Hot Spot
Iceland sits on top of a geological hot spot that’s pushing up from the Atlantic floor, so everywhere you go, there’s hot water and steam right beneath your feet. The ground even seethes with steam, about a half hour drive east of Reykjavik, there’s a bizarre, thick fog pouring out of the pebbly earth.
Cleverly, they’ve used this strange feature to their advantage. As Edda Aradóttir, from Reykjavik Energy, which runs the Hellisheiði power plant in this part of Iceland, said, “More or less, all our electricity comes from geothermal.”
Geothermal steam spins the plant’s generators. The thing is, it’s green energy but it’s not completely clean because the steam contains small amounts of the greenhouse gas carbon dioxide. Reykjavik Energy decided to figure out a way to keep that carbon dioxide out of the atmosphere. “Whatever we can do to make geothermal even greener, we want to work on that,” Aradóttir said.
Greener Geothermal
That’s how they came up with CarbFix, the process that captures carbon dioxide from big, single sources like power plants and locks it deep underground; not as a gas that might escape again, but as a mineral bound to the basalt rock below Iceland. They essentially figured out how to turn air into stone.
Reykjavik Energy has led the CarbFix team in the development of a secure, cost-effective, and environmentally benign process and technology for permanent CO2 (Carbon Dioxide) mineral storage in the subsurface. Their new industrial process captures CO2 and other sour gases from emission sources, then permanently stores it as rock underground.
How It Works
The process begins by capturing the steam after it’s spun the turbines. The captured steam gets fed into a tower at the bottom while at the same time cold water gets fed into the tower at the top. The result is water filled with dissolved carbon dioxide.
Next, all that soda water gets pumped up to a mile underground where “it reacts with the rock underneath us to produce new types of stones,” Pétur Már Gíslason explained. This is why Reykjavik Energy calls this project CarbFix, because the carbon is getting fixed into rock.
The Pilot Site
The company wasn’t sure how well it would work when they began over a decade ago. But, the company’s geologist, Sandra Snæbjörnsdóttir, says it’s been successful. The process has been proven to work through a pilot project. The location was a site 3 km southwest of Hellisheiði power plant.
There they were able to demonstrated that over 95% of CO2 captured and injected was turned into rock in the subsurface in less than two years – impressive figuring this was previously thought to take thousands of years. They proved that wrong!
The pilot has been so successful that by the end of 2018, 66,000 tons of sour gases had been captured and injected at Hellisheiði. 2/3rds of which were CO2 and 1/3rd Hydrogen sulfide (H2S). This accounts for over 40% reduction in emissions from the power plant.
This sort of success definitely makes the process attractive, even beyond Iceland, and possibly also in places where electricity comes from burning dirty fossil fuels. For now, however, that is just a theory. Before tackling the challenge of using this technology with fossil fuels they have to finish refining the process and then scale up their efforts.
Promo Strategies
The CarbFix website explains how their team is currently working on the following fronts, facilitating widespread, global application of the CarbFix method:
- Linking the method to direct capture of CO2 from air, allowing for permanent removal of CO2 already emitted to the atmosphere. This work is being done in collaboration with Climeworks under the EU funded CarbFix2 project.
- Exporting the method to new injection sites in Iceland, Germany, Italy and Turkey under the scope of the EU funded GECO project. The field sites consist of varied geology; basalts, gneiss, sedimentary, and volcano-clastic/limestone.
- Further developing the CarbFix method so that it can be used offshore for permanent mineral storage of CO2 in the sub-seafloor.
- Providing consultancy to businesses and industries wanting to apply the CarbFix process to reduce their emissions.
A Piece Of The Puzzle
Even though there’s still a ways to go before this becomes mainstream, it is amazing what they’ve done already – how they has transformed the Hellisheiði power plant into something of a laboratory for other companies working on what’s called carbon capture and storage. And although this is not the save all approach to solve the problem of climate change, it is a good help.
As Snæbjörnsdóttir says, it’s just another tool. “It’s definitely not ‘the solution,’ but it’s one of the solutions that can be used in the fight against climate change. And we will need all the solutions possible for this huge problem to be solved,” she told The World.
