New cement absorbs CO2

huge amount of carbon when it is dug up and then releases even more when it is heated to 1,400 degrees Celsius (2,552 degrees Fahrenheit). When you consider that every year, some three billion tons of cement turn into nearly thirty billion tons of concrete, it is no wonder that the industry produces more CO2 emissions than the entire airline business, says Novacem CEO Evans.

Novacem’s cement, by contrast, is based on magnesium silicates that contain no stored carbon. Evans says there are world reserves of more than 10,000 billion tons of such silicates, which are the basis for materials such as asbestos and talc. Making cement from these silicates also consumes less energy, because it is only heated to 600 degrees Celsius (1,112 degrees Fahrenheit), and in the process, carbon is absorbed and fixed into the material.

The net result: For every ton of Portland cement replaced by Novacem, the atmosphere would be spared up to 850kg (1,873 lb.) of CO2.

Innovative fund-raising

Schenker quotes Evans to say that Novacem’s cement will be attractive to the construction industry, which is under pressure to get greener. In July the company announced the closing of an innovative fund-raising vehicle, in which it sold $1.5 million worth of Green Cement Bonds to investors including building materials giant Lafarge (LFRGY). The proceeds will be used to accelerate development and commercialization of Novacem’s cement, which also has the backing of the Royal Society, Britain’s national academy of science.

Subscribers to the bond are expected to participate in the company’s planned Series A financing round, which will be used in part to support the construction of a planned semicommercial plant that could produce up to 25,000 tons of carbon-negative cement per year. Novacem says it will work closely with bond subscribers in the development of this plant and the commercial-scale plants it expects to build later.

Schenker notes that Novacem does not have the field entirely to itself. A number of other companies — including Los Gatos, California-based Calera and Sriya Green Materials in Marietta, Georgia — are also making greener forms of cement, says Michael LoCascio, a New York-based senior analyst that heads up Lux Research’s green building and water unit. LoCascio says there is a huge opportunity for companies that can make building materials and buildings more energy-efficient.

Evans, the Novacem CEO who is a two-time winner of the WEF Tech Pioneer award, is betting on that. “The world is your oyster if you are a low-carbon technology pioneer,” he says.