If you follow solar news, chances are you’ve heard of Dow Chemical’s solar shingles (s dow) — a more aesthetic way to put panels on rooftops. Well, according to founder and CEO of thin-film solar startup NuvoSun, Dave Pearce, NuvoSun is the latest producer of Dow’s solar shingles and the company is scaling up a 40 MW production line to meet Dow’s demand. Pearce tells us the company also hopes to raise some $50 million for factory expansion that could take place in China.
NuvoSun, founded in 2008, has been pretty quiet about what it’s been up to since announcing in Sept. 2010 it was moving into a new headquarters in Milpitas, Calif. The company makes thin-film solar panels using copper, indium, gallium and selenium (CIGS), the same materials used by a number of high-profile solar startups such as Nanosolar, MiaSole, SoloPower and Stion.
It’s also the kind of technology that has bedeviled bright engineers and managers, because many of these startups have taken a lot longer to complete technology development and reach mass production. Pearce was MiaSole’s founder and CEO and left in 2007, and he’s conceded that he, too, underestimated the amount of time it would take to reach commercial production at MiaSole. He remains a MiaSole shareholder.
The lone CIGS “success” story seems to be Solar Frontier, which is part of energy giant Showa Shell and began producing its CIGS solar panels from a new 900 MW factory last year. It’s set to supply up to 150 MW of panels for a project in California. We actually don’t know how successful Solar Frontier is – the company doesn’t divulge its production costs or profits, and it brought online that huge factory at a time when the market had a glut of solar panels and many manufacturers were reducing production or closing factories.
Spend less to do more
So how do you build a new company like NuvoSun at times like this? The answer, not surprisingly, is to keep costs low. Pearce said he’s been able to design and start running that first 40 MW commercial production line by raising a total of $47 million in equity and convertible notes.
“Our capital expenditure is dramatically lower than our competition. Most companies spend way more than $47 million just on their production line,” Pearce said.
When NuvoSun designed its pilot production equipment, Pearce says it kept in mind that the equipment has to closely resemble what it envisioned the production equipment would look. That wasn’t the case at MiaSole, which required a lot of changes to the production equipment and process, he said, so he’s learned that lesson.
NuvoSun has a team of engineers in Shanghai for designing its production equipment. It’s the team that existed at MiaSole and was let go by Pearce’s successor. Pearce said he folded that team into NuvoSun in 2008 to work on a new CIGS thin-film manufacturing process. He said developing and building factory equipment is cheaper in China, where the 40 MW production line came from.
The Dow connection
NuvoSun’s technology deposits the CIGS materials on stainless steel foil. After adding all other layers to the thin films, such as the transparent conductive oxide, the films are cut into reels of cells. Here is where copper ribbons are partially laminated onto the top of the cells to form the metal contact lines for transporting electricity produced by the cells. After that, factory tools cut the reels into cells, test their performance, then connect them into strings, Pearce said.
NuvoSun will ship the CIGS strings to Dow, which will then assemble them into shingles that are topped by glass (the bottom is made of a polymeric material). Dow is also working with other CIGS suppliers like Global Solar.
NuvoSun also plans to make solar panels of 0.7-meter by 1.4 meter, which would include 4 strings of 12 cells each. The company is making cells with 10- to 12-percent efficiency, Pearce said.
The company doesn’t yet have the equipment for some of the final assembly steps for making panels, such as encasing the cells between glass and adding other components such as the junction box. It’s outsourcing that part of the work out right now since it’s not producing products in high volumes.
The startup’s pilot line uses a 13-inch wide foil, but the 40 MW commercial line is using a 1-meter wide foil. NuvoSun is still doing test-runs of its factory equipment to make sure it can produce cells and strings of desired performance and can mass-produce them. The plan is to reach that mass-production mode this year and start delivering to Dow, Pearce said.
Although the company doesn’t plan to add more production capacity soon, given the solar market still has more supply than demand, it’s thinking about where that next factory might be. China is a likely location, because it can offer lower-cost manufacturing and a large market, Pearce said. He’s looking at maybe building a 200-400MW factory in central China.
The company has 56 employees, including five temporary staffers, in Milpitas and 40 in Shanghai.
Photos courtesy of NuvoSun