100 Times More Efficient Solar Panels


Scientists working at the Stanford Institute for Materials and Energy Sciences (SIMES) have announced a bold innovation in solar energy making it 100 times more efficient than its previous photovoltaic design. Scientists have further claimed on improving - the 100 times better device - yet again by a factor of 10 in the near future which will make it 1000 times more capable than the current technology. What's even bolder is that the process could reduce the costs of solar energy enough to make it competitive with oil while being robustly sustainable.

The current model of photovoltaic cells (using silicon as semiconductor material to convert energy from photons to produce electricity) can only use a portion of the light spectrum with the remainder generating heat which accounts for 50% energy loss. The new device on the other hand is based on the photon-enhanced thermionic emission (PETE) technology which combines the light and heat of solar radiation to generate electricity.  PETE uses a special semiconductor chip to make electricity by using the entire spectrum of sunlight, including wavelengths that generate heat. “Concentrated sunlight heats up the devices semi conductor cathode to more than 400°C. Photo excited electrons stream out of the cathode’s nano textured underside down to the anode surface. Electrons are collected as direct electrical current. Solar and device heat is collected below the anode to run electricity generating steam turbines or Stirling engine.” (Standford, PETE)



In application PETE could be added to utility-scale concentrating solar power plants, such as multi-megawatt power tower and parabolic trough projects in California's Mojave Desert, to increase their electrical output by 50 percent.  Nanostructures of PETE used were made with combination of silicon, silicon carbide, gallium arsenide, doped diamond, and silken-geranium compounds. Other new materials are on the drawing board as the chips must eventually withstand 500 degree Fahrenheit daily temperature swings at solar power plants as they heat up during the day and cool down at night.