Last Updated on May 22, 2022 by Mary Pressler
ERCOT Capacity Assessment for Summer 2022
The Grid Has 22.8% Reserve Margin
On Monday May 16, ERCOT published the Seasonal Assessment for Resource Adequacy covering the months of June-September 2022. The grid operator is expecting a record breaking demand of 77,317 megawatts (MW), but the capacity available will be 91,293 MW. This summer, Texas will most likely exceed the 74,820 MW demand peak from August 2019.
- ERCOT has a reserve margin of 22.8% for summer 2022, which is well above the 13.75% target.
- According to ERCOT CEO Brad Jones, Texas only had a reserve margin of around 16% in 2021, when Winter Storm Uri caused widespread blackouts.
The ERCOT assessment includes 473 MW of natural gas, solar and wind generation that will be added to the grid by summer. The grid will also have access to 2,035 MW of battery storage, which is characterized by its fast response to changes to power demand and supply. However, ERCOT is not counting energy storage in the reserve margin calculation, since it doesn’t provide sustained capacity. Grid batteries are better suited for short-term events that require a quick response to keep voltage and frequency stable.
Hot Weather and Power Plant Failures Tested the Grid on May 13
On Friday, May 13, the ERCOT grid was tested by a combination of high temperatures and the sudden failure of six power plants. The total generation capacity taken offline was 2,900 MW, which is enough to provide electricity for 580,000 homes. One of the power plants that failed was about to receive scheduled maintenance, but ERCOT instructed the owner to delay repairs and keep the plant available during the incoming heat wave.
The power plant failures happened just before a weekend where Texas was expecting temperatures of around 100°F. This raised concerns that the high air conditioning load could cause blackouts. ERCOT instructed electricity consumers to conserve energy in response, and the following measures were implemented from 3 pm to 8 pm, from Friday to Sunday:
- Raising thermostats to at least 78°F.
- Avoiding the use of large appliances during the specified hours.
Fortunately, no major disruptions of the power supply were reported during the weekend, and the affected power plants were resuming normal operations by Saturday. Power plant maintenance is normally scheduled for spring and fall, where the grid tends to have a lower and more predictable demand. However, the opportunity window for maintenance has been shortened by the above-average temperatures affecting Texas in May 2022.
Recommendations for TX Homes and Businesses
ERCOT announced a high reserve margin for summer, but energy conservation is still recommended for homes and businesses regardless. Keep in mind that electricity prices are determined by supply and demand in Texas. Unless you have a fixed-price contract, you can expect high prices when the hottest weeks of summer arrive.
According to the US Department of Energy, you can save up to 10% on annual heating and cooling costs, simply by setting back the thermostat 7-10°F for 8 hours per day. Even when ERCOT doesn’t announce energy conservation measures, moderate thermostat settings can save you hundreds of dollars in the long run.