A Nova Scotia company that injects carbon dioxide into concrete — making it stronger while lowering its carbon footprint — has taken home a multimillion-dollar prize in a global competition aimed at tackling climate change.

CarbonCure Technologies is one of two grand prize winners of the NRG COSIA Carbon XPrize, which began in 2015, lasting three rounds over the course of 54 months, according to a news release on the company's website.

The goal of the competition was to create technology that converts CO2 emissions into valuable products. Other contenders had innovations like harnessing photosynthesis to convert carbon and transforming acid rock draining and CO2 emissions into a stable substance.

Each grand prize winner gets $7.5 million US, equivalent to about $9.4 million Cdn.

The other winner is Los Angeles-based UCLA CarbonBuilt, which also developed a technology that reduces the carbon footprint of concrete by injecting CO2 into the mixture.

CarbonCure's prize money will be put to use reaching the company's goal of reducing 500 million tonnes of carbon emissions annually by 2030, the company said in the release. It also plans to invest a portion of the funds into social equity initiatives.

The company's founder, Rob Niven, told CBC News the Carbon XPrize was worth the time and effort the company spent to win.

"Yes, the cash reward was very significant," he said in an interview from British Columbia.

"But what it would also do is create a catalyst for market recognition and credibility that would really propel our business forward. It's such a global high-profile award and being the nature of our business, being a global product and technology, it really felt like it was a great opportunity."

The use of CO2 in concrete is expected to become a $400 billion market, the company said in a release. Its concrete solution is currently used in more than 300 concrete plants around the world.

Annually, buildings make up 40 per cent of global greenhouse gas emissions, and the world's building stock is expected to double by 2060, according to Marcius Extavour, executive director of the Carbon XPrize.

"CarbonCure's solution for the concrete industry exemplifies XPrize's ideal innovation — it is effective, commercially viable, and scalable — and can make a real difference to climate change today," Extavour said in a release.