When solar power was conceptualised, it was created with the aim of rationalising the use of coal and petroleum for electricity. It was more sustainable and so much more environment-friendly. But, when technology is at hand, there is always scope for improvement, room for innovation. And guess what has been proved yet again?
We all know, that solar panels work in sunlight, right? This is simple mechanics by which the apparatus works. But, the rains wreak havoc on these solar panels. Otherwise rendered useless during rains, the solar panels have found a new way out. Truly a Darwinian achievement.
A group of researchers from Soochow University in China developed a solar panel that generates power during rains. The scientists used a technology that is called triboelectric nanogenerator (TENG), which creates charge or electricity through friction. As the raindrops fall on the surface, a certain amount of friction is created, as the water droplets roll off. These nanogenerators convert this mechanical energy created through friction, into electricity. This hybrid solar panel is a setup that not only has solar receptors, but also the TENG layers. The layers of TENG and solar cells are mounted together, but independent of each other’s functioning.
Image source: Business Insider
In the device, two transparent polymer layers are placed on top of a solar photovoltaic cell. As the rain falls, friction is generated which produces the static electric charge. The polymer layer becomes the common electrode for the solar cell, as well as the TENG. The electrode surface, which is textured, also prevents the unwanted reflection of light, which thus enhances the harvesting of sunlight. This very texture also causes a greater degree of contact between rain and the TENG, which then boosts the performance of the nanogenerator.
Image source: ASC Nano
While, this is an effective method of harvesting electricity, and we’d all very gratefully want to install it at every single one of our homes right now, there’s a catch. For starters, the energy conversion is not very profitable. It saves up and converts only a fraction of the energy that it takes in. It is less when compared to a 22% energy save of the solar cells. But, not to lose heart, if anything, this is a starting point basis which improvisations can be made to make it more efficient for the future.
Another shortcoming, though a minor one, is the fact that it all does not work together. The solar cell and the TENG, do not function simultaneously because of the common electrode. On a sunny day, you will be able to get solar power and on the day it pours, you can have rain-generated power. But, on the rare days that the sun is out, and it is raining, the device will give up one function, to facilitate the other.
Many such inventions and scientific experiments are making living more sustainable. For example, in Australia, scientists have used soybean cooking oil to derive a material called graphene. This is a carbon material which is stronger than steel and much lighter. It can conduct heat and electricity and is a flexible material that can be used for various purposes. Let’s give you an example. Graphene can charge an iPhone in 30 seconds! And like TENG, it can be used to harness electricity from rain. Coat a solar panel with graphene and we are good to go!
Image source: Reaction Digital Media
With science, anything is possible. All you need is the will to make a difference and the scientific knowledge to apply your learning for the advancement of mankind. While we may all not be scientific geniuses, we are keeping our fingers crossed and rooting for these sustainable developments.