Electricity Trick Could Make Concrete Almost Carbon-Free

Concrete has a guilt problem. Every tonne of cement you pour into a dam, a bridge, a housing block, carries with it roughly 800 kilograms of carbon dioxide released during manufacture, roughly twice the weight of the cement itself. The industry accounts for about 8 percent of global CO2 emissions, which puts it on a par with all the world’s cars put together, or thereabouts. And yet fixing it has proven stubbornly, almost comically difficult. The problem isn’t just the energy needed to heat...