Market Information System Grid and Market Conditions

News Release

February 02, 2011

Conservation Needed; Possibility of Rotating Outages


ERCOT is asking consumers to reduce energy consumption during peak-demand times this evening -- 6-10 pm – and tomorrow morning from 6 – 8 am.

The grid continues to have more than 5,000 MW of generation out of service due to the effect of the extreme cold.

Tonight’s peak demand is forecast to hit 54,900 MW between 7-8 pm. The morning peak was 53,223 MW – with 4,000 MW dropped via rotating outages -- at 9-10 am.

At this time, the forecast for tomorrow’s peak load is 56,800 MW for 7-8 am.

ERCOT’s current record for all time winter peak demand is 55,878 MW, which occurred on Jan. 8, 2010.

Rotating outages are controlled, temporary interruptions of electrical service initiated by each utility when supplies of reserve power are exhausted. Without this safety valve, generators would overload and begin shutting down to avoid damage, risking a domino effect of a state-wide outage.

Utilities/ transmission providers determine the location/scheduling of the rotating outages.

Previous news releases below and on website: (To receive news releases by email, go to the Email List Manager ( and select "News_Bulletins.")

The Electric Reliability Council of Texas (ERCOT) manages the flow of electric power to more than 26 million Texas customers -- representing about 90 percent of the state’s electric load. As the independent system operator for the region, ERCOT schedules power on an electric grid that connects more than 46,500 miles of transmission lines and 710+ generation units. It also performs financial settlement for the competitive wholesale bulk-power market and administers retail switching for nearly 8 million premises in competitive choice areas.

ERCOT is a membership-based 501(c)(4) nonprofit corporation, governed by a board of directors and subject to oversight by the Public Utility Commission of Texas and the Texas Legislature. Its members include consumers, cooperatives, generators, power marketers, retail electric providers, investor-owned electric utilities, transmission and distribution providers and municipally owned electric utilities.