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21 April 2009


BioSolar expands BioBacksheet range to thin-film PVs

BioSolar Inc of Santa Clarita, CA, USA says that it is nearing completion of the commercialization of its BioBacksheet product and is entering the pre-production stage on new versions to address the entire flat solar panel market.

Backsheets (the bottom-most layer of nearly all photovoltaic solar cell modules) are currently made from petroleum and designed to protect the solar cell from environmental hazards such as moisture and ultraviolet (UV) rays. BioSolar’s BioBacksheet is a protective covering made from renewable plant sources (a cellulosic film combined with a highly water resistant and high-dielectric-strength nylon film made from castor beans). It is expected to cost substantially less than traditional petroleum-based backsheets.

“Contrary to common belief, commercialization of renewable energy technologies such as BioSolar’s BioBacksheet is quite complex and requires both a comprehensive understanding and analysis of its potential, as well as the development of innovative models to help it gain market penetration,” says chairman & CEO Dr David Lee.

“We continue our mission to develop new products that utilize our proprietary manufacturing and materials process to enhance the characteristics of traditional bio-based materials and turn them into robust and durable materials for solar applications,” he adds.

Currently, the firm’s patent-pending BioBacksheet technology for crystalline silicon (C-Si) photovoltaic solar cells is in the pre-production phase. “The C-Si area is the largest photovoltaic market segment,” says Lee. “However, at BioSolar we recognize that the low-cost potential of thin-film modules, particularly CIGS (copper indium gallium diselenide) and CdTe (cadmium telluride), are emerging as formidable competitors in the global solar market and attracting gigantic investments,” he adds.

In a report ‘PV Technology, Production and Cost, 2009 Forecast’, Greentech Media analysts report that, by 2012, CdTe and CIGS could comprise nearly 1.5GW and 3GW (6% and 12% of the global supply of solar panels), respectively.

“These products require a backsheet comprising an almost perfect moisture barrier,” says Levy. “Currently, glass is the material of choice. It works, but it is heavy and expensive,” he adds. “In response, we have started development on a BioBacksheet with the required barrier properties for this application. It is a composite film consisting of bio-based and 100% recyclable materials,” he explains. 

The resulting product is expected to be much lighter than glass as well as lower cost. “The greatest impediment to solar replacing fossil fuels is cost. Manufacturers struggling to make these technologies cost-effective are increasingly looking to various material choices,” says Lee.

In addition, many of these thin-film PV manufacturers have expressed strong interests for a ‘green’ backsheet to be incorporated into their thin-film solar panels, says Lee. “Solar power produces clean energy, but in order for it to be considered truly sustainable, we need to ensure we are environmentally sensitive in the production and disposal process as well.”  

BioSolar is therefore expanding its BioBacksheet technology to accommodate copper indium gallium diselenide (CIGS) and cadmium telluride (CdTe) thin-film photovoltaic modules.

“Two BioSolar products are currently in the pre-production stage and nearing qualification for full production,” says Lee. “The BioBackSheet-L, an enhanced performance backsheet for demanding PV applications, is nearing qualification for production, and the BioBackSheet-C, designed for cost-sensitive, economical PV modules, is making excellent progress in pre-production development and testing,” he adds.

“BioBackSheet-A with ‘Absolute Moisture Barrier’ is also doing well in the late R&D stage,” says chief technology officer Dr Stanley Levy. “We will continue to provide more information in the future as the product continues to evolve.”

*BioSolar exhibited its BioBacksheet technology at the International Green Energy Expo at the Daegu Exhibition & Convention Center in Korea (8-10 April). 

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