Australian researchers have unlocked the secret to squeezing more energy out of sunlight, by converting otherwise wasted sunlight into useful light, that could provide a way to significantly boost to solar panel efficiencies. The research, led by scientists from the University of New South Wales and published in the journal Nature Photonics on Tuesday, outlines a new method for ensuring more of the sun’s energy can be converted into useful electricity by using sunlight that would otherwise be wasted as heat. In a photovoltaic solar cell, sunlight is converted into electricity through a process called the photoelectric effect, where individual packets of light, called photons, transfer their energy onto electrons within the solar cell material.
However, the researchers from the University of New South Wales have unlocked a way to combine the energy from several “low energy” light packets, into a “high energy” light packet, that can then be used to produce electricity. By adding up the energy from a number of low energy photons, the researchers found a way to surpass the “bandgap” and use otherwise lost solar energy to produce electricity. The researchers believe that this “upconversion” of low energy photons could be a pathway to boosting the efficiency of solar cells. While US-based researchers have demonstrated the successful combination of energy from multiple photons previously, the UNSW team have successfully demonstrated the ability to bridge the “bandgap” in silicon for the first time.
The researchers said that the research was still in its early stages, and further work was necessary before we will see the technique used in commercially available solar panels. “This is only an early demonstration, and there’ quite a lot of materials development needed to make commercial solar cells, but this shows us it’s possible,” professor Schmidt added.
Source: Renew Economy
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