Tax measure takes wind out of U.S. sails Three of six wind turbines of the Somerset Wind Farm are shown on a mountain ridge on June 19, 2012 near Somerset, Pennsylvania. Wind power has expanded in the United States over the past decade and is now about 3 percent of all electric power in the country. WASHINGTON, July 9 (UPI) -- Development of the largest wind farm planned in the United States hinges on congressional approval of a federal tax credit, a company spokesman said. U.S. President Barack Obama has pressed for a comprehensive energy initiative that calls for more oil and natural gas production in coordination with a push for a greener economy. The wind energy sector, however, could suffer as a federal tax credit is set to expire. Greg Wetstone, a spokesman for wind energy company Terra-Gen Power, told the Platts news service that the expansion of a 1,020-megawatt wind farm in California is "very much contingent on Congress passing the production tax credit extension." Lawmakers are likely to hold off on the measure until after U.S. presidential elections in November. Phyllis Cuttino, director of the Pew Clean Energy Program, writes in the Huffington Post that the tax credit has lead to a twelve-fold increase in domestic manufacturing of wind turbine components since 2006. Without a tax credit, she writes, investors may be hesitant to back renewable energy programs. "Wind installations have declined by 73 to 93 percent in years without a production tax credit," she writes.