Duke Energy said it plans to decommission its retired Crystal River Nuclear Plant in Florida by 2027, nearly 50 years sooner than originally scheduled.

The accelerated decommissioning plan is subject to approval by the U.S. Nuclear Regulatory Commission and the Florida Public Service Commission. The process will take about a year to complete. If approved, decommissioning work would begin in 2020 and end in 2027.

The shuttered Crystal River nuclear plant is adjacent to a coal-fired unit that also is being retired. Credit: Duke EnergyThe shuttered Crystal River nuclear plant is adjacent to a coal-fired unit that also is being retired. Credit: Duke EnergyDuke Energy previously announced its decision to retire the plant in February 2013, and to decommission it by 2074.

To perform the work, Duke Energy has contracted with Accelerated Decommissioning Partners, a joint venture between NorthStar Group Services and Orano USA.

So long, Pilgrim

In a separate development, control room operators at Entergy’s Pilgrim Nuclear Power Station in Massachusetts shut down its reactor for the final time on May 30. The company said its decision to shut down Pilgrim was the result of a number of financial factors, including low wholesale energy prices.

Pilgrim Nuclear employs about 600 people and had a generating capacity of 680 megawatts. It entered service in 1972. Entergy purchased the plant in 1999 from Boston Edison.

The Pilgrim nuclear power plant in Massachusetts shortly after it opened in 1972. Credit: energy.gov. The Pilgrim nuclear power plant in Massachusetts shortly after it opened in 1972. Credit: energy.gov. In August 2018, Entergy proposed selling the business unit that owns Pilgrim to a Holtec International subsidiary, a decommissioning company that plans to complete decommissioning at the site decades sooner than if Entergy continued to own the plant. Regulatory approval and closing of the transfer are targeted for 2019.

Entergy’s remaining operating nuclear power plants in merchant power markets - Indian Point Unit 2 and Unit 3, in New York, and Palisades Power Plant, in Michigan, are scheduled to be shut down in 2020, 2021, and 2022, respectively. These closures, along with the sale of these plants to decommissioning specialty companies, mark the end of Entergy’s participation in merchant power markets and its return to a pure-play utility.

Plant troubles

The Crystal River reactor went offline in September 2009 for refueling, once through steam generator replacement and 20% power up-rate outage. In preparing the containment building to replace the two steam generators, tendons in the containment building wall were detensioned. Workers discovered a large gap in the concrete of the containment building wall. The main cause of the delamination was attributed to the scope and sequence of the tendon detensioning.

After analyzing options, Duke Energy announced in February 2013 that the Crystal River Nuclear Plant would be permanently shut down. Duke Energy said it is now pursuing accelerated decommissioning at Crystal River for two reasons.

First, it said that the trust fund that pays for the decommissioning is currently sufficient to accelerate the plant’s decommissioning without increasing customer bills. The trust fund had about $717 million as of March 31, 2019.

Second, Duke Energy has completed the initial phase of decommissioning, placing the plant in a condition to attract bidders to complete the work. This progress, coupled with increased competition in the industry, has lowered decommissioning costs, the utility said, making the accelerated model financially feasible.

Contract terms

If regulators approve the transaction, Duke Energy will remain the Nuclear Regulatory Commission-licensed owner of the nuclear plant, property and equipment and retain ownership and control of the trust fund that pays for the decommissioning.

In turn, Accelerated Decommissioning Partners will become the Nuclear Regulatory Commission-licensed operator responsible for decommissioning the plant in compliance with state and federal regulations. Accelerated Decommissioning Partners will also own the dry cask storage system assets, including the used nuclear fuel assemblies, and operate and maintain the on-site dry cask storage facility.

A dry cask storage facility is self-contained and stores used nuclear fuel assemblies in steel canisters housed in large concrete structures without power supplies, cooling water, pumps or motors. The system is licensed by the Nuclear Regulatory Commission.

Crystal River Energy Complex

The nuclear plant is located at Duke Energy’s 5,100-acre Crystal River Energy Complex on Florida’s Gulf Coast about 85 miles north of Tampa. The complex is home to the new Citrus Combined Cycle Station, two operating coal-fired units and two retired coal-fired units.

In a separate agreement, Duke Energy hired NorthStar Group Services, joint owner of Accelerated Decommissioning Partners, to dismantle the coal-fired units, which formally retired Dec. 31, 2018.

Dismantling the coal-fired units is expected to start in 2019 and finish in 2023.