Xcel Energy representatives met Thursday with state regulators in a closed-door session to discuss last weekend’s power outages.
Officials said the informal meeting generated many questions and few answers.
“We asked a lot of questions, and they had a lot of answers that were, ‘We don’t know yet,”‘ said Jim Greenwood, director of the Office of Consumer Counsel, a state agency that represents consumers in utility issues.
Pending a formal report that Xcel will provide by March 10, the Colorado Public Utility Commission could launch a formal investigation into the outages and their cause.
“We take it very seriously,” said Terry Bote, a spokesman for the PUC. “When you have your largest utility with an outage on the coldest day of the year, that’s a serious situation.”
The cold-weather-induced outages left about 325,000 Colorado customers of Xcel without power for periods of 30 minutes to several hours Saturday.
Xcel has blamed the outages on a combination of colder- than-expected weather, a temporary shortfall of natural-gas supplies and the breakdown of some coal-fired generators that stressed the ability of gas-fired units to make up the difference.
When it became apparent Saturday morning that Xcel would not be able to generate enough power to serve all customers, the utility started a series of three planned outages, each affecting about 100,000 customers for 30 minutes. About 25,000 customers were without power for periods of up to several hours – because of either unrelated problems or Xcel’s difficulty in restarting service after the 30- minute planned outages, utility officials said.
“It was a real pain,” said Arvada resident David Stockwell, whose home was without power for four hours.
Like most homeowners, Stockwell was left with no heat because most systems use electricity to run blowers or pumps that distribute natural-gas-fueled heat.
“The temperature (in the home) finally got so low that we had to start a fire,” Stockwell said.
Sun Microsystems’ Storage Tek division was hit by the rolling outages over the weekend, resulting in a need for the Louisville-based operation to upgrade its energy-backup plans.
“It was very painful,” said Sun chief information officer Wil liam Vass in Boulder on Thursday. “That’s an area where we need some upgrades at the StorageTek site to have it have generator backup, because it didn’t, so it could only stay up for about 30 minutes, and that was a problem.”
Xcel said it will conduct an internal investigation to prepare its report for the PUC. The investigation will be headed by Bob Hix, an Xcel executive who served as a commissioner and chairman of the PUC from 1994 to 2001.
Unlike in previous years, Xcel will face no financial penalties this year for power outages.
Until 2006, Xcel reported the duration of power outages to state regulators, and if the total exceeded a predetermined threshold, Xcel was assessed financial penalties.
For example, the utility was penalized $13.6 million for exceeding 2005 outage limits. The penalty will appear as a credit of $11.33 per customer in June’s utility bills.
However, in a utility-case settlement reached last year among Xcel, the PUC and other parties, Xcel agreed to invest $11 million in electric-system reliability in lieu of any outage penalties for 2006.
Rolling power outages are virtually unheard of in winter months. They typically occur during the hottest days of summer when demand for air-conditioning exceeds the capacity of generation and transmission equipment.
Xcel said a rare combination of factors coalesced to cause the power disruptions. Among them:
Friday-night and Saturday- morning temperatures on average were 15 degrees colder than forecast. Xcel said natural-gas supplies and gas-fired power capacity probably would have been adequate had temperatures remained at forecast levels.
Xcel experienced mechanical problems at two of its coal- fired power plants just before the frigid temperatures hit. Had the coal generators not failed, Xcel said, power supplies would have been sufficient.
Regional gas pipelines were operating at full capacity because of the cold weather, preventing delivery of additional supplies.
“There currently is a lot of natural gas in storage,” said Paul Wilkinson, an executive with the Washington-based American Gas Association. “But moving gas into your region could have been a problem with pipeline capacity.”
Staff writer Kimberly Johnson contributed to this report.
Staff writer Steve Raabe can be reached at 303-820-1948 or sraabe@denverpost.com.
