Startups are on the Verge of Transforming Concrete

Concrete has served as the foundation stone – literally – of the construction industry for hundreds of years. Now startups and companies around the world are discovering ways to make the building materials more friendly to the environment, according to Fast Company. From silicate rock, to CO2 itself, and even coffee grounds, there are a myriad of  ingredients for making concrete greener.

Releases more emissions than flying
Concrete is everywhere. From houses to skyscrapers, it is the primary building material of the modern age. However, the process of manufacturing concrete is one of the most environmentally unfriendly processes in the world. It makes up almost twelve percent of global carbon dioxide emissions, reported the Washington Post. This is more than the percentage of emissions released by the air-travel industry. 

Concrete is essentially a mixture of cement, sand, and water, which doesn’t seem all that destructive. But what makes concrete so environmentally unfriendly is  the way it is made. Limestone is heated in a kiln to incredibly high temperatures. The heat causes the two main elements that make up limestone, carbon dioxide and calcium oxide to unbind. The calcium oxide then becomes the binding agent for stone, sand and water, making concrete, while the carbon dioxide is released into the atmosphere. 

So not only is carbon being released into the air by the energy used to heat the limestone, the limestone itself emits a huge amount of the element as it unbinds. 

“The biggest barrier to entry in terms of either decarbonizing cement or steel, or coming up with an alternative product that can be swapped in for one of those structural material, is typically the testing,” Stacy Smedley, executive director at Building Transparency, a nonprofit focused on decarbonizing construction told The Washington Post.

Creative thinking
Luckily, a number of start-ups throughout the world are using creative thinking to make the construction industry a whole lot more friendly for the planet. 

According to Yahoo News, a Canadian company called CarbonCure, has ironically found a way to inject concrete with carbon dioxide itself. Not only does this trap the carbon dioxide into the concrete, keeping it from floating away into the atmosphere, it also creates a super strong material called calcium carbonate, which reduces the total amount of concrete that needs to be used. 

CarbonCure is working with construction companies – like Vulcan Materials  – to get this new greener technology into more concrete.  

California-based Brimstone, is creating carbon-negative cement by doing away with limestone entirely and instead using silicate rock, a material that does not release carbon dioxide when heated, reported the Washington Post. Instead, the process  produces magnesium, an element that absorbs carbon dioxide, as the basis for their concrete. 

“Being able to fit into existing standards,” Anu Khan, a carbon removal expert at the environmental nonprofit Carbon180 told The Washington Post; “is really powerful for commercialization.”

Additionally, researchers at Australia’s RMIT University, have recently released a study showing that adding coffee grounds instead of sand to concrete could make it much stronger, reducing both the amount of sand used, as well as the amount of concrete that would need to be used in the final product. 

The biggest barrier at this point is convincing members of the industry that the new types of concrete are safe to be used, according to Smedley. “Construction is a risk-averse sector,” she said. 

Hopefully these new and creative solutions to the environmental problems of concrete will soon be widely adopted. Given the significant part the construction industry has in releasing carbon dioxide into the atmosphere, great improvements can be made when more environmentally-friendly materials are used.