Technological advances could drastically cut greenhouse gas pollution from concrete

By Eric Sundquist
Most GHG emissions in transportation come from on-road vehicles, but construction is a large contributor as well. In particular, concrete manufacturing generates emissions both from energy needed to heat materials in cement kilns and from a chemical process known as “calcination.” Because concrete is so widely used these emissions are substantial, amounting to an estimated 5 percent of the world’s carbon dioxide emissions.
Cement kilns have improved their efficiency to some extent over time, but now the New York Times reports that a more substantial improvement may be on the way. A New Jersey-based startup, Solidia Technologies, has begun to commercialize a process that it claims reduces GHG emissions by up to 70 percent. The technology relies on lower-emission cement chemistry, and it sequesters carbon dioxide—from a companion industrial or power plant—during hardening.
The technology is currently being used for products such as walkway and driveway pavers, including some products sold by E.P. Henry in the United States. Poured and precast structural concrete using this technology is not yet available, but that time may come soon.
The Times cited Jan van Dokkum of the venture capital firm Kleiner Perkins:  “Solidia may now be at the stage where solar power was a decade or more ago. A relatively few early adopters and government subsidies helped solar gain acceptance until the prices of panels came down, opening the way to today’s huge market. ‘Once we get this transition going,’ he said, ‘then suddenly this thing will boomerang through the industry.’”
Eric Sundquist is Director of SSTI.