World's first negative-emission power plant

For the first time in the world, an energy generation installation captures CO2, converts it into a solid mineral and thus allows its permanent storage and prevents its release into the atmosphere. This pioneering solution, which has just started its test phase at Hellisheidi geothermal power plant in Iceland, aspires to contribute to the objective reached at the Paris Climate Summit of limiting the rise in temperatures to a maximum of two degrees by the end of the century.

According to the Swiss company Climeworks, which participates in the project, scientists have warned that this goal would not be possible without solutions allowing the elimination of carbon. Hence, and its radical novelty, the attention aroused by this technology which is already today fixing 60% of the gases generated in the Icelandic plant in the form of minerals in the production of electricity and hot water.

The immediate objective, in addition to operating the Hellisheidi plant without emissions into the atmosphere, is to prove that this initiative of direct capture of carbon dioxide and its geological storage is an alternative. “Safe, economically viable and scalable”, according to Climeworks.

The tests began with the installation at the Hellisheidi factory of a DAC module (Direct air capture, in Spanish, direct air capture), which allows the mineralization of CO2 on an industrial scale. This is achieved through the following process. First, technology captures carbon dioxide and hydrogen sulfide of the environment itself. Diluted in water, the gases are sent 700 meters underground. At this stage, and thanks to the reaction produced by the basaltic rocks of the place, a solid mineral is formed which allows the permanent storage of these gases.

This process, made possible by a filter patented by the Swiss company, emulates mineralization that would occur naturally over the centuries, although it speeds it up significantly. “We have proven that we can permanently convert greenhouse gases into rocks by mimicking natural processes, but in a way that happens in less than two years.”, says Edda Sif Aradóttir, project manager at Reykjavik Energy.

Called CarbFix2, this work funded by the European Union under the Horizon 2020 program it started ten years ago. Today, a decisive step has been taken in this technology, which still has several challenges for its expansion, including its economic viability. Currently, extracting a ton of CO2 costs around $ 600. In addition, for the moment, the power of this plant is limited, since the annual capacity should be 900 tons.

However, the companies involved in this project are optimistic. The potential for scaling our technology in combination with CO2 storage is huge; not only in Iceland, but in many places with similar rock formations “; says Christoph Gebald, Founder and Director of Climeworks, a company committed to continuing to work with a clear goal: to facilitate the capture of 1% of global emissions by 2025.