Their innovation comes in the form of a new device that consists of two transparent polymer layers, which are placed on top of a designated solar photovoltaic (PV) cell. It said that the device can then just be left there. As soon as raindrops fall onto them and roll off, the ensuing friction is enough to generate a so-called static electricity charge.
According to Baoquan Sun, one of the researchers who invented the new device from Soochow University, their raindrop-powered solar panel add-on was created to squeeze even more electricity from panels where they are present. "Our device can generate electricity in any daytime weather," he said. "In addition, this device even provides electricity at night if there is rain."
Although they were not the first to create such a device, what the researchers made still counts as an innovation. Similar devices on solar panels have already been invented by other researchers, and they are known as triboelectric nanogenerators (Tengs). But the researchers managed to improve upon the current standard formula by coming up with something that is much simpler and also more efficient. They did this by making one of the polymer layers act as the electrode for both the solar cell and the Teng itself.
According to Sun, their methods have allowed them to create a highly versatile device that may have a number of different applications in the future. "Due to our unique device design, it becomes a lightweight device," he said. "In future, we are exploring integrating these into mobile and flexible devices, such as electronic clothes. However, the output power efficiency needs to be further improved before practical application." (Related: Solar panels to become future source of toxic e-waste.)
The details of their new device as well as how they managed to come up with it have been laid out in full in a new research paper titled, "Integrating a Silicon Solar Cell with a Triboelectric Nanogenerator via a Mutual Electrode for Harvesting Energy from Sunlight and Raindrops," which was published recently in the journal ACS Nano. It will be easy to understand if you familiarize yourself with nanogenerators, particularly Tengs, and how their technology could be applied on a very small scale in order to accommodate raindrops.
According to Varun Sivaram, an industry expert from the Council on Foreign Relations, U.S., the researchers have managed to create an ingenious device. "The idea is interesting – a hybrid device that harvests kinetic energy from water without destroying the output of the solar cell during sunny times," he said. "There's lots of nice engineering, like using one layer to do double duty as a component of the Teng as well as trap light for the solar cell."
The only thing that needs to be done about this new device at this point is to further optimize it and make it truly viable for commercial use. At this point, it's simply not practical enough for the real world. But with a little tweaking, it could be a good way to complement existing solar panel technology.
Find out other methods used to improve renewable energy sources at Power.news.
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