As the world reaches for cleaner energy, hydrogen has long been viewed with a lot of hope.
Often called the fuel of the future, the gas can be used to generate electricity and power vehicles. It produces water — not carbon — when burned.
But among its challenges is the economics of producing the gas in a large-scale and environmentally friendly way. One of the least expensive methods for doing so, for example, using methane, has drawn scrutiny for its carbon emissions.
Now, engineers in Alberta believe they could have an answer — a method capable of extracting hydrogen from underground resources like oilsands deposits while leaving the carbon emissions it produces below the surface.
The team turned heads with their work this summer at the Goldschmidt Geochemistry Conference in Barcelona, making headlines from Britain to Japan.
Hydrogen can be found in many different organic compounds, including hydrocarbons like oil and gas.
One of the most common ways of producing hydrogen from natural gas is called steam-methane reforming, which uses methane and very hot steam under pressure to create a chemical reaction freeing the hydrogen and capturing it in special filters. The waste emissions are carbon dioxide and carbon monoxide.
“That’s been an industrial technology for over 80 [years],” said Grant Strem, CEO of Proton Technologies, the private company commercializing the new process for creating hydrogen.
“What we’re doing is very similar, but the big difference is, we’re using the ground as a reaction vessel, so our capital cost is a lot lower, and instead of buying natural gas to fuel it, we use the unswept oil in the reservoir as our fuel.”
How the process works
Through lab work and small-scale field testing, the researchers say they found injecting oxygen into the fields raises the temperature and creates a reaction that frees the hydrogen.
“You can envision that the reservoir is simply a hot, bubbling mix of oil, which some fraction of it is now combusting,” said professor Ian Gates, from his lab at the University of Calgary’s Schulich School of Engineering.
“And as it is doing so, it simply keeps producing more and more hydrogen as a consequence of its reactions.”
Gates said palladium alloy filters then allow the hydrogen to come to surface while filtering out the other gases, like carbon dioxide or hydrogen sulfide, which stay below ground.
Conceptually, Gates said, the oil in the reservoir could later be produced.
But the expectation is the process can draw up “huge” quantities of hydrogen relatively inexpensively.
And Canada would be able to tap its resources.
“There’s a lot of work toward renewables, hydro and all those other things, but you still have a huge amount of assets, chemical energy, stored in oil,” Gates said.
“What this is about is how do we make use of oil reservoirs — or even gas reservoirs — and get pure, clean energy out of it.”
Gates said after proving the concept in the field last year, they will soon begin testing to see how it works on a larger scale. A semi-commercial pilot project is in the works for next year.
Proton Technologies is working with an engineering firm to design a scaled-up version of their demonstration facility at its site in Kerrobert, Sask.
Now, the challenge will be to see how the process works in the field with all of the complexities of a reservoir.
“Does [the hydrogen] really transport as effectively as you predicted in your models, as you’ve estimated from the lab?” he said. “Everything so far is supportive. Yes, we should be able to access it, but we do need to verify that.”
Reservoirs that are open to the surface or very shallow would not likely be good candidates for such a system, he said.
Field testing needed
After the team’s work was presented at the Goldschmidt conference in Barcelona last month, some experts responded with cautious optimism, emphasizing the need for extensive field testing of the technology to assess how well it could work on an industrial scale and over time.
In Canada, Warren Mabee, the director of the Queen’s Institute for Energy and Environmental Policy, said having a large source of hydrogen that’s relatively easy to access would be an important step toward a cleaner energy future.
“There are some technologies that can use hydrogen really well,” Mabee told CBC News.
“It’s very, very clean as long as there’s not a lot of greenhouse gas associated with producing it, which, in this case, it sounds like there isn’t. Which is a wonderful technology, if we’ve gotten to that point.”
Significant research is being done on developing new ways of producing hydrogen, including microbes and solar technologies, among others.
China, Japan and South Korea have big plans to put millions of hydrogen-powered vehicles on their roads in the coming decade.
Hydrogen has had false starts
Hydrogen was also a key topic of conversation during a July meeting hosted by the International Energy Agency. The Paris-based body, which advises on energy policy to its 30 member states, said hydrogen was enjoying “unprecedented momentum,” offering ways to decarbonize a range of sectors, including long-haul transportation.
“But it has experienced false starts in the past and still faces big challenges to scale up infrastructure and bring down costs,” the IEA said in a release.
A lack of refueling stations for hydrogen fuel cell vehicles is often pointed to as a major barrier to the technology taking off.
The delivery process for the hydrogen — including pipelines, storage facilities, compressors and trucks — is also a work in progress when it comes to widespread consumer use.
Gates and Strem hope they can do their part to move things forward.
“I’m very motivated by the idea of taking these [hydrocarbon] resources, which are of incredible value to Canada, and pivoting their use toward hydrogen production and ultra-clean energy outcomes,” Gates said.
“In my view, this is something that’s quite exciting.”