Deep beneath some of the oldest rocks on Earth, scientists have discovered a surprising source of clean energy slowly building up underground: natural hydrogen gas.
Researchers from University of Toronto and University of Ottawa have, for the first time, directly measured hydrogen escaping from ancient rocks in the Canadian Shield, a massive geologic region that stretches across much of Canada.
Their findings suggest that this naturally occurring “white hydrogen” could one day become an important new source of clean energy.
The study, published in the Proceedings of the National Academy of Sciences, focused on an operating mine near Timmins, Ontario. Scientists measured hydrogen gas flowing out of boreholes drilled into billion-year-old rocks deep underground.
The results were remarkable. Each borehole released about 8 kilograms of hydrogen per year on average, roughly equal to the weight of a standard car battery.
Even more importantly, the gas continued flowing steadily for more than a decade.
When researchers calculated the total output from nearly 15,000 boreholes at the site, they estimated that more than 140 metric tons of hydrogen could be released every year.
That amount of hydrogen could generate around 4.7 million kilowatts of energy annually, enough to supply energy for more than 400 households.
Lead researcher Barbara Sherwood Lollar says the findings reveal a major untapped energy opportunity hidden beneath Canada’s surface. She explained that the hydrogen is naturally created through chemical reactions between underground rocks and groundwater over extremely long periods of time.
Unlike most hydrogen used today, this natural hydrogen does not need to be manufactured using fossil fuels or large amounts of electricity. Currently, most industrial hydrogen is produced from natural gas, coal, or petroleum, processes that release carbon dioxide and contribute to climate change. Even “green hydrogen,” which is made using renewable energy, can still be expensive and energy intensive to produce and transport.
Natural hydrogen could offer a simpler and potentially cheaper alternative.
Canada may be especially well positioned to benefit because the Canadian Shield contains the right types of rocks and minerals for producing hydrogen naturally. These same geologic regions are already famous for mining valuable resources such as nickel, copper, diamonds, lithium, cobalt, and chromium.
Co-author Oliver Warr explained that this overlap could create major advantages. Mines and industrial operations could potentially use hydrogen produced directly at the site, reducing the need for expensive transportation pipelines, storage systems, or imported fuels.
The discovery could also have important benefits for remote northern communities, many of which rely on costly transported diesel fuel. Local natural hydrogen supplies could help reduce fuel costs while lowering greenhouse gas emissions.
Until now, natural hydrogen was mostly studied by scientists interested in underground microbes or even the possibility of life on other planets. Its potential as a real-world energy source remained largely theoretical because few long-term measurements existed.
This new study changes that. By showing that hydrogen can continuously flow from underground rocks for years, the researchers believe they now have evidence that natural hydrogen may become a practical clean energy resource not only in Canada, but around the world.
As countries search for ways to reduce carbon emissions and expand clean energy, the ancient rocks beneath Canada may hold part of the answer.
