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The photovoltaic (PV) industry has historically relied on high purity silicon produced in the silicon submerged arc furnace (referred to as metallurgical silicon) and refined in the Siemens process. Demand for that silicon, the most critical and costly material in solar cell panels, exceeded supply beginning in 2005, running spot prices as high as $400 per kg. A decade earlier, silicon sold for as little as $25 per kg, as excess capacity existed for producing purified silicon. Today growth of the PV industry is limited by availability and cost of silicon. The dramatic increase in the cost of silicon in 2005 forced some PV producers into bankruptcy, others closed production lines, and major energy companies without secure suppliers for silicon divested themselves of their solar subsidiaries.

Professors David Lynch at the University of Arizona, and Harald Øye at the Norwegian University of Science and Technology developed a new method for refining silicon using a metallurgical process that relies on inherent chemical reactivity of impurities in metallurgical silicon. With the new method, processing now removes impure elements to acceptable levels for solar cells; a seemingly small but significant breakthrough in decreasing the cost and environmental impact of silicon production.

Silicon-based photovoltaics amount to over 90% of the current market. While that percentage is expected to shrink over the next decade, the rapid growth in demand for photovoltaics, and the longevity of silicon solar cells, makes production of silicon -based photovoltaics a growth industry for the future. That future is now brighter that the new refining process can reduce production costs of purified silicon up to 50%. Prior to the shortage of silicon for the PV industry, silicon constituted 40% of the cost of a silicon photovoltaic cell and 25% of the final panel cost, the new refining process will make a major contribution in reducing the cost of solar energy to the end user.

Professional Organizations:

1. TMS
2. CIM
3. ACerS

Selected Publications

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1. David C. Lynch and Harald A. Øye, Silicon Refining Process, United States Patent Application, US 2007/0245854 A1, 25 pp., Oct. 25, 2007.
2. D.C. Lynch, and M.A. Lynch, “The Search for a Low Cost Solar-Grade Silicon, in Silicon for the Chemical Industry VII (Symposium Sept. 21-24, 2004), H.A. Øye, A. Holas, and L. Nygaard, eds., Taper, Trondheim, Norway, pp. 307-318, 2004.
3. D.C. Lynch, “Physical Chemistry of Silicon Production: Phosphorus in the Arc Furnace and Catalytic Elements in the Rochow Process,” in Silicon for the Chemical Industry VII (Symposium Sept. 21-24, 2004), H.A. Øye, A. Holas, and L. Nygaard, eds., Taper, Trondheim, Norway, pp. 17 -31, 2004.
4. Lynch, D.C., “Thermodynamics for the Silicon Industry: A Look at Advancements in the Last Decade,” in Silicon for the Chemical Industry VI, H.A. Øye, H. Rong, L. Nygaard, G. Schüssler, & J. Kr. Tusel eds., Taper,Trondheim, Norway, June 2002, pp. 73-91.