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University of Arizona is developing a hybrid solar converter that splits the light spectrum, sending a band of the solar spectrum to solar cells to generate electricity and the rest to a thermal fluid to be stored as heat. The team's converter builds off the CSP trough concentrator design, integrating a partially transmitting mirror near the focus to reflect visible wavelengths of light onto high-efficiency solar cells while passing ultraviolet and most infrared light to heat a thermal fluid.

Tulane University and its partners are developing a hybrid solar energy system capable of capturing, storing, and dispatching solar energy. The system will collect sunlight using a dual-axis tracker with concentrator dish that focuses sunlight onto a hybrid solar energy receiver. Ultraviolet and visible light is collected in very high efficiency solar cells with approximately half of this part of the spectrum converted to electricity.

Yale University is developing a dual-junction solar cell that can operate efficiently at temperatures above 400 °C, unlike today’s solar cells, which lose efficiency rapidly above 100°C and are likely to fail at high temperatures over time. Yale’s specialized dual-junction design will allow the cell to extract significantly more energy from the sun at high temperature than today’s cells, enabling the next generation of hybrid solar converters to deliver much higher quantities of electricity and highly useful dispatchable heat.

Arizona State University (ASU) is developing a hybrid solar energy system that modifies a CSP trough design, replacing the curved mirror with solar cells that collect both direct and diffuse rays of a portion of sunlight while reflecting the rest of the direct sunlight to a thermal absorber to generate heat. Electricity from the solar cells can be used immediately while the heat can be stored for later use. Today’s CSP systems offer low overall efficiency because they collect only direct sunlight, or the light that comes in a straight beam from the sun.

Massachusetts Institute of Technology (MIT) is developing a high-efficiency solar cell grown on a low-cost silicon wafer, which incorporates a micro-scale heat management system. The team will employ a novel fabrication process to ensure compatibility between the indium gallium phosphide (InGaP) solar cell and an inexpensive silicon wafer template, which will reduce cell costs. MIT will also develop a color-selective filter, designed to split incoming concentrated sunlight into two components.

Massachusetts Institute of Technology (MIT) is developing a hybrid solar converter that integrates a thermal absorber and solar cells into a layered stack, allowing some portions of sunlight to be converted directly to electricity and the rest to be stored as heat for conversion when needed most. MIT’s design focuses concentrated sunlight onto metal fins coated with layers that reflect a portion of the sunlight while absorbing the rest. The absorbed light is converted to heat and stored in a thermal fluid for conversion to mechanical energy by a heat engine.

Arizona State University (ASU) is developing a solar cell that can maintain efficient operation at temperatures above 400°C. Like many other electronics, solar panels work best in cooler environments. As the temperature of traditional solar cells increases beyond 100°C, the energy output decreases markedly and components are more prone to failure. ASU’s technology adapts semiconducting materials used in today’s light-emitting diode (LED) industry to enable efficient, long-term high-temperature operation.

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.