Thinner, better, already sold out—the new new thing in solar?

Solar energy can seem like a green tech fantasy. Energy free for the collection.
Written by Harry Fuller, Contributor

Solar energy can seem like a green tech fantasy. Energy free for the collection. Found in some of the emptiest spots on earth: deserts, parking lots, urban rooftops, open ocean, airplace wings, at 50,000 feet above the earth. Think about all that sunshine. And a company down in Tucson thinks it's got a handle on the best way discovered so far to convert some of that sunshine into electricity. The current dominant tech requires heavy silicon crystal converters, the familiar solar panel.

Flexible solar collector, courtesy Global Solar.

Now Global Solar Energy is a major producer of thin-film photovoltaic Copper Indium Gallium DiSelenide (CIGS) solar cells, an alternative to the older solar panel technology. Among solar converter units CIGS has the lightest weight per kilowatt, says Global Solar's CTO, Dr. Jeff Britt. I spoke with him recently, and he explained that Global's just beginning to produce their thin film strings at a new, expanded plant in Tucson. And they're already sold out for all they can produce this year. Most of the expected product for 2009 has been spoken for. Remind you of when the iPod launched?

Dr. Britt said the basic materials needed for their thin solar film is more expensive per pound than the material in traditional solar panels. Those traditilonal panels are 100-200 micrometers thick while Global produces more efficient conversion materials with 1-2 micrometers. That nmeans much less material is needed, less weight, and ...get this: the ability to attach the thin film to metallic foil that is flexible. Dr. Britt said the key to expansion of use and application for their CIGS solar cells is: the coating. That's right: the polymers that protect the CIGS from water and other potentially destructive elements. Global is right now working with polymer pros and building materials makers to creat solar roofing that lasts twenty years. We could never trap all the hot air, but imagine if we could at least put the U.S. Capital and White House to work producing electricity?


Global Solar is owned by two German firms. That's Solon AG and I-sol Ventures. I-sol is a German venture firm that specializes in alternative energy investments. Since the company was bought last year, expansion has been the goal. A second plant is planned now for Berlin, the home town of the new owners. Germany is a major center of solar production and use. You may recall the German entry won the Solar Decathlon last fall. Global is NOT a consumer company. They'll make the thin film solar string and sell it to manufacturers for various building, industrialand consumer uses. Dr. Britt says their product is already catching the ye of numerous outdoors equipment firms. I asked how soon we'll have solar covering on all our cars and buses? We agreed it can't happen soon enough.

Interesting back story: Global was originally started by the local utlitiy company in Tucson. Dr. Britt tells me a local political leader desribes Arizona as the Saudi Arabia of solar power. There is certainly plenty of sun energy there as this NASA map shows.

The product has a dozen countries already using it for military apps. Can you imagine anybody wanting to use solar collectors in the desert? Global's thin film photovoltaics all meet the specs of the U.S. Defense Department for portable solar units.

Where does the raw material come from? Copper is readly available on the global market. Canada produces selenium. Indium is the most precious material used in CIGS and is a by-product of zinc mining in China.


Here's a link to the NREL webpage describing the early research that led to CIGS. The development of thin film, flexible tech was given a research award back in the solar dark ages, 2004.

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