Stanford University scientists have developed a solar panel capable of generating electricity in the dark. This overcomes the main drawback of traditional solar panels, which cannot produce power in darkness. The findings were published in the journal Applied Physics Letters in April 2022 and showed that existing solar panels could also be modified to work at night, saving costs for businesses and households that won't have to replace them.
The method used to make older solar panels generate electricity in the dark is known as "radiative cooling." It exploits the release of heat into the air as the Earth cools down after sunset, creating a temperature difference between the air and the panels. The energy produced by radiative cooling can be harnessed by installing thermoelectric generators onto the panels.
The concept of using radiative cooling to generate electricity in the dark is not new. In 2020, researchers from the University of California presented a similar idea, dubbed an "anti-solar panel." Photovoltaic solar panels already utilize radiative cooling to generate power after sunset, thus enabling them to operate in the dark.
Sun Energy in the Dark
This technology hasn't received widespread attention due to its limited energy output compared to traditional solar panels. It's estimated to generate only about 25% of the energy produced by a typical solar panel in a day. Nonetheless, it still provides a source of clean energy that wasn't available before, making it worth utilizing, according to the WE Forum.
Aside from radiative cooling, other advancements in solar power enable panels to generate electricity without sunlight. These utilize ultraviolet light, similar to what fruits and vegetables rely on, to produce energy. Standard solar panels only operate during the day, requiring costly battery storage to use the solar-generated power at night. However, a group at Stanford University has tested solar panels that continuously generate electricity.
BGR News stated that these panels exploit the natural cooling process of solar panels at night and generate power from the temperature difference between the cooling panels and the warm air around them. A thermoelectric generator is used to convert heat transfer into electricity.
An Upgrade to Existing Solar Panels
The panels were constructed using readily available components and have the potential to provide a reliable, continuous source of power to the estimated 750 million people globally who lack night-time electricity access. Additionally, the thermoelectric generator enhances the output of the solar panels during the day by working in reverse, producing electricity as the panels heat up. According to the Stanford team, upgrading existing panels with this technology should be simple.
According to a previous statement from NPR, the new approach can provide lighting and power during nighttime for off-grid and mini-grid systems, where solar cell installations are becoming more popular. Mini-grids refer to independent power networks used when a certain population is too remote or small to be connected to the main grid.
Solar energy has recently become more accessible due to its decreased cost, which has led to increased investment and incentives in the solar industry, especially in California. Abigail Ross, the CEO of the Solar Energy Industries Association, emphasizes the importance of ramping up clean energy production and reducing dependence on hostile nations for energy needs in light of global supply uncertainty.
RELATED ARTICLE : Long-Term Solar Energy Saving Now Possible, Storage Up to 18 Years
Check out more news and information on Solar Energy in Science Times.
