in global production of PV followed by China, with Japan in third place.22 But the growth of international production means that three of the top five manufacturers of PV modules (measured in megawatts of shipments23) in 2010 were Chinese. The firm in second place on the basis of its volume (megawatts) of shipments at the end of the fourth quarter of 2010 is First Solar, a U.S. thin-film PV company that uses cadmium telluride instead of silicon (the material used by all 9 other companies in the top 10) as its semiconductor. First Solar has manufacturing facilities in Perrysburg, Ohio; Frankfurt, Germany; and Kulim, Malaysia. There are no other U.S. companies in the top 10. The Japanese company Sharp is in fourth place, and a Canadian company, Canadian Solar, is in sixth place. The top 10 manufacturers accounted for more than 50 percent of total global PV shipments in 2010.24
Although the United States no longer dominates global production of solar modules, it has maintained its lead in patenting in solar technologies,25 followed by Japan (according to the geographic location reported by the corporate assignees on the patent). As can be seen in Figure 7.2, the United States was the dominant source of solar technology patents during 1975-1995, although Japan’s share of global patenting increased significantly after 1980.26 The United States retains a position of leadership in solar-related USPTO patents, accounting for 52 percent of total solar patents in 2002-2010, followed by Japan at 26 percent and Germany at 6 percent.27 The 10 leading corporate patentees during 2002-2010 were (in order) Canon (Japanese), Sharp (Japanese), Boeing (U.S.), Sunpower (U.S.), Kanegafuchi (Japanese), Sanyo (Japanese), Emcore (U.S.), Applied Materials (U.S.), Konarka (U.S.), and Rabinowitz (U.S.).28
As this discussion suggests, the United States no longer is among the leading
22 Le, Minh, Chief Engineer, Solar Energy Technologies Program, U.S. Department of Energy. 2011. “The SunShot Program—The Great Solar Race: The Apollo Mission of Our Times.” Presentation to the NRC Committee on Harnessing Light: Capitalizing on Optical Science Trends and Challenges for Future Research, February 24, 2011.
23 The conditions for measuring the nominal power of a photovoltaic module are specified in standards such as IEC 61215, IEC 61646, and UL 1703; the term “power” is also used in describing the size of a shipment or an installation.
25 The above-described data are based on shares of patents in the U.S. Patent and Trademark Office database. Past research suggests that U.S. patents are a reasonable measure of unique inventive activity worldwide by internationally competitive companies. Here, patent locations are assigned on the basis of company assignee location, as reported in the filed patent.
26 Andersson, B.A. and S. Jacobsson. 2000. Monitoring and assessing technology choice: The case of solar cells. Energy Policy 28(14):1037-1049.
27 Cardona, V. 2011. “Clean Energy Patents—Winners and Losers, Renewable Energy World.” Available at http://www.renewableenergyworld.com/rea/news/print/article/2011/03/2010-clean-energy-patents-winners-and-losers. Accessed July 5, 2011.
28 Cardona, V. 2011. “Clean Energy Patents—Winners and Losers, Renewable Energy World.”