The Biden administration declared a power emergency in Texas amid soaring electricity demand sparked by a brutal heatwave.

The order issued by the Energy Department on Thursday allows the state’s grid operator to waive some air- pollution limits so generators can produce more power. It is in affect until 9 pm local time Friday.

The Electric Reliability Council of Texas, which oversees the grid serving 90% of Lone Star State customers, requested the emergency order “to preserve the reliability of the bulk electric power system.”

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“The emergency nature of the expected load stress caused by the current extreme heat event threatens to cause loss of power to homes and local businesses in the areas that may be affected by curtailments, presenting a risk to public health and safety,” the Energy Department said in its order.