Bacteria and urea turn sand into concrete

Cement is an energy-intensive product. Making it means heating limestone to 2642 degrees Fahrenheit. As a result, 5 percent of the entire world's carbon dioxide emissions come from cement production. Unsurprisingly, there are lots of scientists searching for more-sustainable solutions to cement and the concrete it's the primary ingredient in. One of the newest: A process that stiffens sand with the help of bacteria and urea.