Texans could experience calls to reduce electricity usage — or even power outages — this winter if the grid experiences very high demand for power, estimates from the Electric Reliability Council of Texas show.

Ahead of each season, ERCOT, which operates the state power grid, estimates how much power supply will be available to meet projected needs — serving as an early indicator of risk. The winter report published Tuesday shows that very high demand during winter weather could force ERCOT to ask Texans to cut back on electricity usage to avoid an emergency.

And in the most extreme scenario considered for this winter — a combination of high electricity usage, power plant outages and very low wind and solar energy production — the grid would need to resort to rolling blackouts, the report shows.

“It is critically important to address the fact that … under the most extreme conditions, there could be not enough power,” said Pablo Vegas, president and CEO of ERCOT. “That’s not acceptable.”