DENVER (AP) — A coal-fired power plant in Colorado has faced operational, equipment and financial problems that have led to more than 700 days of unplanned shutdowns since 2010, regulators said in a report.

The report by the Colorado Public Utilities Commission questions performance at the Pueblo plant operated by Minneapolis-based Xcel Energy Inc., The Colorado Sun reported Wednesday.

The report found the cost of electricity at the plant was 45% higher than projected, reaching $66.25 for each megawatt-hour. It also said annual operating costs were 44% above forecasts, hitting $34.8 million a year.

“We are closely reviewing the Colorado Public Utilities Commission’s report on Comanche Unit 3 in Pueblo. Meanwhile, we are committed to the continued safe and reliable operation of the plant through its proposed early retirement in 2040,” Xcel Energy said in a statement.

The utility, which is Colorado’s largest electricity provider with 1.5 million customers, said it’s looking for new ways to learn and improve the way it runs its facilities.

The problems come as utilities nationwide are turning away from coal-fired electricity in favor of cheaper and cleaner natural gas and renewable energy.

The commission did the review after two mechanical failures closed the plant all of last year and part of this year. The first failure started in January 2020 and lasted until June while repairs and inspections costing more than $4 million were done.

When trying to restart, there was a failure in a key valve that led to a loss of lubricating oil used to keep elements of the turbine from overheating, the report said. The valve was obsolete, so there was no way to purchase replacement parts.

The second failure cost $20 million and forced the company to spend $14 million in replacement power.

Xcel Energy’s statement said it’s proposing to run the plant at a significantly reduced capacity after 2030, using it as a backup to renewable energy generation that isn’t able to meet demand.

The two failures last year were the latest in a host of problems since the $1.3 billion unit went into service in 2010.

The report outlines several unplanned outages, adding up to more than 335 days of unplanned shutdowns between 2012 and 2019.

As a result, Xcel Energy said it will close the plant in 2040, about 30 years earlier than planned as part of its Clean Energy Plan aimed at producing zero-carbon electricity by 2050.