Project Name: Optimization of Concentrator Photovoltaic Solar Cell Performance Through Photonic Engineering
Funding Opportunity: PVRD
SunShot Subprogram: Photovoltaics
Location: Stanford, CA
SunShot Award Amount: $700,000
Awardee Cost Share: $98,795
Project Investigator: James Harris

This project is focused on improving the design of concentrator photovoltaics (CPV) technology, which uses lenses and curved mirrors to focus sunlight onto small, highly efficient multi-junction solar cells. The new module under development aims to increase efficiency and reduce power loss that happens from heating and exposure to different spectra of light. The new design concepts would not create additional costs for the modules and will significantly increase the operational efficiency of CPV modules by 3-4% and enable CPV systems to approach a levelized cost of energy of $0.06 per kilowatt hour.

APPROACH

The research team will incorporate luminescent coupling effects and radiative cooling layers into the module to reduce power loss. These two concepts focus on optical engineering within the solar cell, an area that has been largely ignored in prior CPV cell design. Researchers plan to demonstrate the validity and effectiveness of their approach through outdoor testing at the National Renewable Energy Laboratory.

INNOVATION

This project is focusing on materials designs that compensate for the usual energy losses caused by daily and seasonal spectral variations and maintain significantly higher average electrical output. In addition, due to the highly concentrated sunlight that reaches CPV cells, their temperature is often 40-80°C above the ambient temperature, resulting in lower efficiency. Applying radiative cooling materials and photonic crystal nanostructures to the solar cell significantly increases the radiative loss and lowers cell temperature by 10-20°C compared to traditional heat sinks. If successful, this project will reach a world record in multi-junction solar cell performance and CPV module efficiency under real operating conditions.