HelioVolt said Nov. 10 that it is extending its collaborative research agreement with the National Renewable Energy Laboratory (NREL) as it moves toward commercial production of its new copper indium gallium selenide (CIGS) photovoltaic panels.
The research is geared toward developing cheaper methods of producing the modules, explained Iga Hallberg, vice president of business development and marketing for the company.
The Cooperative Research and Development Agreement with NREL, she explained, is for developing a method of depositing the CIGS materials in normal atmosphere conditions.
“Today, the conventional method [of depositing thin-film materials] is using vacuum-based technologies, and clearly a lot of us are looking into liquid-based technologies,” she said. “We’re working with NREL to deposit liquid nano particles at micron thick levels; the [solar] absorber layer is about a micron-and-a-half thick,” for HelioVolt’s PV systems.
HelioVolt Founder and Chairman BJ Stanbery said in a press release that “we believe that high conversion efficiencies—above 15 percent on a full size monolithically interconnected module rather than cell level—require developing innovative methods for producing nanoscale building blocks and synthesizing them into device-quality CIGS thin-film material.”
Many photovoltaic modules use a series of smaller cells or wafers connected together to create solar modules, according to Hallberg. She added that companies often base their efficiency figures on the output of individual cells rather than the module’s full efficiency.
“We believe you lose a lot of efficiency when you connect all those together,” she said. “It’s much more difficult to do monolithic integration on a large area.”
But using monolithic integration allows the company to reduce additional hardware on the modules without impacting their generating capacity.
“We haven’t actually disclosed the efficiency numbers,” she said. “There’s a specific protocol we have to go through with NREL and those numbers have not been released.”
She added that the modules still have to go through some validation before they can be rated for efficiency.
HelioVolt’s modules will likely start becoming available next early year and are intended for the commercial rooftop market, like box store and warehouse rooftops, she said.
“We’re in the process of the final scale-up in our facility in Austin and plan to start [UL]certification by the end of the year,” Hallberg said.
Pictured: HelioVolt's factory floor.