(Reuters) - The Texas electric grid urged consumers to cut back on power usage this week to avoid straining the electric system with homes and businesses expected to crank up their air conditioners to escape a heat wave.
Temperatures hit about 100 degrees Fahrenheit (38 Celsius) in Houston, San Antonio and Dallas, the three biggest cities in the Lone Star State, on Sunday and were expected to reach the triple digits for several more days this week, AccuWeather.com forecast.
The Electric Reliability Council of Texas (ERCOT), the grid operator for most of Texas, said in a release it was looking closely at anticipated electric use and available electric generation.
Peak electric demand was expected to exceed 65,000 megawatts (MW) on Monday and Tuesday, and ERCOT said it expects to have adequate electric generation resources available to serve that load without activating emergency programs that could lead to curtailment of power to certain industrial customers or broader rolling outages.
The grid operator said its plan for the week takes into account current outages and the possibility of losing additional resources.
One megawatt is enough to serve about 200 homes during peak demand, and ERCOT's record peak was 68,379 MW in August, 2011.
ERCOT has warned that rolling outages could occur this summer given the state's limited amount of surplus generation.
An extended heat wave and drought last summer forced ERCOT to declare emergencies on six days and curtail power to interruptible customers on two days in August to avoid widespread rolling outages.
The state's shrinking reserve margin has led regulators to implement a number of wholesale market changes to encourage construction of new power plants.
Several idled power plants have been returned to service to bolster the summer supply this year after a new coal-fired plant expected to be operational was delayed.
In May, Texas set a monthly power demand record of 59,037 megawatts, surpassing the previous high set in May 2011 by 2.9 percent, according to initial ERCOT data.
In 2011, power use in ERCOT rose 5 percent from 2010 as the state experienced extremely cold weather in February, which forced ERCOT to implement rolling outages, and the hottest summer on record.
The biggest transmission and generation companies in Texas include units of privately-held Energy Future Holdings, CenterPoint Energy, American Electric Power, Entergy, Xcel Energy, El Paso Electric, PNM Resources, NRG Energy, Exelon, NextEra Energy and Calpine.
(Reporting by Scott DiSavino in New York and Eileen O'Grady in Houston;editing by Sofina Mirza-Reid)