It could be a great source of clean energy, buried deep underground

In the rocky soil of Lorraine, a former coal mining region near the Franco-German border, scientists on a recent day guided a small probe down a half-mile shaft into the Earth’s crust.

Frothing in the water table below was an exciting find: champagne-sized bubbles indicating a potentially gigantic cache of so-called white hydrogen, one of nature’s cleanest-burning fuels.

“Hydrogen is magic: when you burn it you release water, so there are no carbon emissions to warm the planet,” said one of the scientists, Jacques Pironon, lead researcher 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 Pironon and another scientist, Philippe de Donato, both members of France’s respected National Center for Scientific Research, caused a sensation in France, where the government has vowed to become a European leader in clean hydrogen.

Many questions still remain about the find, including its exact size and the best way to extract the gas. But it has added to a series of clues elsewhere in the world that a holy grail of clean energy may be in the ground for the taking.

Governments and companies around the world have been betting on hydrogen as a cornerstone in the fight against climate change. A multi-trillion-dollar industry, backed by billions more in subsidies and private investment, has emerged to support the manufacturing of hydrogen, which could theoretically replace fossil fuels to power factories, trucks, ships and planes, potentially eliminating around half of all production. emissions that warm the planet.

But producing commercial hydrogen involves splitting water into hydrogen and oxygen, a task that requires energy. If fossil fuels are used, the process generates greenhouse gas emissions and the result is called gray hydrogen. Harnessing renewable electricity from wind turbines and solar panels to produce what is 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 deposits form when heated water meets iron-rich rocks. According to the United States Geological Survey, only a small fraction of these deposits could provide enough clean energy for hundreds of years.

“If they verify this discovery, then it will be very significant and would have a great impact on society,” Geoffrey Ellis, a geochemist at the United States Geological Survey and a world expert on hydrogen, said of the French discovery. “There are many other places around the world where similar findings could also be made, and people are looking at them because they could really have an impact.”

In Lorraine, scientists said their tests suggested that between 46 and 260 million metric tons of natural hydrogen could be lurking beneath coal mines, which were abandoned in the 1970s when France switched to nuclear power. In comparison, about 70 million metric tons of hydrogen are produced commercially throughout the world each year.

Natural reserves of hydrogen have recently been detected in parts of the United States, Australia, Africa, Russia and also other parts of Europe. It is not unusual to find hydrogen when drilling for gas or oil, but in the past companies ignored such discoveries due to low demand.

Researchers didn’t give white hydrogen much credence until it had a chance discovery in Bourakébougou, a small town in Mali, in 1987, when a worker accidentally set fire to a water well by lighting a cigarette over it. The well was found to contain natural hydrogen and is now used to power shops and homes after a local businessman contracted with an oil company. company to take advantage of the gas.

“People hadn’t been looking for natural hydrogen for years and years because everyone was focused on drilling for oil and gas,” said Julien Moulin, president of Française de l’Energie, a clean energy company that is working with Pironon and de Donato to test and develop white hydrogen projects. “But it seems like we’re at the beginning of a new dynamic,” he said.

Française De l’Énergie’s core business has been capturing methane gas from coal seams and converting it into clean energy for the region’s industries. With the discovery of hydrogen, the company will intensify its efforts to explore and extract it, Moulin said.

“You’ve got the cake. Now the question is how do you eat it?” he said. “It is necessary to create the tools to develop this resource, and that will be the work of the coming years.”

The efforts in Lorraine reflect a broader enthusiasm sweeping the clean fuels industry about natural hydrogen. The growing realization that Earth is its own hydrogen factory has sparked a mini-gold rush among researchers and energy startups eager to make a find.

In Australia, gold hydrogen, an independent energy company, is digging for natural hydrogen near Adelaide after unearthing historical documents from two oil wells drilled in the 1930s that showed large quantities of high-purity hydrogen in the area. Bill Gates is among investors in the United States who have provided financing for Koloma, a Colorado company searching for hydrogen in a huge geological rift in the Midwest. In Europe, small energy companies from Spain, Switzerland, the Nordic countries and beyond are scouring the Earth’s crust.

It remains to be seen whether white hydrogen lives up to the hype. So far, finds range from potentially huge finds that may take years to verify, like the one at Lorraine, to small or extremely deep accumulations that may not be economically viable to search for, Ellis said. Questions remain about whether this is an unlimited source of clean fuel. Big oil companies, such as France’s TotalEnergies, have not jumped in to invest and appear to be waiting on the sidelines to see how things develop.

Then there is the cost. Although the United States and Europe have set aside billions to subsidize the development of green hydrogen using renewable energy, none of that money goes to encouraging white hydrogen production.

And white hydrogen producers must monitor the final price of their gas. Although green hydrogen costs about $5 per kilogram to produce (more than double that of gray hydrogen), the U.S. Department of Energy is sponsoring a program to bring the price of green hydrogen to $1 per kilogram within a decade.

In Spain, a start-up called Helios Aragon is developing a natural hydrogen production project in the Pyrenees that it claims will be able to equal or exceed that price.

“The number one question is what the cost will be,” said Marco Alverà, CEO 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 being drilled,” he said.

Meanwhile, Europe is building a great grid of pipelines that could deliver manufactured hydrogen to factories and fuel sites. The hope is that someday white hydrogen can flow through them.

If all goes as planned 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 magnitude of the treasure. of hydrogen. , with the goal of extracting natural hydrogen by 2027 or 2028.

Mr. Pironon and Mr. de Donato have high hopes. When they began searching for methane gas left by coal mines, they discovered hydrogen as they went. At a half-mile depth, they found higher concentrations of hydrogen than had been reported anywhere else in the world, de Donato said.

“We could have a real hydrogen factory hidden under our feet,” he said. “It’s a source of real emotion.”