By Daniel Whitten

June 23 (Bloomberg) -- Harnessing and delivering enough wind power to make it a significant source of energy in the U.S. may raise its cost by 20 percent, according to the Pew Center for Climate Change.

Building transmission lines would cost as much as $4 billion a year, and managing its variability would add further to its price, the Pew Center said in a report today. Prices would still be competitive with other energy sources if the U.S. approves legislation to limit greenhouse gases, the group said.

With greenhouse-gas curbs in place, power from wind would be “more expensive than that from natural gas, but in many cases still less expensive than that from new nuclear or coal with carbon capture and storage,” Pew said in the report.

A climate and energy bill being considered by the U.S. House would mandate that 15 percent of power come from renewable sources such as wind, solar and biomass by 2025. The legislation also would require utilities that use coal and natural gas to buy permits for their emissions of carbon dioxide. President Barack Obama has set a goal for the nation to get 25 percent of its electricity from renewable sources by 2025.

“Acting now to regulate carbon through a cap-and-trade system and changing the way we plan and manage our electricity grid can help to make these cleaner energy sources a more significant part of the climate solution,” Eileen Claussen, president of the Arlington-based group, said in a statement.

Wind energy now costs between 9 and 12 cents per kilowatt hour, solar power costs between 24 cents and 59 cents, and natural gas ranges from 5 to 10 cents, the report says.

To contact the reporter on this story: Daniel Whitten in Washington at dwhitten2@bloomberg.net.

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