Researchers from the University of California, Davis, have announced a new invention that could harness solar power at night. They published a paper in ACS Photonics that explained how new technology could use a different process than solar panels to generate energy around the clock. The team that published these findings is currently working on building prototypes.
This technology could represent a turning point in sustainable power. Scientists from around the globe have been working for decades to make our way of life more environmentally friendly. One of the most critical aspects of this effort is the attempt to generate reliable alternative energy.
Fossil fuels are still the largest source of energy, accounting for more than half of America’s electricity generation. These sources are nonrenewable, and using them releases harmful pollutants into the atmosphere. Nevertheless, they remain as the world’s chief energy source, mostly due to convenience and cost.
Researchers and companies alike have tried to make the shift to renewable energy for some time, but most alternatives still have their share of drawbacks. Some methods are expensive or inefficient, and storing alternative energy has proven difficult.
Solar radiation provides a widely available, renewable source of power, but current solar panels have limited effectiveness. The most apparent drawback is that they can’t generate electricity at night. While battery storage for solar energy is improving, this limitation also means it may not be able to keep up with demands.
The technology proposed by the UC Davis researchers might revolutionize solar power. Being able to work 24 hours a day would significantly improve the viability of this form of energy. To achieve this, the team is developing what they call an “anti-solar panel.”
Anti-Solar Panels
As made clear by their name, these anti-solar panels work in a way opposite to traditional ones. Whereas current versions draw energy coming from the sun, anti-solar panels use heat radiating off the Earth’s surface.
Traditional solar panels use photovoltaic to absorb photons from the sun’s radiation, which the system then uses to generate an electric charge. They can draw in this radiation because they’re cold compared to the sun. Since heat always moves to an area of lower temperature, it will pass into the solar panels.
Anti-solar panels work according to the same basic principle, but in reverse. Air grows colder at night, so heat radiates from the Earth’s surface — which warmed during the day — toward space. In a phenomenon known as radiative cooling, this heat radiates in the form of infrared light, which these new devices can use to generate electricity.
Radiative cooling is already in use in other applications. Researchers have looked into using the process to cool homes more sustainably. However, instead of moving heat to make an area more comfortable, anti-solar panels do it to harvest energy.
This process doesn’t equal the amount of energy generated during the day. The researchers estimate that the devices could produce around 25% of the electricity that traditional solar panels do in the day. While this number may seem small by itself, it represents a sizeable increase in energy overall, since current systems don’t operate at all during the night.
Anti-solar panels could increase solar farm energy production by 12%, according to the paper. As technology develops, this number could grow. Even if it doesn’t, any rise in the efficiency of alternative energy can be advantageous.
