The cold snap that rang in the new year prompted Omaha homeowners to crank up the thermostats, sending gas and electric meters spinning.
Natural gas consumption on the Metropolitan Utilities District system on Dec. 31 was the second-highest ever, and just 2 percent below the all-time daily high notched on Jan. 9, 2010.
Consumption between Dec. 30 and Jan. 2, when temperatures dove into subzero territory, was nearly double that of the same period last year.
“It’s been a tale of two different Decembers. For the first three weeks, we sold about 129,000 decatherms (of gas) a day. The last 10 days, we sold 240,000 per day,” Jim Knight, MUD vice president of gas operations, said Wednesday morning at the gas and water utility’s monthly board of directors meeting.
A decatherm is approximately 1,000 cubic feet of gas or 1 million British thermal units.
Volume skyrocketed to 313,000 decatherms on Dec. 31, by which time the wholesale markets had reacted to heightened demand. Knight said market pricing fluctuated from as low as $2.50 per decatherm in early December to up to $100 on Dec. 28.
MUD crews stayed busy over the holiday weekend, fixing 15 water main breaks to cap a month in which 81 main breaks surpassed the 10-year monthly average of 52 for December. That wasn’t enough to top the all-time December record of 96 water main breaks in 2016, but the district’s increasingly fragile cast iron water mains ruptured 558 times in 2017 — more than in any other year on record.
“Unfortunately, 2017 was a very busy year for us for water main breaks,” said Cory O’Brien, MUD’s vice president for engineering and construction. “Not surprisingly, most breaks throughout the year and last weekend were cast iron mains.”
Natural gas consumption during the spell was more dramatic than electricity consumption because more local homeowners use gas-powered furnaces. Winter electricity demand so far peaked on Dec. 27 at just 2 percent above last winter’s peak, according to preliminary figures from the Omaha Public Power District.
Because of volatile natural gas prices and tight gas supplies, OPPD ran only its fuel oil-powered peaking plants to meet higher electricity demand from Dec. 30 to Jan. 2, said Troy Via, the electric utility’s division manager for energy marketing and trading. Coal consumption over that period was only slightly higher than last year.
Even though coal stockpiles can “freeze” during prolonged periods of extreme cold weather, recent conditions have had only a negligible effect on OPPD operations, according to Gary Ruhl, manager of fuels and technical services.
“The stockpile can get a thin frozen crust layer on top that is broken up and set aside to get at good coal underneath,” and train cars loaded with coal can take “considerably longer” to thaw out in a designated building, Ruhl said.
But that’s not out of the ordinary.
“All in a day’s work for power generation,” he said.
The cold magnified problems that are fueling MUD’s 20-year capital project to remove or abandon more than 1,700 miles of aging cast iron gas and water mains across its service territory. It’s on track to replace 11 miles of water mains and about 40 miles of gas mains in 2018.
Between now and the time MUD replaces the last of its cast iron mains in 2027, it will have spent $1 billion on water mains alone.
Despite the annoyance of having no access to water for a few hours in the event of a main break, broken water mains pose a lesser risk than ruptured gas mains. Accordingly, U.S. utilities have been allocating hundreds of millions, if not billions, of dollars annually to address gas mains.
Federal regulators in 2011 issued a “call to action” for those companies to update infrastructure during a 13-month period in which three explosions and fires killed seven people and injured several others in Texas and Pennsylvania. Investigators faulted cast iron gas mains that had deteriorated or otherwise failed to the point of catastrophe in each incident.
MUD has so far avoided any such catastrophes related to broken cast iron gas lines — the January 2016 M’s Pub conflagration was due to a line that was hit by a directional boring machine — and utility President Scott Keep said the safety record is due in part to the district’s focus on “targeting our worst pipe first.”
Said O’Brien: “At this point, our infrastructure replacement efforts have gotten a lot of traction and a lot of that old cast iron (gas main) is gone. I think we had five breaks in December for gas, and we’ve taken so much of that old pipe out of the system (that) there’s just not that much left to break.”