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The cement that could turn your house into a giant battery
Concrete is perhaps the most commonly used building material in the world. With a bit of tweaking, it could help to power our homes too
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For now, the concrete supercapacitor can store a little under 300 watt-hours per cubic metre. Getty Images |
On a laboratory bench in Cambridge, Massachusetts, a stack of polished cylinders of black-coloured concrete sit bathed in liquid and entwined in cables. To a casual observer, they aren't doing much. But then Damian Stefaniuk flicks a switch. The blocks of human-made rock are wired up to an LED – and the bulb flickers into life.
"At first I didn't believe it," says Stefaniuk, describing the first time the LED lit up. "I thought that I hadn't disconnected the external power source, and that was why the LED was on.
"It was a wonderful day. We invited students, and I invited professors to see, because at first they didn't believe that it worked either."
The reason for the excitement? This innocuous, dark lump of concrete could represent the future of energy storage. [continue]
