned, making it very attractive as a potential clean energy source for industries like aviation, shipping and steel-making that need so much energy it’s almost impossible to meet through renewables such as solar and wind.
But while hydrogen is the most abundant element in the universe, it generally exists combined with other molecules. Currently, commercial hydrogen is produced in an energy-intensive process almost entirely powered by fossil fuels.
A rainbow of colors is used as a shorthand for the different types of hydrogen. “Gray” is made from methane gas and “brown” from coal. “Blue” hydrogen is the same as gray, but the planet-heating pollution produced is captured before it goes into the atmosphere.
The most promising from a climate perspective is “green” hydrogen, made using renewable energy to split water. Yet production remains small scale and expensive.
That’s why interest in white hydrogen, a potentially abundant, untapped source of clean-burning energy, has ratcheted up over the last few years.
