Temperature changes are taking place around us all the time, and scientists have created a device that can convert these fluctuations into electricity by feeding sensors and communication devices with the help of the surrounding air.
The energy is obtained by what is called a thermal resonator: a device that captures the heat on one side and emits it on the other. As both sides try and achieve balance, energy can be generated using the thermoelectric process.
According to the Massachusetts Institute of Technology team, the new thermal resonator can charge mobile devices such as smartphones or smart watches for many years.
This device is something that can sit on a desk and can generate energy from what seems to be nothing. Constantly, we are surrounded by temperature fluctuations at different frequencies. Obviously, these are still untapped sources of energy, and this device will change this.
American researchers’ innovation consists of the combination of materials used for the thermal resonator: metal foam, graphene and a special wax called octadecane, which changes the state of solid and liquid according to temperature fluctuations. Thus, the combination created a device capable of absorbing but also retaining heat, which is extremely rare in materials engineering.
When tested at a 10 degree Celsius difference, the day-night difference, a small sample of material produced 350 millivolts of potential difference and 1.3 millions of power, which is sufficient to keep small sensors and communication systems powered – without batteries or other sources of energy.
Moreover, the thermal resonator can work in any weather conditions and even in the shade. It only needs a temperature fluctuation. They can even be placed under the solar panels to absorb excess heat.
The next step in developing this technology is to test the device under more temperature-shifting conditions on a larger scale. One of the stakes is to create a backup system that comes into operation in the event of a power cut.
Another use of this new technology may be on the rovers that will be sent to explore other worlds, by generating energy from temperature fluctuations on that celestial body – taking advantage of the fact that there may be any temperature, even the extremely low temperatures on Mars. The study was published in Nature magazine.