After water, concrete is the second most used material in the world and accounts for around eight per cent of the world’s greenhouse gas emissions. Only coal, oil and gas emit more. Cement, one of the key ingredients of concrete, is particularly problematic — if it were a country, it would be the third largest emitter of GHG emissions on the planet after China and the U.S. Niven thinks that tackling such a large problem is what made them stand out from other prize competitors.

“After that it was a matter of designing the right technologies that were retrofit so they could be very easily adopted and that provided an economic incentive as well,” says Niven. “That really was the recipe for us to win the award that was really looking for the most scalable solution.”

“Concrete is a material that can be readily made using CO2 as an input, which the winning teams have demonstrated really clearly,” says Marcius Extavour, executive director of the Carbon XPrize. “Now, deploying their technology to avoid and reduce emissions from heavy industry will be a gamechanger for global decarbonization in the fight against climate change.” 

According to Niven, the idea behind the technology isn’t an original one. The process of taking carbon-dioxide and reacting it with calcium, then reforming it as calcium carbonate is seen often in nature — the formation of coral reefs or shells, for example. However, what CarbonCure is doing is much faster, and takes place in concrete rather than in seawater.

With the prize money, Niven hopes to accelerate global deployment of the process to hit their target of reducing embodied carbon in the built environment by 500 megatonnes annually by 2030. The money will also go toward developing other new technologies that use carbon-dioxide productively, as well as starting a social impact initiative.