A brand new power-generating system from Massachusetts Institute of Technology (MIT) researchers creates energy “out of what seems like nothing,” according to chemical engineering professor Michael Strano. Their system, which they’re calling a thermal resonator, harnesses daily swings in ambient temperature, potentially enabling remote sensing systems to operate for years without batteries or other power sources.
Nine MIT scientists from the chemical engineering department envisioned a new way to transform temperature changes into electric power. Their system doesn’t need two different temperature inputs simultaneously; it simply draws on fluctuations in the temperature of the air. Strano said, “We basically invented this concept out of whole cloth. We’ve built the first thermal resonator. It’s something that can sit on a desk and generate energy out of what seems like nothing. We are surrounded by temperature fluctuations of all different frequencies all of the time. These are an untapped source of energy.”
MIT said the power levels the thermal resonator can generate are modest at this point, but the system’s advantage is that it isn’t affected at all by short-term changes in environmental conditions, and doesn’t require direct sunlight. It could generate energy in oft-unused spaces like underneath solar panels. The researchers say their thermal resonator could even help solar panels be more efficient as it could draw away waste heat. The thermal resonator was tested in ambient air, but MIT said if the researchers tuned the properties of the material used, the system could harvest other temperature cycles, such as those of machinery in industrial facilities or even the on and off cycling of refrigerator motors.
The scientists created what MIT described as a “carefully tailored combination of materials” for their work, including metal foam, graphene, and the phase-change material octadecane. MIT said, “A sample of the material made to test the concept showed that, simply in response to a 10-degree-Celsius temperature difference between night and day, the tiny sample of material produced 350 millivolts of potential and 1.2 milliwatts of power — enough to power simple, small environmental sensors or communications systems.”