UCLA and Stanford University researchers have developed a solar panel look alike panel that uses the coolness of the night sky instead of using the heat of the sun to produce electricity. It only appears like a solar panel but works in opposite way. They have published the results of their experiment in Joule, a scientific journal.
Scientists have proven that their new anti-polar device generates electricity after the sun goes down. Once the sun is down and not shining on the panel, its top side starts cooling down quickly. The underneath side of the panel though stays warm for a much longer period due to the radiant heat from the earth or a rooftop beneath it.
An electric current is created when the temperature difference pushes electrons through from one side of the electrically conductive material to the other. Scientists call it radiant cooling, or passive cooling. This is not a new but in fact a forgotten concept. 6000 years ago it was employed in the Middle East in the form of enormous beehive-shaped structures called yakhchal. This method allowed people to create and store ice in the desert.
When compared to a solar panel the darkness panel creates far less electricity- .5 watts per square meter only. Solar panel creates 200 watts per square meter of electricity. The researchers are though hopeful that the electricity created by darkness panel could be useful for low-wattage night time applications as solar is not available then.
Scientists are expecting the technology to improve with time and to produce 4 watts per square meter. This is a good news as the material used to make the panels would be far cheaper than the photovoltaic cells used in solar panels.