US study assesses potential for coal-to-nuclear conversion

A coal-to-nuclear (C2N) transition - siting a nuclear reactor at the site of a recently retired coal power plant - could help increase US nuclear capacity to more than 350 GWe, Investigating Benefits and Challenges of Converting Retiring Coal Plants into Nuclear Plants found. The USA's current nuclear fleet has a combined capacity of 95 GWe.

The report is underpinned by a study carried out by the Argonne, Idaho and Oak Ridge National Laboratories, sponsored by the DOE Office of Nuclear Energy. It is guided by three overarching questions: where in the USA are retired coal facilities located and what factors make a site feasible for transition; what factors of technology, cost, and project timeline drive investor economics over such a decision; and how will C2N impact local communities?

The team screened recently retired and active coal plant sites to identify 157 retired and 237 operating coal plants sites as potential candidates for a C2N transition, which it further evaluated on parameters including population density, distance from seismic fault lines, flooding potential, and nearby wetlands, to determine if they could safely host a nuclear power plant. It found that 80% of the potential sites are suitable for hosting advanced nuclear power plants of varying size and type, depending on the size of the site being converted.

The team then evaluated a case study of detailed impacts and potential outcomes from a C2N transition at a hypothetical site, considering various nuclear technology types for a range of scenarios including large light-water reactors, small modular reactors, sodium-cooled fast reactors and very high temperature reactors.

At the regional level, replacing a large coal plant site with a nuclear power plant of equivalent size could provide some 650 jobs and USD275 million of economic activity, the report found. These jobs are spread across the plant, the supply chain supporting the plant, and the community surrounding the plant and most typically come with wages that are about 25% higher than any other energy technology. Nuclear power plant projects could also benefit from preserving the existing experienced workforce in communities around retiring coal plant sites, which already possess the necessary skills and knowledge that could be tranistioned to work at a nuclear power plant.

Reusing existing coal infrastructure for new advanced nuclear reactors can lead to construction cost savings of 15-35%, the report found. Using existing land, grid connections, office buildings, electrical equipment such as transmission connections and switchyards, and civil infrastructure could also save millions of dollars upfront.

Economic potential exists for owners of coal power plants - and the communities where they are located - from a C2N transition, the report concludes, with a potential further advantage for interested coal communities to be "first movers" in what the authors say could be a series of many C2N transitions across the USA. Although the study's findings inform only at a general level, the results could be used to set up more detailed, in-depth analyses to allow more accurate evaluations specific to a particular coal plant or nuclear technology design.

The report was subjected to independent peer reviews by experts in systems engineering and regional economic modelling to evaluate analysis and assumptions.

The possibility of replacing coal power plants with nuclear capacity is being actively explored in the USA and elsewhere. TerraPower in 2021 announced plans to build a demonstration unit of its Natrium sodium-cooled fast reactor at a retired coal plant site in Wyoming; earlier this year, the the Maryland Energy Administration announced its support for work to evaluate the possibility of repurposing a coal-fired electric generating facility with X-energy’s Xe-100 small modular reactor; and Holtec International recently said it is considering coal plant sites as possible locations for its SMR-160 with plans to bring the first unit online as early as 2029. In Poland, NuScale is exploring with energy company Unimot and copper and silver producer KGHM possibilities for its reactors to replace coal-fired power plants.