Colorado utility regulators want to know why a generator in the state’s largest coal-fired power plant has been shut down for two weeks — and they ordered the plant’s operator to tell them as soon as possible.
The Colorado Public Utilities Commission on Wednesday ordered Xcel Energy, the operator, to provide a report explaining why the coal-fired generator — the state’s newest — stopped operating Feb. 3 and whether the shutdown could affect service for customers.
In a letter to commissioners, Brooke Trammell, Xcel’s vice president of rates and regulatory affairs, said the outage was triggered by electrical problems and will not affect the system’s reliability. She added that workers would have to disassemble the generator.
Xcel Energy spokesperson Michelle Aguayo told CPR News in a statement the generator was being repaired. She did not answer questions about when the company expected the generator to be running again.
“Crews are currently working to assess the extent of the issue and begin the repairs needed,” Aguayo said. “The company will cover the potential incremental costs of any additional replacement energy needed to serve our retail customers.”
The February outage is the latest in a long history of unexpected breakdowns and cost overruns for the Comanche 3 generator, which opened in 2010 and cost more than a billion dollars to build. The shutdown also comes as the Public Utilities Commission prepares to announce the closing date for the Comanche station and the end of Xcel’s coal operations in the state.
Commissioner John C. Gavan asked Xcel to provide an incident report as soon as possible, according to a recording of the commission’s meeting. Utilities usually have up to 30 days to provide such reports. He declined to comment for this story.
A commission investigation released last year found the generator was shut down for nearly two cumulative years since it started service in 2010, dropping the plant’s capacity and pushing energy costs 45 percent higher than original estimates. Regulators in May 2020 approved Xcel’s request to recoup $11.7 million in repair costs from customers.
The investigation showed that poor maintenance and human error caused two shutdowns throughout 2020 and cost tens of millions of dollars to repair. According to testimony at a regulatory hearing in December, unexpected outages continued to occur last year, including a tube leak and damage from a snake crawling into a transformer.
Xcel is proposing to close the plant by the end of 2034 to keep in line with the state’s greenhouse gas reduction targets for the company. Environmental groups, including the Sierra Club and Western Resource Advocates, have pushed the company to close it as soon as possible, if not by the end of the decade.
The Public Utilities Commission is expected to announce a closing date for the Comanche Generating Station in the coming weeks.
Editors note: This story has been updated with new information on the cause of Comanche 3’s shutdown.
