Yesterday, the largest industrial plant to ever sucking tons of carbon dioxide from the atmosphere was opened in southwest Iceland. These plants have been praised by global leaders and large corporations, including Microsoft, who are trying to eradicate their legacy of greenhouse gas emissions.
This particular operation is ideal for testing the new technology. Climeworks in Switzerland built the new plant. It is powered by renewable energy generated from nearby geothermal power plants. Climeworks plans to store the CO2 captured in basalt rock formations located just three kilometers away from the geothermal power plant. This storage plan will likely eliminate the need to build controversial new carbon dioxide pipes.
It will be an interesting test case, according to David Morrow (director of research at American University's Institute for Carbon Removal Law and Policy). It's a small step, but it is a significant one in the grand scheme of things.
One baby step in the grand scheme of things
The Climeworks' new direct air capture plant Orca, which is the Icelandic name for energy, can draw down 4,000 tonnes of carbon dioxide each year. This is about the amount that 790 passenger cars could produce in a single year. It's not an insignificant amount, even though it's the largest of its kind anywhere in the world.
This new plant is surprising compact. Imagine a shipping container with twelve huge fans that opens on one side. The eight containers that make up the plant are stacked one by two.
Climeworks employs a method known as solid direct air capture to capture CO2. This is how it works: The fans take in the air. The carbon dioxide is trapped in the air as it passes through a solid sorbent filter. Climeworks would not discuss the operation of its filters in an interview with The Verge. It uses a mildly acidic base to attract CO2. Once the filter has become saturated, it is time to move on to the next step. The filter is heated to around 100° Celsius (212° Fahrenheit) and the carbon dioxide trapped in it is released.
After the CO2 is separated from the air, it travels through pipes to a nearby building where it can then be stored permanently. It is then mixed with lots of water, approximately 27 tons for every ton carbon dioxide. The slurry travels only a few hundred metres (about a quarter mile) before being injected into the ground. Carbonate minerals are formed when carbonated water reacts to basaltic rocks. What was once sparkling water is now solid rock after two years.
Climeworks and Carbfix have partnered to secure the CO2 captured in Iceland's basalt rock formations. Although the pilot project was already completed by both companies, Orca is the first commercial-scale operation.
Climeworks and two other large-scale commercial-scale direct-air capture plants convert carbon dioxide into fertilizer or fizzy drinks. The CO2 is released back into the atmosphere very quickly. Carbfix believes that the CO2 trapped by Orca can be safely stored in rock for thousands of years. Basaltic rocks are common all over the globe, but Iceland with its younger basalt is more suitable for carbon dioxide storage. Because it is porous, fresh basalt provides more carbon to store.
The operation avoids one potential problem with carbon removal by placing Orca at the same location where the CO2 will be kept. This is because it does not require the creation of a new network to transport carbon dioxide. There are already pipelines that transport CO2 to the ground so it can be used to extract oil reserves. This is called enhanced oil recovery. One such pipeline burst in Mississippi last year, causing severe injuries to residents of a predominantly black community.
Another advantage to the plants' location is its proximity with a geothermal power plant. This provides the plant with constant heat and renewable energy. This, combined with Climeworks solid air capture process, gives Orca an advantage over its competitors. In Texas and Scotland, larger direct air capture plants will be available in the coming years. However, these plants use a different process and require a lot more heat and energy. They will likely use a mixture of natural gas and renewable energy.
You want to reduce the amount of CO2 you emit from fossil fuels if your business is to remove it. Christoph Beuttler is Climeworks' head of climate policy.
Another obstacle is cost.
The cost of direct air capture is another obstacle that prevents it from becoming large enough to reduce global greenhouse gas emissions. Climeworks is both an investor as well as a customer of Microsoft, who pledged last year that it would capture all its historical emissions by 2050. Climeworks offers a $600 per ton option for Microsoft and other companies to purchase CO2 captured from them. This will offset a ton their own pollution. Microsoft alone was responsible for 11,164,000 metric tons carbon dioxide in its 2020 fiscal year. Multiply this by $600 and Microsoft will be faced with a bill for nearly $6.7 billion just for one year of pollution.
It might not be financially feasible to address climate change in this manner unless the price of carbon can drop significantly. Some environmentalists are concerned that focusing on this technology may lead to the loss of resources for other climate solutions and increase pressure on companies to stop burning fossil fuels.
Morrow states that people are concerned that companies that make net-zero pledges won't just use direct air capture to reduce emissions. It seems unlikely that direct aircapture would be cheap enough to make this a practical option.
While direct air capture may play a limited role in trapping some of the planet's warming emissions, it is not a replacement for deep cuts in fossil fuel pollution. Morrow states that it is a supplement that can be used to help reduce climate change. It cannot replace cutting emissions.
