New Device Can Generate Power Anytime and Anywhere Just From Changes in Temperature

The new technology has an advantage over solar power because it doesn't need direct sunlight SEBASTIEN BOZON/AFP/Getty Images

Scientists have created an entirely new way to generate electricity—anytime, anywhere. The device, known as a thermal resonator, can harness energy from temperature fluctuations happening all around us. Scientists from the Massachusetts Institute of Technology are working on accessing this "untapped energy source," which can function regardless of rain or shine, according to the new study's senior author, Michael Strano.

The unusual source of energy is drawn from the natural ebbs and flows of temperatures. The most obvious fluctuations, Strano said, are the changes between day and night. Large changes such as those generate the most power, but even minute temperature differences all around us can generate electricity.

"We're actually surrounded by temperature fluctuations," Strano said. Sometimes, the temperature changes slowly, like outside—it changes over a 24-hour cycle. But even around the human body, if you were to carry a thermometer in your pocket, you would find it fluctuating every few seconds."

These temperature changes are constant and surround us everywhere we go, Strano explained. "We sit in a giant temperature bath, and when that bath fluctuates, you basically can generate electrical power," he said.

The thermal resonator, which appears like a black box, can use those constant temperature changes to generate electricity through a special material created at MIT. The material is made from metal foam coated in graphene and combined with a wax called octadecane, as detailed in the researchers' study published mid-February in Nature Communications. The thermal resonator is filled with this material, which can both absorb and store heat.

Close-up view shows the thermal resonator, which appears like a black box. Melanie Gonick

After months of testing on the roof of an MIT building, researchers discovered that enough electricity could be generated to power LED lights, small computers and even batteries. Because the device works regardless of whether it is sunny or not, it has an advantage over solar power, too. Clouds, winds, or even sand, which often covers up solar panels in the middle of deserts, wouldn't affect its ability to harness power from the ever-changing temperatures. The device could even be retrofitted beneath a solar panel, bolstering the energy potential. This way, excess heat with energy potential isn't wasted.

It could be used in a variety of ways too. Since the material incorporated into the box isn't delicate or made from fragile parts, it could be buried underground or incorporated into building structures. The device could go as far as other moons or planets, powering up landers and rovers with just enough power to keep moving, but lasting long enough for space missions.

The team’s test device, which has been deployed on the roof of an MIT building for several months, was used to prove the principle behind their new energy-harvesting concept. Justin Raymond

It's a new field, Strano noted, but as more scientists continue to work on this way of generating power, more electricity could eventually be generated. Strano and his team have been researching this power source for around one year, and they are already thinking of starting a company to eventually commercialize the thermal resonator. This way of generating power is "more than just an invention," said Strano. "It's a new mechanism for generating electrical power."