Full Spectrum Solar Energy Conversion

Conventional solar energy conversion techniques have seen tremendous success in recent years, with photovoltaics experiencing significant market penetration in locations across the world. However, these modules typically convert no more than 20% of incoming solar energy into electricity, due in large part to inefficient utilization of the entire solar spectrum. Our group is exploring alternative solar energy harvesting schemes that seek to maximize the use of every wavelength in the solar spectrum, enabling significant increases in efficiency with potential for lower cost.

To do this, we are pursuing an approach that utilizes hybrid solar energy conversion, generating electricity from high efficiency multi-junction cells in combination with the capture of sunlight as thermal energy. Our innovative receiver technologies keep the solar cells below 100°C while generating thermal energy in the form of pressurized hot water at temperatures up to 250°C. The thermal energy can then be stored until the energy is needed. The stored energy can be converted to electricity or may be used directly to provide process heat for a wide range of commercial and industrial users.

Initially funded by DOE’s ARPA-E and in partnership with the University of San Diego, San Diego State University, Boeing-Spectrolab, and Otherlab, the project demonstrated field-validated prototype systems with >85% energy conversion efficiency in a modular and scalable form-factor. Current collaborators include the University of San Diego and Bernhard. Our latest technology generation, the Sunflower Receiver, is pushing towards lower cost and higher durability, while maintaining high efficiency cogeneration of electricity and process heat. This technology has been field tested in San Diego and is now being deployed on a building at Tulane to further advance the technology and demonstrate its effectiveness with a pilot customer.

“Our group is exploring alternative solar energy harvesting schemes that seek to maximize the use of every color in the full solar spectrum, enabling significant increases in efficiency with potential for lower cost.”