Plants absorb sunlight and convert it to energy with nearly perfect efficiency—none of the energy goes to waste. Electrical engineers are always striving for that kind of efficiency, but nowhere is it more pronounced than in solar panels. Even the best of these can only convert about 44 percent of the light it absorbs into usable energy, and that’s part of the reason why solar energy doesn’t fulfill more of the world’s energy needs.
How are plants so efficient? They’re able to take advantage of some quirks in quantum mechanics, often called quantum weirdness. When a photon hits a plant’s special light-sensing chromatophore, it releases a quantum particle of energy called an exciton. Eventually the exciton makes its way to the part of a cell where it’s absorbed and be put to use in the body. Thanks to quantum physics, no energy is lost in the process.
By changing viruses’ DNA, researchers from MIT have been able to take advantage of quantum weirdness. The result could be solar panels that transmit energy with unprecedented efficiency, according to a proof-of-concept study published this week in Nature Materials.
In the study, the researchers changed the DNA of viruses so that they would bind with groups of synthetic chromophores, and light up when they did, so the researchers could monitor them using laser spectroscopy. They tested different types of viruses and different chromophore molecules in varying concentrations in a solution and they were able to show that the viruses and chromophores did have a meaningful transfer of energy. And though they haven’t yet found the ideal combination, the researchers were able to make the excitons travel at double the speed of those in existing solar cells, and to do so at much longer distances.
So far these viruses can’t produce their own electricity as plants do; they can only transmit it, as the press release notes. But the researchers write that more efficient energy transfer that scientists are able to control could have a number of applications across several scientific disciplines. They could create catalysts for chemical reactions driven by light, or create more efficient electronics, including solar panels.