The Tennessee Valley Authority could shut down more than one-third of its coal-fired power plants and add more nuclear, gas and renewable generation to make up for any shortfall in power generation, according to a blueprint released Thursday.
In a draft of its integrated resource plan, which covers the next 20 years, TVA planners also said the utility could cut the growth in its peak power demand by up to 6,000 megawatts - or more than 15 percent - by time-of-day pricing, energy audits and incentives for power conservation.
The preferred choices emerging from TVA's most comprehensive plan in 15 years suggest that the nation's biggest government utility should limit the use of coal, which now fuels more than 60 percent of TVA's power generation.
In its place, TVA could nearly triple its use of natural gas and add the equivalent of four more reactors to the six nuclear units it now operates and one it is finishing at the Watts Bar Nuclear Plant near Spring City, Tenn.
TVA also is considering programs to significantly boost generation from wind, solar and biomass while promoting more energy conservation.
The recommendations stem from a yearlong study of future alternatives for TVA, which supplies electricity to more than 9 million consumers in seven Southeastern states.
TVA Senior Vice President Van Wardlaw said the study updates TVA's last integrated resource plan, completed in 1995, and will guide TVA "toward a cleaner and more secure energy future, relying more on nuclear power and energy efficiency and less on coal."
Find out more
TVA will conduct public hearings on the proposed Integrated Resource Plan
* Oct. 5 in Bowling Green, Ky.
* Oct. 7 in Olive Branch, Miss.
* Oct. 13 in Knoxville
* Oct. 14 in Huntsville, Ala.
TVA President Tom Kilgore outlined a similar vision to the TVA board in August, pledging to make TVA the nation's leader in developing more nuclear power and the utility leader in the Southeast in promoting energy efficiency.
The draft plan outlined Thursday will be discussed at public hearings in October. The TVA board is scheduled to identify its preferred alternative from the blueprint by next spring.
Gary Brinkworth, a senior manager for TVA who helped work on the integrated resource plan for the past year, said the three most favorable alternatives included in the study will be tested in coming months. The plan is designed to be flexible enough to accommodate economic, regulatory and consumer choices, he said.
Regulatory restrictions proposed for carbon, smog and mercury emissions, if fully adopted, could lead TVA to idle 4,700 megawatts of coal-fired capacity as soon as 2015, Brinkworth said.
"With such regulations, it's just not cost effective to install the required maximum available control technologies on many of our older units," he said.
TVA recently announced plans to shut down 1,000 megawatts of coal generation by closing units at its Widows Creek, John Sevier and Shawnee Fossil Plants within the next five years.
The new plan outlines some alternatives that would also idle, or "lay-up," most of TVA's oldest coal units, including those at Johnsonville in West Tennessee, Colbert in North Alabama and other units at John Sevier in upper East Tennessee.
Environmental groups who support more air pollution limits on coal plants welcomed TVA's plans, although they urged TVA to do even more to promote conservation and efficiency.
"Unfortunately, using the term 'lay-up' leaves the option open for these (coal) plants to be brought back on-line in the future," said Stephen A. Smith, executive director of the Southern Alliance for Clean Energy and a member of the panel that helped review the plan recommendations. "These dirty, inefficient power plants need to be shut down once and for all as we transition to cleaner sources of energy."
Smith said TVA should do even more to promote conservation to limit the need for what he said were "high-risk" nuclear power plants for more generation. Tennessee has the highest per capita residential use of electricity in the country and five neighboring states are among the top eight in electricity consumption, according to the U.S. Energy Information Administration.
New energy sources
TVA planners don't plan to build any new conventional coal plants, but one alternative is to build a plant with integrated gasification combined cycle, or IGCC, which uses synthetic gas from coal for up to 500 megawatts of power.
TVA's preferred alternatives in the plan suggest the agency could boost its total natural gas-fired capacity from 7,500 megawatts up to 20,700 megawatts of gas-fired capacity by 2030.
The plan also suggested TVA could add renewable energy from wind, solar and biomass up to 1,200 megawatts - an amount equal to one of TVA's nuclear reactors.
Brinkworth said TVA also has begun looking for sites for a possible pumped storage plant similar to the Raccoon Mountain Pumped Storage Facility just west of Chattanooga. Such a facility, which stores water atop a mountain in a manmade lake on, acts like a giant battery to help TVA produce power when it is most in demand.
Contact Dave Flessner at email@example.com or 423-757-6340. Follow him on Twitter at twitter.com/chattreporter.