Entergy seeks approval for Waterford 3 uprate

Waterford 3 is a pressurised water reactor that began commercial operation in 1985 and currently has a net electrical output of about 1,150 MWe. It has a licence from the US Nuclear Regulatory Commission to operate until 2044. Entergy is considering a subsequent licence renewal to extend the plant's operation to 2064.

In its application to the Louisiana Public Service Commission (LPSC) to uprate the plant, Entergy Louisiana LLC (ELL) noted it is "projected to need additional long-term generating capacity over the course of the long-term planning horizon to replace deactivated capacity and address load growth in order to reliably serve customers." It added: "Nuclear generation is an important part of the resource portfolio that ELL has deployed to reliably serve its load and meet planning obligations. It provides clean, economic baseload capacity and contributes to fuel diversity in ELL's portfolio. More specifically, ELL's Waterford 3 in Killona and River Bend Nuclear Station in St Francisville are the largest sources of carbon-free power in Louisiana."

During a refuelling outage earlier this year, three low-pressure turbine rotors that "were nearing the end of their useful life" were replaced at Waterford 3. Entergy said the uprate project is "composed of a number of plant modifications that will allow increased electrical output resulting from the higher efficiency of those new low-pressure turbine rotors."

Entergy said most of the uprate work - which will increase the plant's capacity to about 1,195 MWe - would be carried out during the reactor's scheduled refuelling outage in late 2026, with the remainder carried out in late 2029.

"The power increase can be obtained using the same thermal output from the reactor, meaning that the increased electrical output is expected to be achieved with no increase in fuel costs at the plant," Entergy noted.

According to Entergy's economic analysis, the upgrade is expected to generate a net present value benefit of USD205 million for customers, driven by increased energy sales and federal tax credits, The Center Square reported. The company projects USD11.2 million in energy savings and USD13.1 million in production tax credits in the first full year of operation, assuming the project comes online as scheduled in late 2026.

Entergy is counting on production tax credits under Section 45Y of the Internal Revenue Code, recently preserved for nuclear uprate projects in the federal One Big Beautiful Bill Act signed in July. While eligibility is still subject to Internal Revenue Service guidance, Entergy said the credits alone could offset the full cost of the project to customers.

Capacity uprates and licensing extensions to existing nuclear plants are specifically mentioned in the raft of executive orders signed on 23 May by President Donald Trump, seeking to reinvigorate the US nuclear energy sector and quadruple nuclear generating capacity by 2050.