Title: Electric Grids in Texas and Central U.S. May Face Power Shortages Amid Heatwave
Date: August 24, 2023
Two electric grids in the United States are at risk of not having enough power to meet demand and required reserves due to an ongoing heatwave in Texas and other Central states. The Electric Reliability Council of Texas (ERCOT), which manages the grid for over 26 million customers, has called for voluntary power conservation as it anticipates a potential shortage.
ERCOT has expressed concerns about a reserve capacity shortage, stating that there is currently no market solution available to address the situation. Power grids typically maintain reserves to ensure the system’s reliability in case of unforeseen events such as power plant or transmission line failures.
When a grid’s resources are insufficient to fulfill demand and maintain required reserves, operators may implement emergency measures to reduce usage and increase supplies. These measures can include importing power from neighboring regions, urging energy conservation, or resorting to controlled, rotating outages as a last resort, to prevent uncontrolled blackouts.
The memory of a deadly storm in February 2021 that left millions without power, water, and heat for several days is still fresh in the minds of Texas residents. The incident highlighted ERCOT’s struggle to prevent a grid collapse during extreme weather conditions.
The current heatwave has prompted AccuWeather to forecast temperatures in Houston, Texas, reaching a scorching 107 degrees Fahrenheit (41.7 degrees Celsius) on Thursday, far above the normal high of 94 F (34 C) for this time of year.
ERCOT projects that the demand on Thursday will be around 84,928 megawatts (MW), which is just below the record of 85,435 MW set on August 10. However, reserves are expected to fall short due to potential unavailability of some power plants.
Unlike other grids in the country, ERCOT heavily relies on its own generation as its transmission system has limited interconnections with neighboring systems. This makes it challenging to import significant amounts of power from other regions during times of high demand.
Consequently, next-day power prices at the ERCOT North Hub, including Dallas, spiked to $925 per megawatt-hour for Thursday, compared to $255 for Wednesday. This surge is well above the average prices of $75 so far this year, $78 in 2022, and $66 over the last five years (2018-2022).
In addition to ERCOT, the Midcontinent Independent System Operator (MISO), responsible for serving 45 million people across 15 states from Minnesota to Louisiana, also anticipates resource shortages. MISO declared an energy emergency alert due to extreme heat and unplanned generation outages, although the grid remains stable.
MISO estimates that it will have approximately 125,907 MW of supplies, including 120,656 MW from internal resources and 5,251 MW from imports. However, this might not be sufficient to meet the projected peak of 127,692 MW, surpassing the grid’s all-time high of 127,100 MW in July 2011.
Authorities from both ERCOT and MISO are working diligently with utilities and neighboring grids to ensure the availability of as many resources as possible throughout the day, striving to maintain reliability amid the challenging conditions.