Gintech Energy Corp, a Taiwan-based solar cell manufacturer, will start shipping the "Douro," a polycrystalline silicon solar cell with a conversion efficiency of 16.6%, in March 2009.
It is the world's highest efficiency for polycrystalline silicon solar cells manufactured with existing structures, materials and processes, according to the company. However, the current conversion efficiency of the cell is "16.4% or more" on average.
"We will realize an average conversion efficiency of 16.6% or more by the time we start shipping the product," said Harry H.H. Kuo, product manager and technical manager of Gintech.
The company will aim for an average conversion efficiency of 17.5% for the future.
Almost same pricing
Gintech has not introduced any special process to raise the conversion efficiency of the cell to be shipped in March. Using the same manufacturing process as before, the company could maintain the high yield. As a result, it can ship the new solar cell at almost the same price as that of its previous product with a one-point lower conversion efficiency.
Gintech will switch all of its solar cells to the new type in one year from the first shipment in March. In addition, it plans to boost the current yield of 97% to 97.7% or higher.
The new cell measures 156 x 156mm, and the substrate is 180 to 200μm thick. The conversion efficiency was measured at Fraunhofer ISE (Instituts fur Solare Energiesysteme). Gintech is currently selling its cells in 42 categories with conversion efficiencies from 15 to 17%.
Monocrystalline Si cells, color cells
In addition to the polycrystalline silicon cell, Gintech enhanced the conversion efficiency of its monocrystalline silicon solar cell to 17.1% or higher on average by improving the manufacturing process.
Furthermore, the company developed color cells that look green, purple, gray or silver by adjusting the surface layers of cells. Their conversion efficiency is equal to that of the company's standard cells, about 16% at maximum. These cells are targeted at BIPV (building integrated photovoltaics) applications.