ERCOT cautions Texans to save power
Higher-than-anticipated power plant outages and temperatures caused electricity supplies to be tighter than forecast Tuesday, forcing the state’s grid manager to call on power customers to conserve energy.
Wholesale power prices soared as high as $2,000 per megawatt hour as the supplies shrunk late Tuesday afternoon, nearly 100 times higher than earlier in day, when electricity was selling for about $25 a day. The Electric Reliability Council of Texas, or ERCOT, ended the appeal for conservation measures at about 8:45 p.m. Tuesday.
Power plants are typically shut down for maintenance between February and May to prepare for the summer when demand for air-conditioning — and power — skyrockets with rising temperatures. ERCOT officials said supplies could again become unusually tight in coming weeks as the planned maintenance shutdowns continue.
“These (power plants) are big complicated machines,” said Woody Rickerson, ERCOT’s vice president of grid planning and operations. “They require maintenance. You can’t run them continuously.
“There may be days like today where (power) margins are tighter than we like,” Rickerson added. “We could be in the same situation in the next few weeks.”
ERCOT’s warning to conserve electricity surprised many Texans still on edge after the February winter storm, which iced over natural gas wells, froze wind turbines and tripped off power plants.
At that time, the grid operator was forced to order rotating outages that led to nearly 200 deaths and billions of dollars of property damage from broken pipes.
The warnings also called into question ERCOT’s announcement less than a month ago that it expects to have enough power on hand to meet another record summer demand.
Although ERCOT warned power supplies might be tight over the next few weeks due to scheduled plant outages, it stood by its summer forecast on Tuesday.
ERCOT found itself in a bind Tuesday after a cold front that was expected to blanket much of Texas with cooler temperatures did not materialize, putting higher-than-anticipated demand on the state’s power grid.
The grid operator said its customers were using about 48,000 megawatts of power to cool their homes as temperatures hovered around 80 degrees on Tuesday evening.
At the same time, ERCOT had about 32,000 megawatts — enough to power 6.4 million Texas homes on a hot day — of its more than 80,000 megawatts of total power capacity offline due to maintenance on Tuesday.
The outsized demand and idled generating capacity shrunk power reserves to about 1,000 megawatts early Tuesday evening, ERCOT said.
“We don’t like to have tight margins,” Rickerson said. “If we didn’t do maintenance, we would have more trouble. We need to allow for maintenance.”
ERCOT said it typically has between 20,000 and 30,000 megawatts of power capacity out for maintenance every April.
This year, there is slightly more power capacity offline — an additional 4,000 megawatts — in part due to ongoing repairs from the winter storm and other unforeseen outages.
Planned maintenance is scheduled as far as nine months back, Rickerson said, and power plants undergoing maintenance cannot easily be called back into service.
Complicating matters, solar farms in Texas were producing about 3,000 megawatts less power than usual as cloudy conditions blanketed much of the state, ERCOT said.
Wind farms produced 8,000 megawatts of power on Tuesday and are expected to produce 7,000 megawatts of power on Wednesday, well below the usual 11,000 megawatts for this time of year, according to Enverus, an Austin energy research firm.
ERCOT issued a conservation alert early Tuesday evening, calling on consumers to conserve power to prevent damage to the power grid.
The conservation watch is issued when there are less than 2,500 megawatts of power supply remaining to meet demand.
The grid operator was prepared to put small generators to work, pay industrial users to turn off their operations and if need be, to issue more conservation warnings. By 7:30 p.m. however, ERCOT said it had enough power to meet demand.