ERCOT More and more Meets Rising Demand with Photo voltaic, Wind, & Batteries

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Since 2021, electrical energy demand throughout the Texas electrical energy grid operated by the Electrical Reliability Council of Texas (ERCOT) has steadily elevated. Within the first 9 months of 2025, electrical energy demand in ERCOT, which manages about 90% of the state’s load, reached a document excessive in contrast with the identical interval in earlier years. Over those self same months, ERCOT had the quickest electrical energy demand development amongst U.S. electrical energy grids between 2024 and 2025. From January via September 2025, demand for electrical energy in ERCOT elevated 5% in contrast with the identical interval in 2024 to 372 terawatthours (TWh), 23% greater than the identical months in 2021. Since 2023, wind and photo voltaic era, particularly utility-scale photo voltaic, have been the fastest-growing sources of electrical energy in ERCOT and are more and more assembly rising demand.

Utility-scale photo voltaic generated 45 TWh of electrical energy within the first 9 months of 2025, 50% greater than the identical interval in 2024 and almost 4 instances greater than the identical interval in 2021, when utility-scale photo voltaic solely produced 11 TWh. Wind era via the primary 9 months of this yr totaled 87 TWh, up 4% in contrast with the identical interval in 2024 and 36% for the reason that identical interval in 2021. Collectively, wind and photo voltaic era met 36% of ERCOT’s electrical energy demand within the first 9 months of 2025.

Pure gas-fired era additionally elevated after 2021 however flattened extra not too long ago. Pure gas-fired era between January and September elevated to 161 TWh in 2023, 24% greater than the identical interval in 2021. Since 2023, pure gas-fired era remained comparatively flat, totaling 158 TWh between January and September 2025. Though it’s nonetheless the biggest supply of electrical energy for ERCOT, pure gas-fired era averaged 43% within the first 9 months of 2025, in contrast with 47% within the first 9 months of 2023 and 2024.

The forms of power sources used for electrical energy era can fluctuate on an hourly foundation, particularly throughout the summer season. Photo voltaic output is highest throughout noon hours, and the elevated availability of photo voltaic era in ERCOT in recent times has lowered the necessity for pure gas-fired era throughout that point of the day. Photo voltaic mills in ERCOT produced a median of 24 gigawatts (GW) between midday and 1:00 p.m. throughout the summer season months of June via September in contrast with a median of 12 GW of photo voltaic era at midday in the summertime months of 2023. Over the identical interval, the share of pure gas-fired era at noon fell from 50% in 2023 to 37% in 2025.

Batteries retailer electrical energy throughout daytime when era from wind and photo voltaic is the best, and so they provide electrical energy when era from wind and photo voltaic is declining. Starting in October 2024, ERCOT started reporting battery output individually in its hourly grid information. In the summertime months of 2025, batteries helped provide electrical energy within the night as photo voltaic output declined, supplying a median of 4 GW within the 8:00 p.m. hour.

ERCOT’s electrical energy demand is forecast to develop sooner than that of some other grid operator in the US via a minimum of 2026. In our October Brief-Time period Power Outlook, we forecast demand will rise one other 14% within the first 9 months of 2026 in contrast with the identical interval this yr, reaching 425 TWh.

Principal contributors: Kimberly Peterson, Tyler Hodge