Concrete is one of the most widely used construction materials globally. With some modifications, it has the potential to also power our homes.

At a laboratory in Cambridge, Massachusetts, a set of polished black concrete cylinders are submerged in liquid and connected by wires on a bench. To an untrained eye, they appear inactive. However, when Damian Stefaniuk flips a switch, the blocks of man-made rock connected to an LED start to glow.

This ordinary, dark concrete chunk could signify the future of energy storage. Stefaniuk and his concrete are part of the solution. He and his team at the Massachusetts Institute of Technology (MIT) have discovered a method to create an energy storage device called a supercapacitor using three affordable, common materials: water, cement, and carbon black, a soot-like substance.