ERCOT expects tight reserves for summer

Generation capacity for the Texas grid is expected to be tight this summer, according to a preliminary summer assessment released March 1 by the Electric Reliability Council of Texas.

“Based on the National Weather Service’s three-month outlook, we are expecting above-normal temperatures this summer – though not as extreme as last summer’s,” said Kent Saathoff, ERCOT’s vice president of grid operations and system planning. “If that’s the case, we expect to be able to meet the peak demand on the grid, unless we have above-normal generation outages.”

Initiatives are under way to increase voluntary demand reduction during peak summer hours, Saathoff said.

“We are working with the Public Utility Commission to increase our load management options – or voluntary interruptible load that is paid to be curtailed in an emergency situation,” he said. “These are typically a mix of large industrial companies, but we’re now including smaller industrial and commercial companies and trying to facilitate the ability for these smaller customers to aggregate their load for this emergency interruptible load service.”

The projected summer peak demand has been increased to 67,492 megawatts – 1,297 MW higher than would be expected with “normal” summer temperatures, based on the Climate Prediction Center’s 40% chance of hotter-than-normal weather for summer. The new forecast is 887 MW less than ERCOT’s all-time record-peak demand of 68,379 MW, which occurred Aug. 3, 2011, during extreme weather conditions.

“If we have a higher-than-normal amount of generation outages or if we experience record-breaking electricity demand because of extreme temperatures – like we had last summer – we may have to ask the utilities to initiate rotating outages to protect the grid from a state-wide blackout,” Saathoff said.

“Overall, we expect our reserves may get low enough to put us into the initial stages of our emergency procedures on some days, but not necessarily rotating outages,” he said.

Consumer conservation can play an important role, he noted.

“Although we implemented emergency procedures on six days last August due to low reserves, the consumers and businesses helped us reduce the demand by responding to our requests for conservation,” Saathoff said.

Recent rains have improved the drought conditions for the near term, Saathoff said.

“We don’t anticipate the drought to be a major factor this summer, but we will continue to monitor how it’s affecting capacity due to its impact on cooling water resources available for generation units,” Saathoff said. The recent rains have improved the current situation and, given our latest information, we don’t expect to have significant generation loss due to the drought this summer.”

In addition to the load management options, ERCOT said it is working on a number of other initiatives to address capacity shortages for the short term.

The ERCOT board recently approved a process governing ERCOT’s use of emergency authority to recall idled units for capacity. Approximately 2,600 MW is currently mothballed; including about 1,500 MW that could be returned to service with one to four months notice.

ERCOT will release its next summer assessment in early May.