New Efficiency Record for A-Si Panels

The National Renewable Energy Laboratory has confirmed results for a record-breaking conversion efficiency in solar cell technology. Oerlikon Solar and Corning Incorporated have combined technologies to produce a tandem solar cell using thin-film silicon. Oerlikon’s proprietary Micromorph® solar cells and Corning’s specialty, advanced light-capturing glass combined to achieve 11.9-percent stabilized conversion efficiency in NREL tests.

That efficiency beats out the previous record of 11.7 percent in 2004. This is the latest advancement in Oerlikon’s ThinFab line of solar panels, which, according to the company, have also achieved a world record in production cost per watt at 50 euro cents per watt-peak (about $0.64 USD).

Micromorph technology is itself an advancement on amorphous silicon solar cells (a-Si cells). Put simply, a-Si cells consist of a thin layer of silicon deposited onto a transparent conductive oxide (TCO). Oerlikon’s Micromorph technology adds another layer in tandem with the first. This added microcrystalline absorber enables the solar cell to absorb a wider spectrum of light, edging into the red and near-infrared spectrum which conventional silicon solar cells cannot do. According to Germany-based Oerlikon this extra absorption increases cell conversion efficiency (the rate at which sunlight is converted into electricity), by 30 percent.

Corning Inc.’s proprietary glass, or glazing, technology ensures that a higher amount of light is available for absorption by the solar cells beneath it. It is in this way that the two companies continue to make advancements in thin-film silicon.

Low production costs have long been a point of pride for thin-film technologies. Last year, American firm First Solar broke the coveted $1.00/watt barrier (now residing at about $0.76/watt) for its cadmium telluride solar cells (CdTe). Yet low conversion efficiency has been the only factor preventing thin-film products from surpassing their crystalline silicon predecessors, which still dominate more than 90 percent of the global solar market.

However, with efficiencies nearing 12 percent and production costs approaching a half dollar, the gap continues to close between first- and second-generation technologies. Most crystalline silicon (c-Si) modules on the market produce at efficiencies between 15 and 20 percent, but cost well over $1.00 per watt to manufacture. a-Si products use much less silicon and are cheaper to produce than conventional panels. It’s for this reason — and based on advancements such as Oerlikon and Corning’s — that thin-film solar cells are expected to take over dominance of the solar market within the next decade, depending on a variety of technological and commercial factors.

Oerlikon Solar is presenting its record-breaking Micromorph technology this week at the 25th Annual European Photovoltaics Solar Energy Conference in Valencia, Spain.

Suntech Power Stops Producing Thin Film Panels

Suntech Power Holdings Co. Ltd. plans to overhaul operations at its Shanghai, China, manufacturing facility to focus on the manufacture of crystalline silicon solar cells. As part of the restructuring, the company has ceased the manufacture of amorphous silicon thin-film solar panels.

Suntech expects to incur a thin-film equipment non-cash impairment charge of approximately $50 million to $55 million in the second quarter of this year. The company cites "rapid cost reduction and improving competitiveness of crystalline silicon solar panels" as the reasons for its decision to switch manufacturing focus at the Shanghai factory.

SOURCE: Suntech Power Holdings Co. Ltd.

1.2 GW Solar Panel Factory to be built in Siberia

A Russian company is hiring several German firms to build a 1.2-gigawatt solar factory complex in southwestern Siberia.

Silarus, a subsidiary of the chemical company Titan, has hired the Schmid Group, Schmid Silicon Technology and EPC Engineering Consulting to build the factory, reported Photovoltaics World. Silarus signed the agreements with the German companies at a raw materials conference in Moscow last month.

The complex reportedly would have a plant capable of producing 10,000 metric tons of polysilicon per year. It would also have production lines for wafer, cells and panels. The overall project would cost about €1.6 billion ($2.4 billion).

The project is likely to be built in phases. Few companies in the world have the gigawatt capacity. First Solar in the United States and Suntech Power in China are among them.

Russia hasn't been a hot bed for solar manufacturing, but it seems to have that ambition. It's home to Nitol Solar, a polysilicon producer.

Earlier this year, a Russian investment firm, Renova Group, said it was teaming up with the Russian Corporation of Nanotechnologies to build a 120-megawatt factory to make solar panels in central Russia (Chuvashia).

The joint venture, called Nano Solar Technology (NST), has ordered equipment from Oerlikon Solar in Switzerland, and plans to start installing it in 2010. The equipment would enable NST to produce solar panels that rely on amorphous silicon and microcrystalline silicon to convert sunlight into electricity.