Microsoft just backed a big plan to capture carbon dioxide emissions from a wood-burning power plant. Today, the tech giant announced an agreement with Danish energy company Ørsted to buy credits representing 2.76 million metric tons of carbon dioxide captured at Ørsted’s Asnæs power plant over 11 years.
It is one of the largest deals a company has made to date to reduce carbon dioxide emissions, according to a press release from Ørsted. The move is supposed to help Microsoft meet its goal of becoming carbon negative by 2030, the point at which the company is removing more planet-warming carbon dioxide from the atmosphere than it generates through its operations.
It is one of the largest deals a company has made to date to reduce carbon dioxide emissions.
But the technology to capture carbon dioxide emissions is still in its infancy, and some environmental groups and researchers are skeptical that the strategy Microsoft just helped fund could be an effective way to tackle climate change. Without Microsoft’s support, Ørsted would not have been able to install carbon capture devices at its power plant. “The subsidies from the Danish state and the Microsoft contract were necessary to make this project viable,” says Ørsted. ad says.
With the help of Microsoft, Ørsted was able to win an even longer 20-year contract with the Danish Energy Agency (DEA) to capture CO2 emissions from Asnæs in West Zealand and a second power plant near Copenhagen. After the carbon capture devices are installed, they should be able to capture a total of 430,000 metric tons of CO2 annually by 2026. For comparison, that’s about equivalent how much CO2 a single gas-fired power plant emits in a year.
These power plants, however, burn wood chips and straw, fuels also known as “biomass.” And burning biomass, which can include agricultural waste and other plant materials, as a sustainable energy source is controversial. The EU counts biomass as your largest source of renewable energybut much of the wood that is burned comes from trees felled in forests all over the world. Europe and the southeast US. Ørsted says that the wood chips burned at its Asnæs power station “come from sustainably managed production forests and consist of residues from pruned or bent trees.”
How is burning trees supposed to be good for the environment?
How is burning trees supposed to be good for the environment? After all, wood still releases CO2 when it burns. The argument is that trees or crops used to produce biomass absorb and store CO2 naturally when they are alive. So if you replant the trees or plants, you can potentially have a fuel that is carbon neutral.
Ørsted goes a step further by adding technologies that can filter CO2 from the smokestacks of its power plants, preventing it from escaping into the atmosphere. By doing so, he believes his biomass-burning power plants will become carbon negative. They plan to bury the excess carbon dioxide they capture under the North Sea and sell credits to Microsoft for every ton of CO2. Microsoft can then use those credits to claim that it has written off some of its own greenhouse gas pollution.
If all of that sounds like a tricky balancing act, it is. Previous research has found that burning woody biomass can create more CO2 emissions than are captured. This is because only stack emissions are captured does not realize for all the contamination that could result from the felling of the trees and the transport of the wood. Also, trees or plants can take a long time to mature enough for people to rely on them to extract a significant amount of CO2.
“We think the details are crucial,” says Phillip Goodman, Microsoft’s director of carbon removal portfolio, in an email to the edge. An effective carbon capture project would need to use biomass “harvested from appropriate areas” and account for all its “process” emissions, Goodman says. Microsoft declined to say how much it would pay Ørsted for carbon offset credits for this particular project.
Microsoft has been making some bold bets in climate tech and clean energy technologies of late. Last week, it announced a plan to buy electricity from a forthcoming nuclear fusion power plant, though some experts don’t believe such an advanced power plant could realistically be developed for several more decades. Microsoft also paid a Swiss company called Climeworks to filter CO2 out of the air.
