Solar Cells Info

Jan 21, 2008
Source: FabTech.org
http://www.fabtech.org/content/view/6001/

Although they both participate in the emerging copper indium gallium (di)selenide (CIGS) thin-film photovoltaics sector, Ascent Solar Technology and International Solar Electric Technology (ISET) have at least as many differences between them as things in common. Ascent’s PV roots go back to work begun at ITN Energy Systems in the early 1990s, while ISET first hung out its shingle in March 1985. ITN created Ascent in 2005, and the new venture has been publicly traded since 2006, while ISET has been and remains fiercely independent. Ascent’s process technology uses vacuum-based coevaporation and sputtering, yet ISET favors a nonvacuum ink-print/selenization approach. Both use molybdenum for back contacts and zinc oxide for their front contacts, although ISET adds ITO to the front. ISET’s current manufacturing strategy employs batch processing on glass, while Ascent pursues a roll-to-roll production scheme, with flexible plastic as its substrate of choice. Ascent is based in Littleton, Colorado; ISET calls Chatsworth home, in L.A.’s San Fernando Valley.

Ascent and ISET do share one common value: they passionately believe in the enormous potential and importance of solar power and thin-film CIGS’ place in the promised PV land of <$1-per-watt grid-parity cost. Neither company has sought the media publicity spotlight, unlike Nanosolar, HelioVolt, and other CIGS peers, so they've been left out of many discussions and coverage of the thin-film PV arena. But that doesn't seem to bother either company too much (well, maybe a little). "Until you're producing product that shows viability on the commercial scale, you don't have anything," said Brian Blackman, Ascent's director of investor relations. ISET's head honcho Vijay Kapur, a 33-year-plus PV veteran and outspoken champion of solar energy, put it this way: "This kind of serious business can't be done on hype.... I'll make noise at the appropriate time. When we move product, you'll hear about me." "There's lots of misunderstanding and confusion out there, so we try and be as transparent as possible," explained Blackman. "It's all about keeping the transparency open going forward, whether it's favorable or not." This commitment to openness, although not all-encompassing (he wouldn't divulge certain particulars of Ascent's film stack, for example), still shows up in the level of manufacturing and process granularity that the company provides in its latest SEC 10-Q statement, a far cry from the paucity of information offered by DayStar in its filings or most privately held CIGS companies. A read-through of Ascent's SEC filing (filed after the end of 3Q07), especially the several pages in the section titled "Management's Discussion and Analysis or Plan of Operation," reveals a fair amount of specifics around the company's goal of being "the first company to manufacture large, monolithically integrated roll format PV modules in commercial quantities that use a highly efficient thin-film copper-indium-gallium-diselenide absorbing layer on a flexible high-temperature plastic substrate." When/if Ascent perfects its monolithic-integration module manufacturing approach ("monolithic" as in individual cells do not have to be connected manually), not only will the PV rolls coming off the line "be identical for every market, but multiple modules can be printed on each roll to serve a multitude of applications," according to a company investor presentation. Blackman told me that "there have been no changes to our stated progress," with all equipment delivered and installed in Ascent's pilot facility. "We're running one process at a time at this point." Using roll-to-roll rapid prototyping (with 100-ft-long plastic rolls) and material flow techniques developed in 2006, the team is working to qualify and integrate the line and have it operational by the end of 1Q08. The second quarter will be spent optimizing the toolset and achieving a low-rate production flow and therefore moving closer to Ascent's primary near-term objective: to "enable an increase in manufacturing yield and module efficiencies to support full-scale manufacturing at the 1.5 MW level," according to the document. If the initial milestones are met, the IR director "expects to see nominal revenues in 2008." "Performance on the pilot production line should prove out the manufacturing processes and product certification, and provide product to support market development that should enable us to transition into large full-scale, commercial manufacturing of our CIGS PV products," Ascent's 10-Q states. "Scale-up to the 100-MW level and beyond will first involve the successful deployment of the 1.5-MW production line in 2008, followed by a planned scale-up to a 25-MW production line in 2009. The 25-MW scale production line is envisioned to become our manufacturing template for large-scale commercial production. Increasing production to 100 MW and beyond will then involve deployment of multiple 25-MW production lines." Blackman described the envisioned modular 25-MW lines as "comparable to a cookie cutter," which can be rapidly scaled up to a 100-MW-capacity facility, the first of which will be built "somewhere in Colorado." In addition to dialing in process variables, ramping to high yields, and driving up module conversion efficiencies from the current 8% to over 10%, the company says the biggest challenge will be transitioning to one-third-meter-wide plastic rolls for the 1.5-MW line and then to one-meter-wide rolls when the line is scaled up to 25 MW. With significant know-how and investment from ITN and use of its R&D lab, the company plans to develop a prototype CIGS deposition tool that can