Traditional Solar Technology
Traditional photovoltaic (PV) modules use semiconductors to generate electrical power by converting solar radiation into electricity. PV modules come in many forms, including crystalline silicon modules and thin-film modules based upon amorphous silicon, cadmium telluride and copper indium gallium selenide. Typically, polycrystalline silicon modules have efficiencies of ~14-15 percent, while thin-film modules have efficiencies of ~8-13 percent, depending upon the technology.
The Semprius Concentration Factor
Concentrating photovoltaic (CPV) modules work in much the same way as traditional PV modules, except that they use optics to concentrate the sun onto solar cells that do not cover the entire module area. This concentration factor - in Semprius’ case over 1,100 times - dramatically reduces the amount of semiconductor needed (<0.1 percent) and opens up the potential to cost-effectively use very high-performance multi-junction cells with efficiency levels greater than 41 percent. In order to work properly, however, CPV modules must accurately face the sun. Therefore, CPV modules are used in conjunction with high-performance trackers that intelligently and automatically follow the sun throughout the day. Other than this, CPV systems are built and operate much like traditional PV systems.
Driving Down the Cost
CPV technology is also distinct from PV in the way it drives down the cost of solar generated electricity. By selecting high-efficiency, high-performance semiconductors and implementing reliable tracking solutions, CPV attacks both sides of the cost equation - relentlessly reducing module and system costs, while increasing capacity factors and system output.
Key Advantages of Semprius’ CPV Technology
- High efficiency - world record module efficiencies up to 33.9 percent, two-to-three times greater efficiency than competing PV technologies
- High performance - industry-leading high temperature performance
- Low cost - in dry, sunny climates, capable of delivering the lowest levelized cost of electricity of all PV technologies
- Consistent daily energy production - by tracking the sun, generates very consistent energy production close to rated power throughout the day
- High energy density - high efficiency modules enable solar parks to have 25 to 50 percent higher capacity than fixed-tilt and single-axis tracked PV systems
- Light environmental footprint - pedestal tracker design does not require grading, minimizes permanent shading and allows for dual use of the land.