In the rocky soil of Lorraine, a former mining region near the Franco-German border, scientists recently guided a small probe into a borehole located 800 meters from the earth’s crust.
The foam in the water table below was an exciting discovery: champagne-sized bubbles that signaled a potentially gigantic cache of so-called white hydrogen, one of nature’s cleanest fuels.
“Hydrogen is magic: when you burn it, you release water, so there are no carbon emissions that warm the planet,” said one of the scientists, lead researcher Jacques Pironon. and professor at the University of Lorraine. “We believe we have discovered one of the largest natural hydrogen deposits in the world.”
The discovery by Mr. Pironon and another scientist, Philippe de Donato, both members of the respected French National Center for Scientific Research, caused a sensation in France, where the government has pledged to become a European leader in the area of clean hydrogen.
Many questions remain about the discovery, including its exact size and how best to extract the gas. But it added to a series of clues elsewhere in the world that a holy grail of clean energy could be hidden underground.
Governments and businesses around the world are banking on hydrogen as a cornerstone in the fight against climate change. A multibillion-dollar industry, backed by billions more in subsidies and private investment, has emerged to support hydrogen manufacturing, which in theory could replace fossil fuels to power factories, trucks, ships and planes, potentially removing about half of all these fuels. emissions that contribute to global warming.
But commercial hydrogen production involves splitting water into hydrogen and oxygen, an activity that requires energy. If fossil fuels are used, the process results in greenhouse gas emissions, and the result is called gray hydrogen. Harnessing renewable electricity from wind turbines and solar panels to produce so-called green hydrogen is cleaner but more expensive.
Natural hydrogen, also called white hydrogen because of its purity, could be a game-changer, scientists say, because it is a potential source of clean energy continuously generated by Earth. Hydrogen reservoirs form when heated water encounters iron-rich rocks. Only a small fraction of these deposits could provide enough clean energy for hundreds of years, according to the U.S. Geological Survey.
“If they verify this discovery, then it is very important and would have a big impact on society,” Geoffrey Ellis, a geochemist at the US Geological Survey and a world expert on hydrogen, said of the French discovery. “There are many other places around the world where similar discoveries could also be made, and people are interested in it because it could really have an impact.”
In Lorraine, scientists said their tests suggested 46 million to 260 million tons of natural hydrogen could be hiding beneath coal mines, abandoned in the 1970s when France moved to nuclear power. For comparison, around 70 million tonnes of hydrogen are produced commercially each year worldwide.
Natural reserves of hydrogen have recently been detected in parts of the United States, Australia, Africa, Russia and elsewhere in Europe. It’s not uncommon to find hydrogen while drilling for gas or oil, but in the past, companies have ignored these discoveries due to low demand.
Researchers didn’t give much credence to white hydrogen until a chance discovery in Bourakébougou, a small village in Mali, in 1987, when a worker accidentally set fire to a water well by lighting a cigarette on it. The well was found to contain natural hydrogen and it is now used to power shops and homes after a local entrepreneur hired an oil company to exploit the gas.
“People weren’t looking for natural hydrogen for years and years because everyone was focused on oil and gas drilling,” said Julien Moulin, president of Française De l’Énergie, a clean energy company. who works with Mr. Pironon and Mr. de Donato to test and develop white hydrogen projects. “But I feel like we’re at the start of a new dynamic,” he said.
Française De l’Énergie’s main activity is to capture methane from coal deposits and convert it into clean energy for the region’s industries. With the discovery of hydrogen, the company will step up efforts to explore and extract it, Moulin said.
“You have the cake; now the question is how to eat it? ” he said. “You need to create the tools necessary to develop this resource, and that will be the work of the next few years. »
The efforts in Lorraine reflect the wider enthusiasm for natural hydrogen in the clean fuels industry. The growing awareness that Earth is its own hydrogen factory has sparked a mini gold rush among researchers and energy start-ups eager to make a discovery.
In Australia, Gold Hydrogen, an independent energy company, is searching for natural hydrogen near Adelaide after discovering historical records from two oil wells drilled in the 1930s that showed large quantities of high purity hydrogen in the region. Bill Gates is one of the American investors who financed Koloma, a Colorado company which is searching for hydrogen in a huge geological fault in the Midwest. In Europe, small energy companies from Spain, Switzerland, the Nordic countries and elsewhere all roam the earth’s crust.
It remains to be seen whether white hydrogen will live up to the hype. Discoveries so far range from potentially huge finds that can take years to verify, like the one at Lorraine, to small or extremely deep accumulations that might not be economically viable to mine, Mr. Ellis said. Questions remain about whether it is an unlimited source of clean fuel. The big oil companies, like the French TotalEnergies, have not invested and seem to be waiting to see how things develop.
Then there’s the cost. Although the United States and Europe have set aside billions to subsidize the development of green hydrogen using renewable energy, none of these funds are used to encourage the production of white hydrogen.
And white hydrogen producers must monitor the final price of their gas. Although green hydrogen costs about $5 per kilogram to produce – more than twice as much as gray hydrogen – the U.S. Department of Energy is sponsoring a program to reduce the price of green hydrogen to $1 dollar per kilogram within a decade.
In Spain, a start-up called Helios Aragón is developing a natural hydrogen production project in the Pyrenees that it says can match or beat that price.
“The No. 1 question is what the cost will be,” said Marco Alverà, chief executive of Tree Energy Solutions, or TES, a company that plans to produce and import clean hydrogen to Europe. For natural hydrogen to be competitive, “it depends on many factors, including the pressure the gas is under, the temperature and the type of rock you’re drilling into,” he said.
At the same time, Europe is building a vast network of pipelines that could carry manufactured hydrogen to factories and refueling sites. The hope is that one day white hydrogen can pass through them.
If all goes according to plan in Lorraine, new drilling will begin next year with an advanced probe that will take gas samples up to 1.8 miles underground – deeper than the length of the Golden Gate Bridge – to test the the scale of the hydrogen treasure. , with the aim of extracting natural hydrogen by 2027 or 2028.
Mr. Pironon and Mr. de Donato have high hopes. When they began looking for methane left behind by coal mines, they discovered hydrogen the deeper they went. At 800 meters depth, they found higher concentrations of hydrogen than reported elsewhere in the world, de Donato said.
“We could have a real hydrogen factory hidden under our feet,” he said. “It’s a real source of enthusiasm.”