TVA urges power conservation due heat wave

NEW YORK Aug 10 (Reuters) - With temperatures soaring around the 100-degree F (37.8 C) mark this week across the U.S. Southeast, the Tennessee Valley Authority and local power companies on Monday urged customers to conserve electricity to help maintain grid reliability and save money.

"TVA has sufficient resources available to meet the current need. But every consumer can play a role in reducing electricity demand and costs by conserving energy where they work and live," Robert Balzar, TVA vice president of Energy Efficiency and Demand Response, said in a release Monday.

TVA expected demand to remain high until the weekend. Temperatures in Memphis, Tennessee, the biggest population center in the TVA territory, were expected to reach the triple digits every day through Saturday, according to forecasters.

Balzar said summer energy use normally is highest between 2 and 8 p.m., when TVA and other power suppliers are most likely to need to operate higher-cost peaking generators and purchase more expensive electricity from outside sources to help supply keep up with demand.

TVA said monthly average temperatures in May, June and July were all above normal. The average temperature in July was 93 degrees, three degrees above normal. August is expected to be four degrees above normal.

The above normal temperatures have kept at least one of TVA's power plant's, the 3,274-megawatt Browns Ferry nuclear plant in Alabama, operating at reduced power or shut for several days since mid July due to high water temperatures in the Tennessee River, which the plant uses for cooling.

"Our system is seeing the highest demand for electricity so far this summer and the highest peak energy use since 2007," Balzar said.

Last week, TVA customers used more than 31,700 MW on Aug. 4. The system's all-time record is 33,482 megawatts set on Aug. 16, 2007.

TVA, which is owned by the U.S. government, operates 29 hydroelectric dams, 11 coal-fired power plants, three nuclear plants and 11 natural gas-fired power facilities with a capacity of 33,700 MW. It provides power to utility and business customers serving about 9 million people in most of Tennessee and parts of Alabama, Mississippi, Kentucky, Georgia, North Carolina and Virginia.

THE SOUTH IS BAKING

TVA was not the only power company to experience high demand on Aug. 4.

The Electric Reliability Council of Texas (ERCOT), the grid operator for most of the state, set a new demand record on Aug. 4 of 63,594 MW, exceeding the previous record of 63,400 MW on July 13, 2009. See [ID:nN04276359]

ERCOT said the region has adequate generation to cover an expected summer peak over 64,000 MW and still maintain a 21 percent cushion of reserves to cover unexpected major outages.

One megawatt is roughly enough electricity for 500 average homes under normal conditions in Texas, or about 200 homes during hot weather when air conditioners are running for longer periods of time.

Extreme temperatures and high humidity across Arkansas, Louisiana and Texas also sent electric usage in American Electric Power Co Inc's (AEP.N) Southwestern Electric Power Co (SWEPCO) to a new all-time high level.

SWEPCO customers used a record peak of 4,990 MW on Aug. 4, breaking the old mark of 4,950 MW set August 4, 2008. (Reporting by Scott DiSavino)