- The Electric Reliability Council of Texas (ERCOT) does not anticipate the need to impose rotating outages due to summer peak conditions, despite the risk posed by historically low reserve margins, according to forecasts released by the grid operator on Tuesday.
- ERCOT expects an increased chance of energy emergency alerts, given the large electric use predicted in its preliminary assessment of June through September 2019. Declaring an alert gives ERCOT access to resources restricted to conditions of scarcity, such as demand response products, calls for voluntary conservation and additional generation.
- "At this point, we have no specific indication" that rotating outages would be needed this summer, Dan Woodfin, senior director of system operations at ERCOT, said on a media call. But this forecast could be impacted by factors such as extreme weather and high demand, he added.
ERCOT's current planning reserve margin for the summer is at 7.4%, nearly half of the state's target of 13.75%. The low reserve margin dropped to this expected level after a municipal utility informed the grid operator in January about its plans to purchase cheaper energy on the open market this summer, mothballing its 470 MW Gibbons Creek coal plant.
The preliminary version of ERCOT's summer 2019 Seasonal Assessment of Resource Adequacy (SARA) does not indicate the need for brownouts, or rotating outages — the grid operator's last resort under the energy emergency alert program.
"Although, having reserves at this level does increase the likelihood that [rotating outages] could be needed if we have extreme weather or above-normal forced outages of generators, or very low wind output or very high demand on a particular day," Woodfin said.
When benchmarked against the weather in 2011, the most extreme conditions that the grid operator faced in recent history, the summer 2019 SARA report showed a range of potential risks requiring more reserve capacity than the 3,301 MW forecast to be available.
While it's "still too early to forecast what type of peak load conditions" will be experienced, the 2011 estimate includes drought conditions that are not anticipated this summer, Peter Warnken, resource adequacy manager at ERCOT, said Tuesday on a media call.
The grid operator would take "measures to maintain operating reserves at a level that support grid reliability" following an energy emergency alert, Warnken said.
First, ERCOT would fully utilize available generation capacity, and then "if necessary, we'd deploy contracted emergency resources as well as demand response programs," he said.
According to Woodfin, the demand response programs' capacity forecast for this summer includes:
- Approximately 900 MW available through the emergency response service (ERS) program, the demand response program administered by ERCOT;
- Between 200 and 300 MW from load management programs set up by utilities with their consumers; and
- "Anywhere from 1,100 to 1,500 MW," according to Woodfin, from large industrial facilities that can manage their grid load during hot periods, based on 2018 data.
The ERS is procured on a seasonal basis, expected to be locked down in mid-to-late May for the summer session, while ancillary services would be procured daily in ERCOT's day-ahead market.
Demand response programs between retail energy providers and their consumers might exist as well, but ERCOT does not monitor them, Warnken said.
The grid operator would also request support during energy emergencies from ERCOT's neighboring grid and make voluntary calls for public conservation, he added.
"We aren't generally planning on requesting conservation unless it's absolutely necessary to maintain reliability," Woodfin said.
In January, ERCOT implemented a change to its operating demand reserve curve, under the direction of the Public Utility Commission of Texas (PUCT), to increase power prices as the system begins to encounter capacity scarcity conditions. "This is expected to help incentivize generation owners and developers to provide more capacity for the ERCOT market," Warnken said.
The final spring 2019 SARA, also released Tuesday, included estimates of delayed generation projects, including approximately 500 MW of wind primarily in West Texas and the Panhandle. The delays are "not uncommon" or greater than observed in the past, and are reported by developers for various reasons, Warnken said, with "delays of several months up to a year."
ERCOT expects 162 MW of new wind and 172 MW of new solar capacity this summer.
The grid operator is seeing solar and wind development in West Texas, as well as interest in pairing with battery storage technology, although "a lot of these projects are in the early study phases," Warnken said. He added that there's interest in smaller gas peaker units, while large combined-cycle projects have been postponed as "developers are looking at the future market conditions."
More generation might exist in the region from small distributed systems.
ERCOT staff is compiling the results of a survey of distributed generation, focused on non-opt in entities, Warnken said, "to get a better handle on what might be out there," specifically regarding small facilities such as rooftop solar. The survey is in response to a request from the PUCT to calculate available distributed power in the state.