Deep storage

As part of the brand’s ongoing commitment to meeting its own climate targets, Audi is partnering with Zurich-based environmental start-up, Climeworks, which is building the world’s largest direct air capture and storage facility for converting atmospheric CO2 to rock in Iceland. 

The facility will filter 4000 metric tons of carbon dioxide from the air and mineralise it underground – 1000 metric tons of which Climeworks is removing from the atmosphere on behalf of Audi.
The process of direct air capture technology sees carbon dioxide extracted from the ambient air and air free of CO2 is returned to the atmosphere. Climeworks’ new facility in Iceland transports the CO2 filtered out of the air below the Earth’s surface, where natural processes then mineralise it, permanently removing the carbon dioxide from the atmosphere. 

The facility first draws in air and feeds it into the CO2 collector, which contains a selective filter material. This uses a specially developed adsorbent to bind the CO2 in the air and when this filter is saturated with CO2, it is heated to 100 degrees Celsius using waste heat from a nearby geothermal plant to release the CO2 molecules. 

Water from the Hellisheiði power plant then flows through the facility and transports the carbon dioxide some 2000 metres under ground. The CO2 molecules react through natural mineralisation processes with the basalt rock and are converted to carbonates over a period of several years while the water returns to the cycle of the geothermal power plant. 

The facility will operate 24 hours a day, seven days a week, and of the 4000 metric tons it filters from the atmosphere each year, a quarter of that will be credited to Audi – 80,000 trees would be needed to bind this amount naturally.

Iceland is one of several places on Earth offering the ideal conditions for this process. Its volcanic origin makes the country one of the world’s most potent geothermal regions. The particularly high geothermal energy means that the Earth’s heat can be converted to electricity cost-effectively and virtually CO2 neutrally, while the rock in Iceland has the ideal composition for storing large amounts of CO2. 

Audi has set ambitious targets in all areas of the company with the goal of achieving net CO2-neutrality company-wide by 2050. As part of that goal, the brand has been supporting the development of CO2 capturing technology from the Zurich-based environmental start-up Climeworks since 2013, and Audi is also supporting the Swiss start-up with its technological know-how, including the development of new heat exchanger concepts. For now, this high reduction capacity makes for particularly efficient removal of CO2 from the atmosphere, and the
technology can also be scaled up to the megaton-per-year range, exhibiting great potential from the future.