Major development in solar power rooftop energy source

Flexible rooftop solar panels, called building-integrated photo-voltaics (BIPVs), could replace today’s boxy solar panels that are made with rigid glass or silicon and mounted on thick metal frames. The flexible solar shingles would be less expensive to install than current panels and made to last 25 years.

“Flexible solar panels could easily become integrated into the architecture of commercial buildings and homes,” said Mark Gross, Senior Scientist at the US Department of Energy's Pacific Northwest National Laboratory (PNNL). “Solar panels have had limited success because they've been difficult and expensive to install.”

Researchers at PNNL will create these flexible panels by adapting a film-encapsulation process currently used to coat flat panel displays that use organic LEDs (OLEDs). The work is made possible by a Cooperative Research and Development Agreement recently penned between Vitex Systems and Battelle — the world's largest non-profit independent research and development organisation — which operates PNNL for the US government.

PNNL researchers developed the thin film technology in the 1990s for a number of possible applications, including solar power. Vitex licensed the technology and focused its initial efforts on developing the ultra-barrier films for flat-panel displays. Now PNNL and Vitex are taking a hard look at solar power.

The encapsulation process and the ultra-barrier film, called Barix Encapsulation and Barix Barrier Film, respectively, are already proven moisture barriers. But researchers need to find a way to apply the technology to solar panels that are made with copper indium gallium selenide or cadmium telluride.

Under the agreement, researchers will create low-cost flexible barrier films and evaluate substrate materials for solar panels, which are also called photo-voltaics. Both the film and substrate must be able to survive harsh ultraviolet rays and natural elements like rain and hail for 25 years.

The agreement also calls for researchers to develop a manufacturing process for the flexible panels that can be readily adapted to large-scale production. If successful, this process will reduce solar panel manufacturing costs to less than US$1 per W of power, which would be competitive with the 10 cents per kWh that a utility would charge.

Battelle's Chief Financial Officer, Martin Inglis, is optimistic that this research agreement will contribute to a new way of generating solar power, stating: “We're confident that Vitex will be uniquely positioned to help meet the demand for flexible solar panels, OLED displays and lighting that should rise, along with the economy.”