Scientists from MIT developed a device known as a thermal resonator that produces electricity from air temperature cycles that occur between day and night or through temperature fluctuations. The researchers have been studying how temperature fluctuations could generate energy for the past few years.
The discovery described in the journal Nature Communications suggests the use of thermoelectric principle, which could generate electricity through temperature differences between two sides of a material of the device. Once the heat passed from the hotter side of the material to the cooler side, the charge carriers flow with it and produce a voltage difference, resulting in electricity being generated, according to New Atlas.
Michael Strano, the co-author of the study, said they have built the first thermal resonator. He further said that it is something that can sit on a desk and produce energy out of what seems like nothing. He added that they are surrounded by temperature fluctuations of all various frequencies all of the time and these are an untapped source of energy.
The newly developed thermal resonator has a copper or nickel foam at its center, coated with graphene that enhances conductivity. It is also combined with an octadecane, which is a phase-changing material that acts as a storage device. The one side of the device captures the heat, while the other side is storing it. The heat could move back and forth because one side of the material is cooler than the other.
The scientists tested an initial device over 16 days. The temperature swings were about 10 degrees Celsius each day. With this, the system generated 350 millivolts of potential and 1.3 milliwatts of power. This device is relatively small, yet good for basic sensors or communication sensors, according to Engadget.
Meanwhile, if the scientists could augment the energy capacity, the thermal resonator could be used for specific applications. These include backups for existing renewable energy, like if a solar panel were to go down. It may also have applications for planetary rovers, allowing them to potentially run for years, as the MIT scientists envision.