By Tom Kleckner
ERCOT released its final winter assessment Nov. 2, indicating it has more than sufficient generation to meet an anticipated peak demand of 57,400 MW. The Texas grid operator says it has more than 79,000 MW of generation resources available.
ERCOT’s final winter Seasonal Assessment of Resource Adequacy (SARA) focused on expected reliability scenarios for December through February. It reflects forecasted expectations based on customer demand experienced during recent cold-weather events and current expectations for average weather this winter.
Warren Lasher, ERCOT’s director of system planning, said the grid expects to meet winter demand “across a broad range of operating conditions and weather scenarios … even during high-load conditions with extreme generation outages.”
ERCOT’s senior meteorologist, Chris Coleman, told reporters during a conference call that he is forecasting wetter-than-normal conditions for December and January, based on an El Niño winter pattern that “has an opportunity to be the largest on record.” In Texas, he said, that will result in cloudy weather, leading to milder overnight temperatures and morning lows.
“If, as expected, El Niño backs off in intensity by February,” Coleman said, “we could see a late-season cold pattern that drives temperatures lower across the ERCOT region.”
In February 2011, severe cold weather and unexpected plant outages forced ERCOT to call for rolling blackouts. While the grid’s reserve margin has increased since then, ERCOT has also taken other steps to minimize a repeat occurrence.
“We’re more prepared for winter-weather issues than we have been in the past,” said ERCOT spokesperson Robbie Searcy. “We’ve been spending more time on site visits and working with generation owners on their winter plans.”
The grid has also added nearly 1,100 MW of resource capacity from mostly wind projects since its preliminary winter SARA, issued in September. (See ERCOT Expects Sufficient Generation for Fall, Winter.) It said several units previously in seasonal-mothball status have returned to service and several new resources have become operational.
ERCOT last week also released its preliminary SARA for next spring, based on average springtime weather conditions over the past 13 years. The study’s results indicate the grid will also have sufficient installed capacity to meet forecasted peak demands during March-May 2016.
The grid operator estimates 1 MW of demand is typically enough to power about 500 homes during mild weather conditions and about 200 homes during summer peak demand.
