Direct air capture for a renewable grid

This new technology could make carbon capture more economically feasible

Spotted: Direct air capture (DAC) could play a big role in trapping emissions and combatting climate change, but existing technologies are often too expensive to scale. One sticking point has been that DAC requires heat to release CO2 from the carbon-capturing sorbents, so it can then be stored elsewhere. Startup Phlair, however, has a cost-friendly alternative.

Instead of heating the sorbent, Phlair’s device uses an acid to free the captured CO2. A basic (high pH) solvent absorbs CO2 from the air as it moves through the air contractor, and the CO2-saturated solvent moves into a tank, where acid (low pH) is added. The rapid change in pH causes a chemical reaction that releases the CO2, which can then be stored. The solvent is then regenerated and reused.

To produce the acid and base used in the process, Phlair has developed a device, which it calls a Hydrolyzer, that uses elements from both membrane-based electrolysers and membrane-based fuel cells. Because the electrochemical process is low-energy – unlike heat-reliant DAC systems – it can be completely powered by intermittent renewable sources and works 24/7.

Currently, capturing a metric tonne of carbon dioxide costs between $600 and $1,000, but according to Phlair, its technology could eventually reduce the cost to around $100. This means it could be a much more practical and accessible solution for large-scale carbon removal.

Phlair will shortly be deploying a pilot project that the company claims can capture around 10 metric tonnes of carbon a year, with a 260-metric-tonne plant scheduled to come online in late 2025. To support completion of the larger plant, Phlair has recently raised a €12 million seed round and been awarded a €2.5 million grant from the EU’s EIC Accelerator.

In addition, the company has already started delivering carbon to make a cement additive, selling carbon credits, and is also working with Deep Sky – a carbon removal project developer in Canada to store carbon.

Written By: Lisa Magloff