Retrofitting air conditioning units to convert carbon dioxide (CO2) into storable, synthetic fuels could remove substantial amounts of CO2 from the atmosphere according to a Perspective in Nature Communications this week. The preliminary analysis suggests that if this approach was used in the Frankfurt Fair Tower in Germany, 2,000-4,000 tonnes of fuel could be produced per year from CO2 capture.

Negative carbon emission technologies are needed to limit global warming. Although there is public and scientific interest in removing CO2 from the atmosphere, a lack of industrial incentives and political action mean viable removal strategies at the billion-tonne scale needed to curb warming have not been realized.

Geoffrey Ozin, Roland Dittmeyer and colleagues propose retrofitting air conditioners with existing, renewable-powered CO2 reduction technology, to directly convert CO2 and water in the air into storable fuels on-site. Assuming a CO2 concentration in the air of 400 parts per million, the authors estimated CO2 removal rates using air circulation volumes for offices, grocery stores and homes. They found that if this technology were to be implemented, the Frankfurt Fair Tower could remove up to 1.5 tonnes of CO2 per hour and 25,000 grocery stores in Germany could capture a total of around 1,000 tonnes of CO2 per hour. When applied to homes, their analysis suggests that in a building consisting of 5-6 flats, 0.5 kg of CO2 could be captured per hour.

The authors argue that this concept could incentivize individuals to collect ‘synthetic oil’ for their own use, in a similar way to decentralized energy generation from solar panels.

Please note that this press release refers to a Perspective, not a Nature Communications research article. A Perspective is intended to provide a forum for authors to discuss models and ideas from a personal viewpoint. Perspectives are peer reviewed.