HOUSTON, Jan 7 (Reuters) - PJM Interconnection, the power grid agency for the mid-Atlantic and parts of the Midwest, took emergency steps to meet surging demand as subzero temperatures forced power plants to shut, grid officials said on Tuesday.
The National Weather Service warned that temperatures were expected to be 25 degrees to 35 degrees Fahrenheit below normal (minus 14-19 Celsius) from the Midwest to the Southeast.
"This particular cold is far-reaching and most of our neighbors are experiencing the extreme conditions we are," said
Michael Kormos, PJM executive vice president for operations.
Real-time power prices in PJM ran about $1,000 per megawatt-hour at midday, according to the PJM website, after climbing above $1,500 per MWh earlier in the day.
Kormos said a large number of power plants in the region stretching from Delaware to Ohio to Tennessee were struggling to operate in the harsh sub-freezing temperatures.
PJM has asked consumers to curb power use as demand rises later Tuesday to avoid potential rolling outages.
Kormos cited weather-related mechanical failures and natural gas supply problems, as well as normal generation issues, for power plants being knocked offline Tuesday.
"We've had some fuel interruptions on the natural gas system where units have not been able to get fuel," Kormos told reporters on a call. "We've had units trying to convert to back-up fuel that were not successful starting up."
"We've seen everything," Kormos said.
Grid officials were in contact with gas pipeline operators, Kormos said.
PJM issued an alert Monday to warn power-plant operators that system conditions would require them to be available to meet soaring demand.
Plant operators brought plants back online as quickly as possible, making it difficult for PJM to quantify the number of units, or total generation, offline, Kormos said.
"The units have been asked to run an extra long time with the cold we've been seeing," he said.
PJM ordered a systemwide 5 percent voltage reduction on Monday evening to conserve power, but did not repeat the call Tuesday, Kormos said.
Even with demand response programs, which pay customers to reduce use in times of high demand, the region set a winter electric use record of 138,600 MW early Tuesday, surpassing a 2007 record of 136,000 MW, officials said.
Kormos said PJM expects to meet the afternoon peak demand, but needed public conservation.
"We're very close and it may just be that last couple hundred megawatts (saved) that allow us not take any forced interruptions."
PJM oversees electric markets serving all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia and the District of Columbia.
PJM members include units of American Electric Power Co , FirstEnergy Corp, Exelon Corp, Public Service Electric & Gas Co and others.