Construction began in June on a facility on the waterfront at Värtan in Stockholm that will remove 800.000 tons of biogenic CO₂ from the atmosphere annually. This makes the Swedish capital the first city in the world to permanently capture and store biogenic carbon on a large scale.
The facility will be built at Stockholm's Exergi biomass plant, which already burns residual flows from the forestry and paper industries to generate heat and electricity. The CO₂ released is biogenic in nature, meaning it was originally absorbed from the atmosphere by trees and plants. By capturing and storing this CO₂, the greenhouse gas is not re-emitted but rather removed from the air.
This process is called BECCS, which stands for bioenergy with carbon capture and storage. The technology Stockholm is using is based on a hot-potassium-carbonate system. The CO₂ is extracted from the flue gases, liquefied, and transported by ship to storage sites beneath the North Sea, where it ultimately converts into solid minerals in the subsurface.
The construction of the facility will cost the equivalent of over €1,2 billion. Funding will come from various sources. The Swedish government will pay a fee for every ton of CO₂ removed over the next fifteen years. In addition, the project will receive €180 million from the European Innovation Fund. Companies can also pay for negative emission rights, providing an additional source of revenue.
Stockholm Exergi expects the facility to be operational in 2028. Over ten years, the project could capture up to 7 million tons of CO₂ from the air, nearly a fifth of Sweden's annual emissions. The heat released during the capture process will be reused for district heating, maintaining energy efficiency.
Internationally, the project is seen as a significant step toward achieving climate neutrality. It demonstrates that cities, technology, and policy can combine to achieve truly negative emissions. According to the IPCC, large-scale deployment of BECCS is necessary to keep global warming below 1,5 degrees Celsius.
Stockholm thus offers a model for other cities seeking to invest in structural CO₂ removal. Provided sufficient sustainable biomass is available and the infrastructure for offshore storage is in place, the model can be scaled up to other parts of Europe.
Source: Information and image provided by Stockholm Exergi, via the press release on beccs.se