handle the meter-wide material and allow the rapid evaluation and testing of the larger-area deposition sources and process control system is also part of Ascent's 2008 gameplan, in preparation for its 25-MW line integration by the end of 2009, according to company documents. Ascent's plans may seem quite cautious, but Janco Partners' Vijay Singh, in his recent report on the company, supports the approach. "While this may appear painfully conservative, we believe the growth roadmap is prudent considering the early stage of the technology development and should help the company avoid making more expensive mistakes during the commercial production stage." DSC_0244Brise_Soleil.jpg The Brise Soleil shading devices (in development), which integrates the Hydro Building aluminum systems with Ascent's flexible CIGS modules. (Photo courtesy of Ascent) The investment researcher also praises Ascent for its strategic partnerships alliances. "Strong partnerships---Ascent's alliances with ITN Energy (founding partner) and Norsk Hydro (strategic investor own)---are significant competitive advantages. Ascent has exclusive access to ITN's proprietary process and control technologies utilized in the production of CIGS PV module," what Blackman calls the "secret sauce." "With a significant presence in the global building systems market," Singh continues, "Norsk is likely to be an important distribution partner." Hydro, which owns nearly a quarter of Ascent's stock, will provide channel access for the start-up's flexible products to the gonna-be-huge building-integrated PV market. A supportive founding company and huge multinational corporate investor may not be part of the story at ISET, but when cofounder/president/CEO Vijay Kapur claims that "the genesis of CIGS took place in his company," he's not really exaggerating. From his time at Stanford Research Institute and Arco Solar to the first two decades of ISET's existence, he and his collaborators have been involved in much of the groundbreaking R&D in various PV areas, especially CIS/CIGS. "We developed hundreds of new technologies, many of which are used today," according to Kapur. Ex-ISETers are scattered through the ranks of companies such as Nanosolar, Solopower, Showa, and Honda Soltec. After griping about the lack of recognition of ISET, "that for more than 22 years has been working on CIGS all along," Kapur then pointed the finger directly at Nanosolar, a company with whom he has had dealings with since 2001. "They make a lot of noise...they are desperately trying to copy ISET," noting that a "very low-cost CIGS process" using printable methods was developed at ISET during the late 1990s and that his company had a "specific goal of printable CIGS" since its earliest days. Other, now-expired patents from Kapur's collaborations cover plating, sputtering, and other methods for processing CIS/CIGS cells. The National Renewable Energy Lab (NREL) has been a staunch supporter of ISET through the years, Kapur told me. The company has survived on other government contracts, R&D projects, low-volume manufacturing of custom modules and systems, and a variety of service offerings. But after years of being "below the radar" and little of no venture capital support, ISET's main man told me "we will have product this year." The company hired chipmaking veteran Richard Kimmerle as its VP of manufacturing last March and is moving into a 300%+ larger space in Chatsworth, where the first production line will be built. Kapur mentioned that once he gets the final permits signed, then things will really get rolling at ISET's new plant, within about three months. He's also seeking a second round of financing, although he has sharp words for the VC community, whose business model he says is "broken.... We're not an overnight startup. The VC guys have no sense of how to work with folks who've worked long and hard on something. I didn't want to give up control." Yet certain potential investors "are talking very big, once the pilot line is perfected. Think about 100s of megawatts---money is not a problem." "We will have a pilot with 3 MW or 1 MW per shift," he explained. "Once the pilot is set up, the process characterized and streamlined, we will set up the team and then a 100 MW line. The line concept is a very simple, modular concept," with low capital costs, high material utilization, good material control, and high process yields. ISET will not employ roll-to-roll manufacturing yet, choosing batch methods for CIGS-on-glass for the time being, according to Kapur. "No company has an entirely roll-to-roll process for making solar cells." Of course, the challenge for ISET after doing it in the lab for 22+ years, is making the transition to commercial production. Kapur acknowledges the road won't be easy. "How do you make square miles of the stuff with proper composition and control?" Still, with his optimism and vision, he sees no reason that his nonvacuum ink-based process technology cannot result in "finished 10% conversion efficiency modules on the factory floor---for less than 65 cents per watt. The efficiency of CIGS will be scaled up to 15%, and then the price could drop below 50 cents per watt." He sees the vertical integration of glass factories with CIGS and even solar cells one day costing out to 40 cents per watt. Kapur sums up the challenges ahead, for ISET, Ascent, and the other CIGS start-ups. "The technology's there, now execution is the issue." The next few years will reveal which thin-film PV players have those execution skills and ramp to volume production, possibly following in the footsteps of CdTe TFPV pioneer First Solar---and which companies will become footnotes to the evolving story of solar power's march to grid parity and planetary ubiquity.