Micro-scale Optimized Solar-cell Arrays with Integrated Concentration
ARPA-E’s MOSAIC program seeks to develop technologies and concepts that will lower the cost of solar photovoltaic (PV) power systems and improve their performance. Project teams will develop micro-scale concentrated photovoltaic systems (CPV) that are similar in cost and size to conventional solar PV systems, but with greatly increased performance levels. Multidisciplinary teams will leverage expertise in conventional flat-plate PV, CPV, manufacturing, optical engineering, and material science to produce a new class of PV panels. If successful, these technologies could facilitate cost-effective deployment of solar power systems across a wide range of geographical locations, lowering U.S. greenhouse gas emissions and reducing dependence on imported energy.
Three types of solar power exist commercially: solar photovoltaic (PV), concentrated photovoltaic (CPV), and concentrated solar power, or solar thermal power. Solar PV, which is the most widely used type of solar system, offers a clean, renewable source of electricity at a cost that is increasingly competitive. Although it has experienced dramatic growth and cost reductions in recent years, solar PV represents only 1.1% of U.S. power generation capacity. Many roofs are too small, too shaded, or sub-optimally oriented for installation of today’s PV panel technology to be economical. Although efficiency improvements have increased solar PV’s ability to convert solar energy to electrical power, further gains will become difficult due to physical limits on their performance. Additionally, future growth of solar power systems will be limited by the cost of the systems and the space they require. Enhanced performance and cost reductions are necessary in order to substantially increase solar penetration beyond current levels. One way to increase the efficiency of solar PV systems is by using CPV modules, which use optical devices to concentrate sunlight onto a smaller, very high efficiency solar PV receiver. This allows the system to generate more power with a much smaller footprint. However, CPV only converts direct sunlight, not diffuse solar radiation (sunlight scattered by the atmosphere and clouds), and therefore CPV is only viable in a limited geographic range, namely the southwestern U.S. where direct sunlight predominates. CPV is also currently very expensive because of the materials that are used in the receiver. MOSAIC seeks to overcome these challenges and develop arrays of very small CPV systems (known as micro-scale CPV technology) that integrate more affordable materials and manufacturing techniques. In addition, MOSAIC seeks solutions that will utilize diffuse sunlight as well as direct sunlight in order to expand the geographic regions in which the benefits of CPV may be exploited cost-effectively.
MOSAIC’s goal is to lower the cost of solar systems by using integrated concentration to significantly increase PV module efficiency without increasing manufacturing costs. This will allow for expanded cost-effective use of solar power in all three primary market sectors – residential, commercial, and utility.
Expanded use of clean, renewable solar power could reduce dependence on foreign sources of energy.
Solar power offers clean power generation with zero emissions. Further, technologies developed under MOSAIC may also enable solar installations with smaller physical footprints, reducing the environmental impacts of large solar arrays.
Technologies developed under MOSAIC could offer a cost-effective option for clean, locally produced power across all market sectors.