The three GE patents, issued in 1992, 2005 and 2008, are related to variable-speed turbines that adjust to ensure that a consistent amount of power is supplied to the grid without damaging the machines, and that deal with periods when voltage on the grid is low, such as during an outage.
The commission said it would issue an opinion detailing its reasoning. ”GE believes strongly in the merits of its case against MHI, and we will continue to protect our technology in the U.S. and around the world,” company spokesman Dan Nelson said in a statement.
Tom Aiyama, a spokesman for Mitsubishi, told that it was pleased with the decision but wanted to analyze it before deciding on future strategies.
The case comes as larger wind turbines are becoming more popular, particularly in the West, because they take up less land and can be more cost effective to operate, Emerging Energy Research analyst Matt Kaplan said.
GE, based in Fairfield, Conn., and Mitsubishi have pegged 2010 as key for large turbines, Kaplan said in a telephone interview this week. Mitsubishi has a 2.4 megawatt product and GE has a 2.5 megawatt product.
Manufacturers that use GE’s technology have purchased licenses from GE or developed technology to circumvent the patents.
Mitsubishi manufactures components for the wind turbines in Japan and Mexico and imports them to the United States where the machines are built. The company is planning to build a $100 million turbine manufacturing facility in 2011 in western Arkansas in 2011.