Texas’s fragile power grid will be pushed to the brink in coming days as unusually hot weather grips the second-largest US state.

Electricity usage is forecast to break the all-time high by the end of the week, the Electric Reliability Council of Texas, or Ercot, warned. With temperatures expected to top 100F (38C) in Houston, Dallas and other Lone Star State cities, air-conditioning use is expected to soar to 80.3 gigawatts on Thursday and even higher on Friday. The record set last summer was 80.1 gigawatts.

Power supplies will be especially stretched on Friday when demand is projected to hover at a record level for four consecutive hours, according to Ercot data. The reserve margin — or buffer of extra electricity supplies — may shrink to as little as 5.3% during that stretch.

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The Texas grid normally doesn’t see demand spike this early in the cooling season. With temperatures already in the high 90s in Houston and elsewhere, Ercot has yet to issue any formal appeals for consumers to conserve power.

Author: Naureen S. Malik