Solyndra broke its silence to discuss its thin-film solar technology Monday night, claiming that its product is cheaper to install and more effective at converting sunlight into electricity than conventional solar panels.

Solyndra rolls its copper-indium-gallium-diselenide (CIGS) thin films into a glass cylinder and places 40 of them in each 1-meter-by-2-meter panel. The design is unusual. Other companies' cells, including thin-film and conventional silicon cells, are flat.

The Fremont, Calif.-based startup began shipping its panels to customers in large volumes in July, CEO Chris Gronet said. He wouldn't disclose how much the company is producing in "large volumes" or when it would fully ramp its production.

But the startup has announced contracts with two customers so far, Solar Power Inc. and Phoenix Solar, and it expects to ink more contracts "very soon," he said.

Solyndra has a $325 million deal to deliver panels to Solar Power from 2008 to 2012. Phoenix Solar's deal, for the same delivery period, is worth about €450 million ($546 million).

Gronet says the company's panels can capture direct, indirect and reflected light, making them more productive than many other solar panels today. The company is targeting the commercial rooftop market, and is marketing its systems both to installers and directly to business customers.

Each Solyndra cylinder, which is one inch in diameter, is made up of two tubes. The company uses equipment it has developed to deposit CIGS on the outside of the inner tube, which includes up to 150 CIGS cells. On top of the CIGS material, it adds an "optical coupling agent," which concentrates the sunlight that shines through the outer tube, Gronet said. He declined to disclose the materials for the coupling agent.

Gronet said his company can produce thin films that are roughly two times thinner than some of the CIGS cells that have been verified by the U.S. National Renewable Energy Laboratory, which tests and validates solar technologies.

The cells that Solyndra is making in high-volume production can convert 12 percent to 14 percent of sunlight into electricity, an efficiency that Gronet said is better than competing CIGS thin-film technologies.

Global Solar said earlier this year that its CIGS cells from its factory had reached an average efficiency of 10 percent (see Q&A: Global Solar VPs Dish Thin-Film Details).

Other companies have released higher efficiency numbers, but achieved those in labs or in lower-volume production. Efficiency numbers reached in labs tend to be higher than what can be achieved during regular production.

HelioVolt Corp. in May said it had produced CIGS cells with efficiency as high as 12.2 percent on a pilot line (see HelioVolt Hits 12.2% Efficiency).

And Nanosolar said it has created tools that can produce CIGS cells with a 14.5 percent efficiency, but wouldn't say whether the figure applied to cells actually being produced (see Nanosolar Creates Largest Thin-Film Tool).

Gronet declined to disclose the cost of producing Solyndra's cells or panels.

After inserting the inner tube into the outer tube, each cylinder is sealed with glass and metal to keep out moisture, which erodes CIGS' performance. Gronet declined to say what metal is used for the seal, but hinted that the sealing technology is commonly used in florescent bulbs.

Each cylinder is placed one inch apart and connected at each end with wiring and harnesses that lie parallel to the cylinders. The design is intended to keep broken cylinders from affecting the performance of those that still work.

Solyndra then fits the cylinders into aluminum-framed panels, which are placed on a white mounting device a foot off the roof. The clearing allows the CIGS tubes to capture sunlight reflected from the rooftop.

Unlike many conventional solar-power installations, which have to be tilted to better capture sunlight, Solyndra's system doesn't need to be anchored on the roof with ballasts and adhesives, Gronet said. The cylindrical design makes the panels more wind resistant, capable of withstanding winds of up to 130 miles per hour, he said.

"Because there are gaps in our panels, there is no lift when the wind blows through. You can set the panels on the roof like a coffee table," Gronet said.

Solyndra's press release included a testimony from Phoenix Solar's chief technical officer, Manfred Bachler, who said Solyndra's panels cost 50 percent less – and one-third of the time – to install.

The company has developed its own manufacturing equipment and can build a production line in six months, Gronet said.

Solyndra operates in a 300,000-square-foot complex made up of three buildings. The company makes its inner tubes in a 183,000-square-foot building at its headquarters in Fremont, where a second, 20,000-square-foot building serves as office space. A third building, located in nearby Milpitas, assembles the cylinders into panels.

The company is increasing its production output to reach the 110-megawatt capacity at the inner-tube factory, which will allow Solyndra to roll out two million cylinders per year.

Solyndra also is looking to build a second, 420-megawatt factory on the same street in Fremont (see Solyndra Plans Huge Thin-Film Factory). Gronet declined to say how much the company expects to spend to build the factory.

The company has raised about $600 million in equity from investors since its inception in 2005, according to Gronet, who declined to discuss whether the company is seeking more money. He also declined to comment on a Green Light post that reported the company didn't reach a $350 million fund-raising goal this summer.

Investors include Virgin Green Fund, Madrone Capital Partners, RockPort Capital Partners, Argonaut Private Equity, Masdar, Redpoint Ventures, U.S. Venture Partners, Artis Capital Management and CMEA Ventures. 

Tags: cells, cigs, cylinder, roof, solar, solyndra, thinfilm