by Debra Vogler, senior technical editor, Photovoltaics World
June 17, 2009 – Oerlikon Solar announced during Intersolar Munich that it had achieved 11% initial power conversion efficiency on its full-size micromorph (a thin film technology) modules (1.4m2), or 151Watts of initial power. That news, along with unbridled optimism about the future of crystalline silicon (c-Si) exhibited at the recent Intertech-Pira Photovoltaics Summit, provided the backdrop for an interview with Oerlikon’s Chris O’Brien, head of market development, North America.
The company says its micromorph technology boosts solar-cell efficiency by adding a second microcrystalline absorber to the amorphous silicon (a-Si) layer, which converts the energy of the red and near-infrared spectrum, facilitating efficiency increases of up to 50%. The company ran a batch of five full-sized modules through its pilot line in Switzerland, using the same manufacturing process and materials already in use by the company’s end-users. The initial 11% efficiency will probably stabilize to ~9.7% on those five modules, O’Brien told PV World, but “what was encouraging about the results is that the absolute number was a significant boost over what we’re guaranteeing today [and] the spread among the modules was quite tight [3W] — so that gives us confidence that this is a replicable result.”
Micromorph thin-film cell cross-section. (Source: Oerlikon Solar)
Based on data from 10 identified end-users, Oerlikon is on track to meet its roadmap goal whereby end-users will be able to produce panels at a cost of $0.70/W by the end of 2010, O’Brien said — a cost that the company believes will put end-users in a competitive position with respect to the broader renewables market, and would allow delivery of solar-generated electricity at a price of ~$0.09/kW-hr for one large scale project currently being developed in California, “a very competitive price in the large wholesale markets,” O’Brien noted. To meet its roadmap goal, the company is continuing to improve efficiency in its micromorph technology, and improve its manufacturing process (e.g., throughput, yield, etc.). By the end of 2009, after two years selling its end-to-end solution, it will have 600MW cumulative capacity installed at different sites in Europe and Asia, O’Brien noted.
O’Brien also addressed the points frequently being discussed at technical conferences (like Intertech-Pira) — i.e., grid parity — and the seeming concurrence among industry insiders of a constant 80%/20% split (or maybe 70%/30%) of market share that favors c-Si over thin-film PV. “There’s so much interest in thin-film technologies in general because they have dramatically simpler manufacturing steps and use much less material when making a module compared with c-Si,” explained O’Brien. For its part, Oerlikon expects thin-film “will grow to at least 25% of market share by 2012,” he said. “There will continue to be a strong market for c-Si, but the fastest growth will be in thin-film technologies because of inherent cost advantages.”
O’Brien also believes that current market conditions for c-Si are somewhat distorted — he told PV World that he has heard estimates of anywhere from 1-2GW, or 20%-40%, of last year’s market volume in c-Si is in excess inventory. “There is a lot of product looking for a home and c-Si modules are being offered in large volume for very low prices,” he said, and he doesn’t expect this situation to persist in the long term. Oerlikon believes there is a potential market that becomes addressable once its goal (i.e., modules at $0.70/Watt) is met, he said, and end-users will have an even greater potential to sell not just into today’s incentive-driven markets, but into much larger emerging markets for solar energy that is competitively priced with other conventional or renewable energy options.
Regarding grid parity, though, O’Brien thinks it’s a simplistic notion. “Delivering energy value is one part of the equation, but there are many other factors,” he noted. “In the case of large projects in the West, there are issues such as having access to electricity transmission, policies that help project developers interconnect to the grid in a relatively simple way, etc. There are numerous other steps that are part of the process to effective grid integration — but a pre-requisite to that happening is reaching a value point where solar is competitive effectively against the other peak energy alternatives.” Responding to recent observations that in Hawaii the price of solar-generated electricity has already gone below grid parity and has not yet “taken off,” O’Brien believes it has more to do with these other factors.
In summary, O’Brien believes that the overall PV markets will increase and thin-film will need to deliver on its technology roadmap, and he disputes the market share pessimism. “When thin-film gets to $0.70/W, it will get a larger share of the market,” he said, suggesting that there is a very large market for any solar tech that can deliver electricity in the $0.10-0.12/kW-hr range. “We have a clear path to this point,” he added, whereas “it’s not as clear to me that c-Si has a clear pathway to that same operating point on a sustainable basis.” The thin-film path, then, depends on significant improvements in the technology’s cost structure and a return to equilibrium in c-Si module prices. — D.V.
This article was originally published by Photovoltaics World.