This summer, temperatures in Texas have been significantly higher than average, with record-breaking ERCOT demands and Real-Time prices reaching their maximum cap on multiple days in both June and August. In fact, between June and August, ERCOT eclipsed the 2022 maximum demand of 80,148 MW on 47 different days, with this summer’s maximum of 85,464 MWs set on August 10. Figure 1 shows the effect of the record breaking heat on spot electricity prices in North Texas in the months of June through August,
With growing energy demand in Texas, there is a need for more power-generating resources to maintain the grid's reliability and to ensure there is a balance between available power supplies and demand. Intermittent sources like wind and solar cannot be dispatched on-demand, making it unreliable during hours when electricity supplies are tight.
This summer, the grid’s vulnerability to insufficient reserve margins was demonstrated multiple times after the sun set, solar output dropped to zero, and wind output was low due to insufficient wind speeds across the state. Ancillary services are ERCOT’s market mechanism to ensure that power-generating assets are on standby and available to produce electricity on days when solar and wind outputs are low and demand on the grid is high.
Before this summer, there were four market-procured ancillary services: Regulation Up, Regulation Down, Responsive Reserve Service, and Non-Spin Reserve Service. A few years ago, ERCOT and the Public Utility Commission (PUC) decided these four services were insufficient to provide adequate levels of responsive reserves. To address this need, ERCOT added a fifth ancillary service, the first to be added since the market opened in 2002, called ERCOT Contingency Reserve Service (ECRS), which went into effect on June 10, 2023.
ECRS can be seen as an intermediate product between Non-Spin and Responsive Reserve capacity that can respond within 10 minutes to address operational issues. These services secure additional power capacity beyond regular supply and are purchased in the Day-Ahead Market. This new ancillary service is intended to address unforeseen disruptions like generator failures or sudden demand spikes and to provide a rapid response backup to the grid. These contingency reserves are provided by power plants (or other resources such as load) that are capable of quickly ramping up their generation (or reducing their consumption) to help balance the grid during times of reduced reserves.