Earth may contain large reserves of pure hydrogen

Believe it or not, drilling for a certain type of gas could create a new world of clean energy.

Thousands of billions of tons of hydrogen gas could be hidden deep underground. This nature reserve, known as geohydrogen, could be a carbon-free energy source.

Pure hydrogen is so attractive that Microsoft founder Bill Gates and tech giant Amazon are among the financiers of startup Coloma, which believes it can tap these reserves.

Oil and gas giants BP and Chevron have also joined a consortium to study geological hydrogen.

“The vast majority of hydrogen is likely present in sediments that are too deep, too far offshore, or too small to be extracted economically,” said Geoffrey Ellis, a geologist with the US Geological Survey. “But if a small fraction of that amount could be extracted, it would be a significant resource.”

Hydrogen produces no carbon dioxide emissions when burned, but its production costs a lot of energy and money and is associated with carbon dioxide emissions. However, it is a key pillar of President Joe Biden's clean energy strategy, which is pumping $7 billion into seven hydrogen centers in the United States.

Getting hydrogen from natural reservoirs would be much cleaner, but it would have to be worth the digging.

Geological hydrogen arouses interest

It's a relatively new possibility. Until about 12 years ago, scientists didn't think it was possible for significant amounts of hydrogen to accumulate underground, says geologist Ellis. At the USGS, he is involved in mapping the world's potential underground hydrogen reserves.

In 2011, an oil and gas company investigated a mine in Mali that exploded and discovered it was filled with hydrogen gas.

Hydrogen is formed deep within the Earth when water reacts with iron-rich rocks. In the United States, two long pieces of this rock are a promising place to look for hydrogen reserves. This is already being worked on.

One stretch runs from Kansas to Ontario and then to Michigan. The other stretch is offshore and extends from New Jersey to Georgia, Ellis said. The USGS began exploring these reserves in 2021 and has already drilled several wells. More drilling is scheduled to take place this year.

Investigations are also underway in France and Australia, and active searches are underway in Brazil and Colombia. In February, researchers reported the discovery of a hydrogen tank in a mine in Albania.

It is still unclear how much geological hydrogen exists and how much it will cost to extract it.

However, this energy source will face some of the same challenges as hydrogen extracted from natural gas. There may not be enough infrastructure to transport pure hydrogen efficiently.

The extraction process can also release hydrogen into the atmosphere and react with other elements, causing the atmosphere to retain more heat. This could negate the climate advantage of hydrogen over fossil fuels.

“No one has all the answers yet,” Coloma CEO Pete Johnson recently said at a US Senate hearing. “But the early data looks promising and I think geological hydrogen could play a very big role.”

Read also: Why we don't have nuclear fusion power plants yet and what it takes to generate untold amounts of clean energy