IBM Solar Energy Tech Claims to Harness Power of 2,000 Suns
IBM is working on an affordable photovoltaic system capable of concentrating solar radiation 2,000 times and converting 80% of the incoming radiation into useful energy.
Mon, February 24, 2014
A byproduct of the system is that it also produces a massive amount of heat. That heat can be harvested to perform other functions, such as desalinating water and creating cool air in sunny, remote locations where they are often in short supply, the IBM researchers said.
The High Concentration PhotoVoltaic Thermal (HCPVT) system can convert 80% of the incoming solar radiation into useful energy.
Bruno Michel, a research scientist with IBM Research, Zurich, points to the HCPVT solar conversion system.
If IBM's claims prove true, its solar concentrator would surpass a recently achieved world record for solar conversion efficiency, which is 44.7%. That system, created by a team of scientists from the Fraunhofer Institute for Solar Energy Systems along with others, was able to concentrate power that is the equivalent of 297 suns.
The HCPVT system uses a big mirror that looks like a satellite dish to concentrate sunlight onto a small semiconductor chip, which then converts that light into energy. Because of the high concentration, along with energy, heat is also concentrated and must be dissipated so it doesn't melt the system. That heat can be used for other processes, such as desalination (evaporating saltwater to make potable water), according to Bruno Michel, a lead scientist with IBM Research, Zurich.
"The Sun is the [source of the] most abundant energy we have. We get 85,000 terawatts of energy [from the Sun] on the face of the globe, and we only need 15 terawatts," Michel said. "So we only need a fraction of .3 or .4% of the surface of the earth in order to provide all our energy.
"So we could build a solar power station in unused land in the Sahara, for example, to provide enough energy in the long term to replace all of the fossil and nuclear energy," he added in a video describing the technology.
The prototype HCPVT system includes a Sun tracking system that positions the dish at the best angle to capture the sun's rays. The mirror reflects onto several microchannel-liquid cooled receivers with triple junction photovoltaic chips -- each .39-in. x .39-in. chip can convert 50 watts, on average, over a typical eight-hour day in a sunny region.
The entire receiver combines hundreds of the chips and provides 25 kilowatts of electrical power. The photovoltaic chips are mounted on micro-structured layers that pipe liquid coolants within a few tens of micrometers off the chip to absorb the heat and draw it away. The system is 10 times more effective than passive air cooling.