Recommissioning Nuclear
The recommissioning of nuclear facilities is gaining traction as a solution to meet increasing energy demands. This FAQ provides a high-level overview of the key factors and motivations involved, including the benefits of recommissioning, as well as technical, regulatory, environmental, and future-oriented considerations.
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11 Frequently Asked Questions
The number of nuclear plants that can be restarted is highly limited. Of the approximately 200 power reactors permanently shut down worldwide, only a small fraction are viable candidates for recommissioning. Many decommissioned sites were closed due to reactors reaching the end of their operational life, with regulations requiring the site area turn to greenfield status—meaning all equipment must be removed, buildings demolished, and the land restored to grassy field.
However, some sites were decommissioned for other reasons such as economic barriers, these locations may offer potential for restart if full decontamination and removal of key plant equipment has not started. In the U.S., only three of the 14 reactors shut down in the past 25 years currently have plans for recommissioning.
The process involves assessing whether the plant’s existing condition meets acceptable baselines for structural integrity, cooling capabilities, fire protection, and wastewater management. Ultimately, the feasibility of restarting depends on available infrastructure, community support, state regulatory support and the prioritization of decarbonization within the organization or region.
What is meant by “recommissioning” a nuclear power plant, and what does the process involve?
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What regulatory hurdles and safety upgrades are needed, and how does recommissioning impact nuclear waste management and liability?
What are the financial costs and benefits of recommissioning, and what funding models are supporting these projects?
What are the technical and operational challenges of recommissioning?
How do recommissioned nuclear sites support the energy security, and how does this approach compare to building new nuclear facilities?
What are the environmental risks and benefits, and how does recommissioning influence public perception and community acceptance of nuclear energy?
How does recommissioning align with national and international energy policies, and are similar projects occurring outside the U.S.?
What types of reactors are most suitable for recommissioning projects, and what retrofitting is typically required?
What is EPRI researching on in this field?
What type of organizations or situations make recommissioning a viable solution? How does decarbonization factor in?
What is driving organizations to pursue recommissioning, and what are the associated benefits and risks for both the organizations and the industry?
Recommissioning a nuclear plant requires obtaining a new license, a process that can take two years or more and involves ensuring the facility meets current operational and safety standards. Additionally, training a qualified workforce can take around two years.
There is no precedent for a permanently closed nuclear plant resuming operations, making the potential restarts of Palisades and Three Mile Island a first of kind efforts.
Although the U.S. regulator recognized the potential for a plant to return to operations after starting the decommissioning process (see NRC Reg Guide 1.184), no nuclear power plant licensee has requested reauthorization of power operation before Palisades, Three Mile Island and Duane Arnold. Therefore, this will be a first of a kind regulatory process. Restarting a plant may require significant upgrades, including rewiring, enhanced safety protocols, and expanded waste management systems, such as dry storage that may lead to new regulatory and safety rules.
A viable site requires intact infrastructure and be suitable for modernization. While some plants may undergo only minimal upgrades to resume operations, others may require investments in long-term enhancements, which could enable operation for up to 80 years.
Reactivating a nuclear unit could be significantly more cost-effective than building a new plant, though expenses vary based on the extent of required modernization. Government and private financial incentives can help offset costs and improve viability. Additionally, Power Purchase Agreements (PPAs) could provide long-term revenue stability, reducing financial risk for operators. While recommissioning could remain a more affordable alternative to new construction, its feasibility depends largely on funding sources and supportive policies.
Both Pressurized Water Reactors (PWRs) and Boiling Water Reactors (BWRs) can be recommissioned. However, if key components need to be replaced, the process can become very costly and may involve long lead times. Older designs and obsolete components may necessitate significant modernization, which can drive up costs and make the process financially unviable.
a. life extensions of currently operating reactors; b. power uprates for operating reactors; c. the potential to restart reactors that were abandoned at various stages of construction or those that were built but never operated.
Recommissioning supports both national and global energy policies. While gaining traction in the U.S., existing nuclear assets are being examined to extract more megawatts from them. This has prompted utilities in the U.S. and other countries to consider:
Nuclear plants contribute to the energy transformation by delivering 24/7 carbon-free electricity. They depend on strong community support and a positive public perception for successful execution.
Maximizing the energy obtained from existing infrastructure is key to accelerating the move toward more affordable, reliable and resilient electric power. Recommissioning a nuclear site typically takes 2–5 years and is often more cost effective than building new facilities, offering a practical route to meeting national energy targets. While advanced nuclear technology also holds promise for decarbonization, its widespread deployment remains further in the future.
Growing global support for nuclear power is driven by climate change initiatives, increased load demand due to data centers and the demand for carbon-free electricity, while energy security is driving support of nuclear power in the U.S. The goal with restarting decommissioned plants is to maximize the use of existing infrastructure to produce clean energy as well as potentially acting as a cost-effective alternative to constructing new nuclear facilities.
This approach offers several benefits, including affordable, reliable, and resilient carbon-free energy production, lower investment costs compared to new builds, faster time to production, and the extended lifespan of existing infrastructure.
However, while recommissioning is generally more affordable than new construction, costs can vary based on the extent of required retrofits. Potential risks—such as regulatory challenges, modernization requirements, and market fluctuations—must be thoroughly assessed before proceeding with reopening plans.
EPRI provides technical basis for a plant’s life extension programs and produces guidance documents for safe long-term idling and for safe restarting of units that have been inactive for extended periods.
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