White hydrogen gas in Canada is accumulating instinctively in some of the oldest known rocks on Earth. For the first time, geochemists from the University of Toronto as well as the University of Ottawa determined its presence, mapped its level of concentration and monitored its long-term accumulation, providing novel insights into this form of natural, or white, hydrogen.
The results allow for an evaluation of the economic viability of this growing energy source and suggest an innovative strategy to hydrogen discovery that could speed up greenhouse gas emissions reductions and broaden hydrogen’s contribution to the clean energy transition.
A study that has been published in the Proceedings of the National Academy of Sciences documents measurements of hydrogen observed directly discharging from the enormous, billion-year-old rocks of the Canadian Shield. The researchers used data from an active mine near Timmins, Ontario, and found that the holes at the site emit a typical 0.008 tonnes of hydrogen every year, which is about 8 kilograms, or the weight of an average-sized car battery, and can do so for 10 years or even more.
When scaled to the site’s almost 15,000 boreholes, this translates to an overall discharge of over 140 tonnes of hydrogen every year. Such discharges could generate 4.7 million kilowatts of energy per year at one site, which, by the way, is sufficient to power the yearly energy needs of more than 400 households.
According to University Professor Barbara Sherwood Lollar in the Department of Earth Sciences in the Faculty of Arts & Science at the University of Toronto and also the lead author of the study, “The data from this study suggests there are critical untapped opportunities to access a domestic source of cost-effective energy produced from the rocks beneath our feet. “What’s more, this provides a ‘made in Canada’ resource that might be able to support local and regional industry hubs and reduce their dependence on importing hydrocarbon-based fuels.”
Today, the global hydrogen economy is a $135 billion industry. Its major uses involve methanol and steel production. The single largest usage of hydrogen is fertilizer production, a basic building block of agriculture and therefore critically linked to global food security. Hydrogen used in these ways is generated now by energy-intensive industrial processes that typically convert hydrocarbons present in fossil fuels like petroleum, natural gas and coal, whilst releasing carbon monoxide as well as CO2 in the process. Even hydrogen produced from renewable energy sources, which is called green hydrogen is energy-intensive, expensive to produce and needs to be transported and stored over long distances.
Thus far, white hydrogen gas in Canada being an energy and manufacturing source has mostly flown beneath the radar, studied primarily by microbiologists who want to know more about the subsurface biosphere and use it to guide astrobiology and space exploration. Until now, the possible contribution of natural hydrogen in Earth’s crust to the present-day global economy has been mostly speculation, determined by models and theoretically accessible amounts, as opposed to measured data. The U of T-led study is the initial one to record large amounts of hydrogen and, most significantly, sustained discharges for years.
Says Sherwood Lollar, “Natural hydrogen is produced over time through underground chemical reactions between rocks and the groundwaters in those rocks. Canada is blessed that vast amounts of its territories, especially on the Canadian Shield, contain the right rocks and minerals to create this natural hydrogen.”
Canada could as well be a supplier of a substitute to industrially produced hydrogen, with natural hydrogen offering cheaper, cleaner forms of the resource minus a requirement for hydrocarbons, researchers say. Then, this novel hydrogen resource development approach could be exported to other countries around the world where hydrogen-producing rocks, likewise, are abundant. They also point out that natural hydrogen exists in the greatest abundance in the same geological environments that have historically been the primary focus of Canada’s mining industry, like Northern Ontario and Quebec, as well as Nunavut along with the Northwest Territories.
According to the study’s co-author and an assistant professor in the Department of Earth and Environmental Sciences at the University of Ottawa, Oliver Warr, “The common link is the rock. Natural hydrogen is produced in the same rocks where Canada’s nickel, copper and diamond deposits are found and that are currently under exploration for critical minerals such as lithium, helium, chromium and cobalt. The co-location of mining resources and hydrogen production and use mitigates the need for long transportation routes to market, for hydrogen storage and major hydrogen infrastructure development.”
This untapped resource could lower costs as well as carbon footprints when it comes to mines in Canada and serve as a means of local clean energy for northern communities, the authors say. A model like this of resource development could not only reduce carbon emissions for the mining industries but could also make a significant contribution to reducing the high price of getting fuel to northern communities.
Sherwood Lollar remarks that “There is a global race to increase hydrogen availability in order to decarbonize and reduce the costs of the existing hydrogen economy. We now have a better understanding of the economic viability of this resource that can be mapped to hydrogen deposits around the world that are both already known and yet to be discovered.”