GENERATE POWER FROM TEMPERATURE SWINGS
In the quest to harness renewable energy, thermoelectrics have been boxed out by solar panels and wind farms. With good reason: Thermoelectric generators, which create electricity from a difference in temperature, have been expensive and difficult to deploy. The Mars Curiosity rover uses one to draw power from a radioactive heat source and the cold of Mars, but you wouldn’t want a pack of decaying plutonium isotopes recharging your phone. Now, researchers at MIT professor Michael Strano’s lab have found a way to create a heat difference for thermoelectric power from daily temperature swings in a device they call a thermal resonator. It uses two layers around a thermoelectric core that are engineered to change temperature at different rates so that they’re never the same. A suitcase-like prototype ( pictured) on the roof of the lab building produced 1.3 milliwatts of power from an average day’s 10°C swing. That output may be small, but the technology can be scaled up for low-wattage electronics, says Strano. His lab has already received a grant to build a resonator-powered communications network for disaster zones that will allow first responders to communicate without a working power grid.
MIT’S prototype generator.