This Earth Day, we're recognizing a trio of Nova Scotian companies that are vying for the new US$100 million Carbon Removal XPRIZE, slated to be decided in 2025. Halifax’s Planetary Technologies and Reazent have both entered the competition as newcomers, and past winner CarbonCure Technologies is back for a second time.

Last year, Dartmouth-based CarbonCure was one of two companies to split the first prize in the initial Carbon XPRIZE, which had a total prize pot of US$20 million. It was awarded to companies finding commercial uses for carbon that would otherwise be emitted into the atmosphere. Now, the Elon Musk Foundation has renewed the competition — previously funded by Canada's Oil Sands Innovation Alliance, or COSIA, and American power company NRG Energy — and increased the prize pot to US$100 million, which it says is the largest cash prize in history.

CarbonCure and Planetary are also both among 60 finalists out of 1,133 competitors for the US$1 million Milestone Award, which is an interim prize given to 15 companies based on their progress so far. After the Milestone Awards are handed out, the competition will reset and each company will again be treated as being on an equal footing.

“Team CarbonCure knows how to win an XPRIZE,” said CarbonCure President Jennifer Wagner in a Facebook video. “We also know how to scale technologies around the world.”

The stated purpose of the XPRIZE is to incentivize entrepreneurs to work towards a socially desirable goal by offering them a mammoth cash prize. The winners can then use their spoils to further develop their product, while the losers will still have made useful headway on the problem in the meantime.

In the case of Musk’s XPRIZE, the goal is to reduce the amount of carbon being released into the atmosphere by finding practical uses for it.

The organizers have received applications from 1,133 teams for the current Carbon XPRIZE so far, and applications will remain open through next year.

Two of the three Nova Scotian companies competing — Reazent and Planetary — were originally founded elsewhere before relocating to the province.

Founded in Ottawa in 2018, Planetary has developed a system to convert alkaline rocks left over from mining operations into a substance called bicarbonate, which it will release into the ocean to counteract ocean acidification and chemically extract carbon dioxide from the atmosphere. An alkaline substance is one with a pH greater than seven — essentially the opposite of an acid.

The process is the brainchild of Chief Technology Officer Greg Rau and creates hydrogen as a byproduct, which the company sells, as well as carbon credits.

Last month, the company – formerly known as Planetary Hydrogen – said it had raised $7.8 million, including $4.2 million of equity funding and $3.6 million of grants.

Reazent, meanwhile, was founded in India and moved to Nova Scotia as part of the AscendBio program, which works with industrial life sciences companies that use the fermentation facilities at the Verschuren Centre in Sydney. Reazent had been accepted into the IndieBio program in 2020 in Silicon Valley, just as its founder Sumit Verma prepared to move to Nova Scotia.

The company is developing organic bio-stimulants – fertilizers and pesticides that protect plants against disease and increase crop yields.

And CarbonCure, based in Dartmouth, sells technology to inject carbon dioxide into concrete, sequestering it and strengthening the end product. Concrete is the second most abundant man-made material in the world. And cement, its key ingredient, is responsible for an estimated 7 percent of global carbon dioxide emissions.

CarbonCure has also attracted the attention of high-profile cleantech investors, including the Breakthrough Energy Ventures whose investors include Bill Gates and Jeff Bezos.

“Team CarbonCure is in it to win it, and we want to make history by being the first team to win two prizes,” said CEO Robert Niven.

Editors Note: We ran an  article earlier this week stating  that Planetary Technologies and Reazent were in the Carbon Removal XPRIZE competition. We then learned that CarbonCure was also in the mix and that two of the three Nova Scotian entrants were in the running for the Milestone awards. So we updated the article in time for Earth Day.