The TVA board authorized the utility's staff to negotiate with outside suppliers for the renewable energy. Earlier this year, TVA received more than 60 proposals for renewable power generation, most of which involved wind generation from the Midwest, TVA Vice President Van Wardlaw said.
The federal utility is looking to buy more renewable power to help prepare for an expected federal mandate that electric utilities generate a bigger share of their power from renewable sources.
Congress is debating several measures that would require 20 percent of a utility's power to come from either wind, solar, biomass or new hydro generation.
"I consider this is to be a very important step forward for TVA," said Howard Thrailkill, chairman of the TVA board's operations committee. "This gives me particular pride that we have gone this far."
But TVA officials said most of the proposals for the renewable energy came from wind generators outside of the Tennessee Valley.
"These are different sources than we have used in the past and there will be some challenges" getting delivery of the power from distant sites, Mr. Wardlaw said.
Even with the renewable purchases authorized today, TVA will have to secure other sources of renewable power if Congress sets a 20 percent renewable portfolio standard for 2020.
When the wind is blowing and the sun is out, the 2,000 megawatts TVA could purchase under today's action would be equal to nearly the entire output of the twin-reactor Sequoyah Power nuclear plant. But TVA officials stressed that wind and solar power don't operate all the time, so the actual net output from the renewable sources over the course of a year would be only about one-third as much as the Sequoyah plant.
"We expect the market to change rapidly in the next few years," Mr. Thrailkill said. "But it's important for us to get started."