Deep Sky has inked its latest direct air capture (DAC) partnership with Skyrenu Technologies Inc., a winner of the XPRIZE for Carbon Removal student award.

The Montreal-based carbon removal company will be piloting Sherbrooke, Que.-based Skyrenu’s DAC unit at its Alpha Lab test facility in Quebec.

Skyrenu’s DAC technology employs a solid sorbent and mineralizes carbon dioxide (CO2) in mining waste. It will be validated for use in a proposed Deep Sky carbon removal facility which will be designed to remove 200,000 to 300,000 tonnes of CO2 per year from the atmosphere.

“As we source cutting edge DAC technologies from around the globe, we’re proud to highlight innovators in our own backyard of Quebec,” Damien Steel, Deep Sky CEO, said in a release.

Skyrenu co-founders Gabriel Vézina, CEO, and Martin Brouillette, CTO, spoke to Sustainable Biz Canada about their company, its technology and the Deep Sky partnership.

The birth of Skyrenu

An offshoot from the University of Sherbrooke, Skyrenu is based on student research on carbon removal dating back to 2018.

In 2021, the group submitted its technology to the XPRIZE student award “on a lark,” Brouillette said. There was hardly any hope a team from a medium-sized university in Quebec - competing against more prestigious institutions - would prevail, but a “pleasant shock” arrived.

The university team was one of the winners and received a US$250,000 prize. Emboldened by the recognition, Vézina said it demonstrated the effectiveness of the technology. Skyrenu was subsequently founded to commercialize the DAC technology.

Currently patent-pending, the DAC takes in CO2 from the atmosphere and puts it through a solid sorbent that captures and concentrates the greenhouse gas. The CO2-rich vapour is condensed and exposed to a carbonation reactor that connects to asbestos mine tailings.

The reactor helps trap the CO2 in mine tailings to form carbonates, which are “impervious to any atmospheric conditions including very acidic rain” and are stable for millennia, Brouillette said.

The sorbent is regenerated for re-use, minimizing the waste from the process and cutting down on costs.

A bonus is that the mineralization destroys asbestos fibres, eliminating the health and environmental hazard of mine tailings.

Vézina said Skyrenu stands out for its use of a solid sorbent that is automatically moved around in an energy-efficient system, while Brouillette highlighted how it captures and permanently sequesters CO2 in one system.

Skyrenu has plans to deploy modular units at a commercial scale capable of capturing 1,000 tonnes of CO2 per year. Its initial targets are abandoned asbestos mines in Quebec where 700 megatonnes of CO2 can be locked away in the tailings, according to the company.

Partnering with Deep Sky

The growing profile of Skyrenu resulted in a partnership with Deep Sky. Brouillette said the companies were in contact with each other in 2022 and shared the same cause about the need for carbon capture and sequestration to address climate change.

“We came at this conclusion from an engineering background, they came at this conclusion from their business background,” Brouillette explained.

By the beginning of 2023, Skyrenu and Deep Sky were in talks to partner on a project.

Deep Sky was sold a unit of Skyrenu’s DAC for the pilot, which has the capacity to remove 50 tonnes of CO2 per year. Factors such as carbon removal and energy efficiency will be tested.

The case for the partnership was boosted by the relatively close distance between the two companies, Brouillette said. Vézina pointed to the benefits of hosting a carbon removal project in Quebec because of the province's clean electric grid and geology suited for carbon storage.

Skyrenu is not pursuing fundraising, but is instead seeking projects to scale up its technology in areas in need of mine tailing remediation, Brouillette said. Vézina added the company is exploring applications for industrial waste.