Economic growth and population increases, in addition to the triple-digit heat, contributed to the strain on the state’s largest bulk transmission grid for electricity this summer, according to the grid’s top official.

H.B. Doggett, president and CEO of the Electric Reliability Council of Texas, said conditions of the last two weeks have “posed a particularly serious challenge to the electric grid.”

After two days of declines in peak demand, Texans on Friday increased their demand for electricity to 65,282 megawatts — up from Thursday’s 63,434.

The top eight days of electricity demand ever experienced by ERCOT, which serves three-fourths of the state, occurred this month, including an all-time high of 68,295 on Aug. 3. There were also four days of energy-emergency alerts last week, but planned residential outages were avoided.

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