IBM is taking new steps to make greener energy generation more common. The company has unveiled plans to create more efficient and less expensive solar cell systems. It will work with Japan-based Tokyo Ohka Kogyo to build what it calls the “next generation” of CIGS — or Copper-Indium-Gallium-Selenide — solar cell modules.
The modules will use thin film — layers of material as thin as a single nanometer in width — to harness energy from the sun. It’s a new twist on a process already deep in development.
Breaking the Barrier
Current thin film systems convert only six to 12 percent of the sun’s rays into energy. The new IBM-TOK technology will double some of those efficiencies, with rates reaching 15 percent or higher. That, the companies believe, may break the cost barrier currently keeping the technology from becoming mainstream.
The new systems will also be a full 100 times thinner in size than many current models. That means users will be able to easily install them on windows or building surfaces.
Right now, most thin film solar technology is being used in Germany and other European nations — even though much of it is produced in the United States.
“It’s because of the progressive subsidies there,” Dr. Rob Collins, professor of physics at the University of Toledo, told TechNewsWorld.
Upcoming policy changes, however, could help convince American companies to rethink their stances.
“Many states are implementing renewable portfolio standards,” Collins said. “Those basically mandate the use of solar energy and say the utility generation of power has to include some renewable component with a timescale and a penalty for noncompliance. We believe this type of technology will gain acceptance in the U.S. as a result.”
The thin film sits on glass modules that are essentially the gateway to cleaner electricity. They allow generation without the emissions found in standard nuclear, coal and oil systems.
The thin film does its work by absorbing different ranges of the solar spectrum into different semiconductor layers. From there, electrons are separated and turned into power that can be put to immediate use.
“When the light is absorbed, it creates a free electron in the hole,” Collins explained. “The built-in electric field in the device separates the electron and the hole, and they diffuse to the context where they can power an electric circuit.”
Another perk, Collins said, is the systems’ ability to align solar output with a community’s usage pattern.
“By using solar, you don’t need to hit the high peaks where the electric power is the most expensive,” he said. “It’s probably the strongest driver for this.”