The production of cement, the primary component of concrete, accounts for 5 to 10 percent of the world’s total carbon dioxide emissions; the process is an important contributor to global warming.
Cement is manufactured at the rate of 2.35 billion tons per year, enough to produce 1 cubic meter of concrete for every person in the world.
If engineers can reduce carbon dioxide emissions in the world’s cement manufacturing by even 10 percent, that would accomplish one-fifth of the Kyoto Protocol goal of a 5.2 percent reduction in total carbon dioxide emissions. [Science blog]