A new form of concrete, stronger and with a lower carbon footprint, has been created by researchers utilizing some of the waste products of biofuel production. Concrete has a rather significant carbon footprint, accounting for between 3-8% of global carbon dioxide emissions. The development of a concrete with a much lower carbon footprint could be significant, researchers say. In order to cut back on the carbon footprint of concrete, the researchers from Kansas State University have been looking for environmentally-friendly materials to replace the portland cement.