In recent years, there’s been plenty of talk around solar energy and how it can potentially solve the power problems of today’s world. Perhaps the future of global power generation is not only about harnessing the sun’s energy. Maybe the future is also about harnessing the energy of “the element that takes over the planet once the sun goes down” – darkness!
Solar panels commonly generate electricity from the Sun through a physical process called the photovoltaic effect (light exposure on certain materials generates an electric current), but others work through thermal processes – the Sun is hotter and Earth is cooler, and the difference in temperature can be converted into usable energy. The researchers devised a system based on the alternative process, in which Earth is the source of heat.
Today, scientists have created something of a reverse solar cell: a tool that generates electricity from the darkness of night. By some, it is called “anti-solar panel” and this device has the potential to bridge the gap left by solar energy, collecting energy from the night sky.
The researchers have tested their system with a very small prototype. The device was a 20-centimeter (8-inch) aluminum disk painted black and hooked up to commercial thermoelectricity generators.
It successfully created enough energy to power a single small LED lightbulb, a small success obviously, but with huge potential and also it is possible that the device could act in reverse during the daytime, absorbing sunlight and producing electricity from a heat traveling from the sun to the disk and into the outside environment.
Credit: Aaswath Raman
If sometimes they are able to refine the system to produce anywhere close to as much energy as a standard solar panel, it could completely transform the renewable energy sector. It can provide a way to generate electricity at a time that solar panels can’t and it’s cheaper to make.