MONTREAL — A former Deep Sky executive said the company’s method of carbon reduction is too slow and costly to have any significant effect on climate change.

Phil De Luna, who left in July after two years at the company as head of engineering and chief commercial and science officer, told The Logic that Deep Sky’s plan to suck carbon from the atmosphere, a process known as direct air capture, also lacked significant revenue streams to make it economically viable.

Since leaving Deep Sky, De Luna has founded Cura, a greentech startup that is developing technology to remove carbon from the cement curing process. The Vancouver-based firm, which emerged from stealth today, is currently raising a seed round. “I felt that I could probably make a bigger impact on industrial carbon emissions” with Cura, De Luna said.

Co-founded by Hopper co-founder Frederic Lalonde in 2022, Montreal-based Deep Sky brought its first direct air capture test facility online in Alberta in August, and more recently announced plans to build a plant in Manitoba.

Yet the company has faced questions about using direct air capture as a means of atmospheric carbon reduction. The process remains expensive, while Lalonde has been vague about the sources of electrical power needed for the energy-intensive process. “The only revenue-generating model [for direct air capture] is carbon credits, which are a tough sell in today’s environment,” De Luna said. 

Deep Sky spokesperson Brooks Wallace didn’t respond to a request for comment.

De Luna co-founded Cura with CEO Erin Bobicki, COO Sabrina Scott and science advisor Curtis Berlinguette. The company’s proprietary technology uses electricity to remove carbon dioxide from lime, a key material used in cement production—and a major source of the atmosphere warming gas, which accounts for roughly eight per cent of global carbon emissions.

Cura says its technology can be retrofitted to existing cement plants at a cost of $200 million for a 500,000-tonne-per-year system. De Luna said the company plans to build its first test facility in Alberta, and is in negotiations to sell its tech to a large cement producer in the province.

Bobicki said the firm is also looking at building out facilities to produce decarbonized limestone to sell to cement companies at a similar price to the carbon-heavy version. “There’s $4 trillion of sunk assets in the cement industry, so why would you walk away from that if you can decarbonize what’s existing at a lower cost point?” Bobicki said. 

Cura is considering Canadian and European funds as co-leads in its seed round, De Luna said.