Engineers have developed a new hybrid solar converter that uses the sun’s energy to make electricity and steam,media reported. The device is reported to be highly efficient and low in operation, allowing industry to make more widely use of solar energy. The most common way to collect energy from the sun is through photovoltaic power generation. These solar cells generate electricity from the sun, and they are so simple that they are built into everything from garden lights to the grid itself.
But that’s not the only way. Solar concentrators collect heat rather than light, pool sunlight to heat the liquid it contains, and then use it to generate electricity — for example, as a steam-turning turbine — or more directly to heat homes or other industrial processes. Usually the two systems are separate, but attempts have been made to pair them into a single hybrid device, often resulting in lower efficiency or higher costs. But now, researchers claim to have created a new hybrid solar converter that mixes the benefits of the two devices.
The device looks like a satellite antenna, with a small device hanging from the center of the parabolic collector. The disc part is mirrored and the sunlight is focused on the box in the middle. The bottom of this section is equipped with a multi-junction solar cell that collects visible and ultraviolet light and converts it into electrical energy. But the smart part is that these batteries redirect infrared light — that is, thermal energy — to a separate thermal receiver higher in the device. The receiver is basically a cup-shaped cavity surrounded by pressurized water that captures heat and turns it into steam.
The team says the overall collection efficiency is 85.1 percent, which means a very large amount of solar energy is converted into electricity or heat. Steam can be heated to 248 degrees C (478 degrees F), which is much higher than many other thermal collectors. This means that it is warm enough for many industrial processes, such as drying, curing, disinfection and pasteurization.
Another advantage is cost. Once scaled up, the hybrid unit could cost as little as 3 cents per kilowatt hour, the team reported.
The team, made up of researchers from Tulane University, the University of San Diego, San Diego State University, Boeing Spectrum Lab and Otherlab, has secured follow-up funding for the next round of development and plans to refine the technology and work to scale up pilot plant tests.
The study was published in the journal Cell Reports Physical Science.