US reactor tests boost case for 80-year lifespans as prices bite
As wholesale price pressure spurs demand for 80-year reactor licences, operators and government agencies are combining critical system tests with monitoring advances to prove the safety and business case.
Faced with intense power market competition, an increasing number of U.S. nuclear plant operators are looking to maximize returns on assets by extending reactor lifespans to 80 years.
In July, Exelon Generation submitted a Subsequent License Renewal Application (SLRA) for 80-year operations of its 1.3 GW Peach Bottom 2 and 3 boiling water reactors (BWRs) in Pennsylvania. In January, Florida Power & Light Co. (FPL) submitted the nuclear industry's first-ever SLRA, for two 800 MW pressurized water reactors (PWRs) at its Turkey Point nuclear facility. The Nuclear Regulatory Commission (NRC) plans to issue a decision on the Turkey Point SLRA in 2020.
Dominion Energy also plans to apply for an 80-year operating licence for its 840 MW Surry 1 and 2 reactors in 2019 and its 950 MW North Anna 1 and 2 reactors in 2021, according to the NRC.
Operators and nuclear industry groups have been working with government agencies to prepare the ground for license extensions.
Site-specific and industry-level research into key metals materials and reactor systems are supporting the case for longer operations, industry participants told Nuclear Energy Insider.
Going forward, advanced in-depth monitoring and maintenance innovations will be key to ensuring safety and minimizing costs, they said.
As test results boosts confidence in longer operations, more SLRAs may be on the way, Jason Remer, director of life extension and new technology at the Nuclear Energy Institute (NEI), said.
“Over half of the nuclear fleet has expressed interest in also submitting 80-year license renewals,” Remer said.
Operators choosing to apply for 80-year licences point to significant cost savings compared with building replacement plants.
Rising costs for the Vogtle 3&4 plant in Georgia, the only U.S. nuclear plant under construction, underline the challenge in controlling new build costs. Earlier this year, cost estimates for the 2.2 GW plant rose by $2.2 billion to $27 billion, more than double the original estimate.
For Florida’s FPL, the SLRA for Turkey Point units 3 and 4 would "allow the units to operate until 2052 and 2053 and save FPL customers billions of dollars by avoiding the need for other more expensive power generation,” a company spokesperson told Nuclear Energy Insider.
US average nuclear generating costs in 2017 ($/MWh)
Source: Nuclear Energy Institute (NEI)
The nuclear energy industry has also worked with the NRC to accelerate the SLRA process and reduce application costs, Remer noted.
This has shortened the SLRA process from 22 to 18 months and has reduced costs by an estimated "$1.7 million per application,” he said.
The profitability of nuclear reactors depends on site-specific characteristics such as plant capacity, and the market in which they operate. Operators in Illinois, New Jersey and New York have been boosted by state-level support measures and the Trump administration has also pledged to support continuing operations by seeking ways to protect plants against wholesale market pressures.
“Impending retirements of fuel-secure power facilities are leading to a rapid depletion of a critical part of our nation’s energy mix, and impacting the resilience of our power grid,” the White House said in June.
Forecast margins for operational US reactors
(Click image to enlarge)
Backed by data
In preparation for its Surry plant SLRA, Dominion Energy and partners have performed "extensive research" on the reactor vessel, the concrete reactor containment structure, and high-voltage electric cables, deemed the three areas of most importance, Richard Zuercher, Dominion's nuclear communications manager, told Nuclear Energy Insider.
The research concluded that these systems were able to meet their design function for 80 years of operations, he said.
Performance predictions are based on assumptions on the ageing of components, making it crucial to monitor critical equipment closely, Zuercher noted.
Particular emphasis will be placed on monitoring equipment that is not foreseen to last, including machinery such as feedwater heaters and the main electric generator, he said.
Industry-level research has also supported the preparation of SLRA's.
Recent research by the U.S. Department of Energy (DOE) national laboratories, the Electric Power Research Institute (EPRI), and industry groups analysed the impact of extending operations on major metal components in the reactors, including reactor pressure vessels. The DOE and EPRI also investigated the long-term behavior of concrete and containment structures, electrical cables, and instrumentation and control (I&C) systems.
The research concluded “there are no generic technical issues that would prevent a well-maintained nuclear power plant from operating safely during its second licence renewal period,” the NEI said.
"Rigorous inspections, innovative maintenance and repair techniques and continuous upgrades will ensure nuclear power plants continue to operate safely into the future,” the industry group said.
In addition to safety priorities, operators must also use plant monitoring and proactive procurement to reduce maintenance costs and maximize revenues.
Operators are being urged to implement data analytics and predictive maintenance strategies to reduce spare parts costs and minimize downtime.
As Zuercher notes, “it’s more cost effective to plan for the anticipated replacement of equipment, than to run equipment to failure and have to buy it immediately at market prices.”
By Jax Jacobsen