Scientists have developed a new kind of solar cell which could capture significantly more of the energy from the sun than current cells. These new solar cells could increase the maximum efficiency of solar panels by over 25%, according to scientists from the University of Cambridge.
Solar panels work by absorbing energy from particles of light, called photons, which then generate electrons to create electricity. Traditional solar cells are only capable of capturing part of the light from the sun and much of the energy of the absorbed light, particularly of the blue photons, is lost as heat. This inability to extract the full energy of all of the different colors of light at once means that traditional solar cells are incapable of converting more than 34% of the available sunlight into electrical power.
The Cambridge team led by Professor Neil Greenham and Professor Sir Richard Friend has developed a hybrid cell which absorbs red light and harnesses the extra energy of blue light to boost the electrical current. Typically, a solar cell generates a single electron for each photon captured. However, by adding pentacene, an organic semiconductor, the solar cells can generate two electrons for every photon from the blue light spectrum. This could enable the cells to capture 44% of the incoming solar energy.