Hybrid Solar Converter with Light-Filtering Mirror
There are two primary methods for capturing and using sunlight today: direct conversion of sunlight to electricity using photovoltaic (PV) solar panels, or focusing sunlight onto a fluid that is used to drive a steam turbine in concentrated solar power (CSP) systems. Storing hot fluid in CSP systems is a less expensive way to generate electricity when the sun is not shining compared to storing electrical energy from PV in batteries. However, PV uses just part of the solar spectrum at high efficiency, while CSP systems use the entire solar spectrum but at low efficiency. Combining the best elements of these two technologies could provide a means to get the most out of the full solar spectrum, generating both electricity and storable heat (for later use) within the same system. Developing hybrid solar energy systems that perform both functions at the same time could provide electricity at cost comparable to traditional sources, whether the sun is shining or not.
Project Innovation + Advantages:
Cogenra Solar is developing a hybrid solar converter with a specialized light-filtering mirror that splits sunlight by wavelength, allowing part of the sunlight spectrum to be converted directly to electricity with photovoltaics (PV), while the rest is captured and stored as heat. By integrating a light-filtering mirror that passes the visible part of the spectrum to a PV cell, the system captures and converts as much as possible of the photons into high-value electricity and concentrates the remaining light onto a thermal fluid, which can be stored and be used as needed. Cogenra’s hybrid solar energy system also captures waste heat from the solar cells, providing an additional source of low-temperature heat. This hybrid converter could make more efficient use of the full solar spectrum and can provide inexpensive solar power on demand.
If successful, Cogenra’s hybrid solar energy converter can utilize the full solar spectrum more efficiently than today’s PV and CSP systems could independently.
Developing new hybrid solar systems that produce electricity and heat could facilitate the dispatch of domestically-sourced power at costs comparable to traditional sources, whether the sun is shining or not.
Replacing energy systems powered by fossil fuels would provide an immediate decrease in greenhouse gas emissions, 40% of which come from electricity generation today.
Cost-effective, dispatchable solar energy alternatives would stabilize electricity rates for consumers as the penetration of renewable energy increases in the coming years.