Scientists at Harvard may have discovered how to utilize an entirely new renewable energy source — the Earth’s infrared emissions into outer space. Heated by the sun, our planet continuously leaks an astounding 100 million gigawatts of energy into the frigid vacuum beyond. Capturing only a fraction of that would be enough to power all of humanity’s activities.
How can this be done? It’s not immediately obvious, admits lead researcher Professor Federico Capasso: “To generate power by emitting, not by absorbing light, that’s weird. It makes sense physically once you think about it, but it’s highly counter-intuitive.” His Harvard team has devised a potential solution in a device called an “emissive energy harvester” (EEH). Its most practical form resembles a solar panel, except instead of catching incoming light, the cell releases infrared radiation to generate energy.