Jun. 19—RED WING, Minn. — A severed cable cost the Prairie Island Nuclear Facility roughly three months of power generation and an estimated $9 million to $12 million in repair costs.

“We estimate the capital cost of the cable replacement to be in the $9-12 million range,” said Theo Keith, spokesman for Xcel Energy. “We estimate that we incurred between $1-2 million of operation and maintenance costs to bring the plant back online.”

The outage occurred in October when teams working at the site inadvertently severed underground cables between the plant and the substation while performing horizontal drilling work to replace a different underground cable. Keith said Unit 1 at the nuclear plant essentially took “itself offline, as it is designed to do.”

“Unit 2 was already offline at that time for scheduled refueling,” he added.

Keith said the $1-2 million cost of bringing the plant back online after the unplanned outage will be paid by Xcel, and the energy company will not be seeking any recovery of costs.

Two other costs from the outage are still up in the air, said Cori Rude-Young, director of Communications & Public Affairs for the Minnesota Public Utilities Commission.

The first is the cost of purchasing power from the grid to replace the power lost by Unit 1 being taken offline. The PUC will determine who pays those costs — Xcel directly and its rate-paying customers or a combination of the two — at a hearing in mid-September 2024. Rude-Young said this cost, estimated at roughly $33.8 million, is the major expense related to the Unit 1 outage, though its exact cost has not been figured because it must be calculated based off how much fuel the nuclear plant would have used, the cost of the fuel and the cost of the replacement electricity.

The cost of repairs to the damaged cable, Rude-Young said, will either fall under operation and maintenance expenses or capital expenditures.

“Capital expenditures will be added to rate base and be reviewed/approved/not approved in Xcel’s next rate case,” she said. “If the repairs are O&M expenses, Xcel cannot recoup those costs as O&M is already set in their current rate case. We anticipate they will file the new rate case later this year and decisions in that prospective rate case will be sometime in the first half of 2026.”

The damaged cable was fixed and Unit 1 was restarted in January. Unit 2 returned to service in March.

However, even with both units out of action, Keith said, Xcel customers continued to receive power from other power sources.

“Service to customers was not impacted by the plant being offline,” he said.