News

U.S. Electric Companies Brace for Extreme Winter Weather

A large part of the central and eastern U.S. was hit with some of the coldest weather in decades on Jan. 6 and 7.

A polar vortex—a large low-pressure area that normally spins in central parts of Canada circulating air up through the North Pole—dislodged and came down into the mid-section of the U.S. With it came some of the coldest temperatures seen in some areas since the 1990s. As far south as Atlanta, Ga., lows were expected to reach 6F. Fargo, N.D. was expected to see much worse, with temperatures reaching –31F and wind chills as low as –60F. Weather like that wreaks havoc on power plants not used to dealing with the extreme temperatures.

According to Mark Julian, vice president of FirstEnergy utility operations, “FirstEnergy crews began focused cold weather inspections and assessments last week to confirm our equipment is in peak condition and minimize potential challenges the extreme weather may pose.” The company verified oil and pressure levels in breakers and transformers, ensured proper operation of heaters on breakers and critical substation equipment, and confirmed spare fuses and other replacement parts were on hand.

Anticipating that the artic cold wave would produce high demand for electricity, the Tennessee Valley Authority (TVA) issued a “Conservative Operations Alert” on Jan. 3, which suspends all non-essential maintenance activities to minimize the risk of power interruptions at TVA generation facilities. The company reported a peak power demand of 32,460 MW at 9 a.m. eastern standard time (EST) on Jan. 7, which was the second highest winter peak in TVA history, 112 MW less than on Jan. 16, 2009.

“While we are confident in the reliability of our system, we are monitoring the forecast very closely,” said Randall Pinkston, distribution manager for Mississippi Power, a subsidiary of Southern Company. “In addition to our normal shifts, we will have an additional crew scheduled to work in non-routine hours in the event of power outages.”

Duke Energy officials asked Carolina customers to focus on conserving energy during the cold spell. The company also asked customers to turn off as many appliances and electronics as possible, if power were to be lost, in order to reduce the immediate demand on the system when electric service is restored.

Compounding electric system challenges in the Northeast, two nuclear units were forced offline in the past 24-hours. Beaver Valley Power Station Unit 1 automatically tripped from 100% power due to a main transformer differential trip on Jan. 6 at 4:59 p.m. EST. A few hours later, at 9:15 p.m. EST, Indian Point Unit 3 experienced an automatic reactor trip from 100% power due to a steam flow to feed flow mismatch. All safety systems worked as designed. There was no release of radioactivity and no threat to the safety of workers or the public in either case.

The weather is also dramatically affecting natural gas prices, particularly in the Northeast. Platts oil and gas analytics unit, Bentek Energy, said that U.S. natural gas demand hit a new record on Jan. 7, reaching 134.3 Bcf/d. The U.S. Energy Information Administration noted that all natural gas pipelines into New England from the west and south were constrained. Natural gas prices traded on Jan. 6 for next day delivery were near $40/MMBtu in both New England and New York City. Critical notices were declared on two pipelines—Algonquin and Tetco—requiring hourly scheduling from generators.

In the Great Lakes region, lake effect snow was predicted to be very heavy. Lake effect snow results when very cold air flows over the relatively warm waters of large lakes. Intense evaporation from the lake surface forms convective clouds that organize into bands of snow showers when they reach land. Buffalo, N.Y. is notorious for receiving lake effect snow off of Lake Erie, and could receive as much as two feet during this winter storm. North of Syracuse, N.Y., some of the heaviest snow is expected to fall east of Lake Ontario, with totals up to 72 inches predicted.

Aaron Larson, associate editor (@AaronL_Power, @POWERmagazine)

SHARE this article