Types of Potential Sites

Coal and nuclear power plants employ broadly similar systems in order to function on the electrical grid. Both use a heat source to generate steam. Then, a steam-cycle system feeds the steam to a turbine that connects to the generator, creating electricity. Finally, a transmission system delivers the electricity to the grid, where it ultimately gets redistributed to consumers.

Among the coal power plants in the United States, there are many different characteristics that may impact the ability to transition making specific coal plants better candidates than others. For more information about the benefits of the transition to nuclear, contact Christine King, GAIN Director, at [email protected] or 650-283-4235.

Types of Potential Nuclear Power Plant Sites

Greenfield Project

With a greenfield project, a new nuclear plant is built on a site that has never been used for industrial purposes, including on a site that previously housed a coal power plant. Learn more >

Reusing Site, Electrical & Buildings

The simplest transition project is one that only reuses the site, electrical equipment (transmission connection, switchyard, etc.), and the civil infrastructure, like road and office buildings, of a retired coal plant. Learn more >

INDirect Coupling to Steam-Cycle Equipment

This transition project is more complex than reusing the site, electrical, and buildings of a retiring coal plant, but is less complex than the direct steam-cycle coupling option. Learn more >

direct Coupling to Steam-Cycle Equipment

The most difficult transition project is one in which a nuclear power plant is directly coupled to the initial coal power plant’s steam-cycle components. Learn more >

Component Compatibility

When considering repurposing components from one technology for another, it is critical to ensure those parts operate as intended. Below we outline key components of coal power plants, their characteristics and compatibility considerations for using them with advanced nuclear technologies.

Compatibility with Site, Electrical and Building Components

At a minimum, potential nuclear power plants can reuse the land within a former coal power plant’s boundaries, its connection to the grid, and its office buildings. Reusing electric components will typically require the total power of a new nuclear plant to be the same or less power than a retiring coal power plant.

Component Questions	Characteristics	Compatibility Considerations
How much electricity does/did the coal power plant generate when operating at full capacity?	10 MW–3,737 MW	The amount of electricity generated by a coal power plant will impact the: – Size advanced nuclear reactor technology that could take its place without upgrading transmission lines. – Amount of waste heat that will need to be managed.
What is the age of the existing coal power plant? What are the environmental conditions of the site?	New to old and already retired	The age of a coal power plant, as well as the site’s conditions, will impact the level of cleanup required prior to connecting a nuclear reactor.

Compatibility with Heat-Sink Components

Any system that generates heat requires cooling that removes excess heat to ensure the cooling of the entire system. A heat sink is anything that absorbs heat.

Both nuclear and coal power plants require some type of ultimate heat sink, typically via access to a cold source of water to dump the excess heat from the power conversion cycle. Its reuse would likely require reapproval and permitting but would provide significant value to an advanced nuclear project. Access to water supply and permits is one of the main benefits of these projects, especially for Western states.

Component Question	Characteristics	Compatibility Considerations
What type of cooling circuit does/did the coal power plant use when operating?	Mechanical draft cooling systems Dry cooling Natural draft cooling tower	The type of cooling circuit used by a coal power plant will impact whether owners of a new nuclear unit: – Can immediately reuse the heat-sink components, OR; – Need to build new heat-sink components, OR; – Need to use air-cooling technology.

Compatibility with Steam-Cycle Components

Reusing some of the coal power plant steam-cycle system components — either directly or indirectly — would provide both the largest challenge and opportunity for reducing the overnight capital cost of a nuclear power plant. The decision to reuse components is technology-specific and site-dependent, coming with both compatibility and licensing challenges.

Component Questions	Characteristics	Compatibility Considerations
What type of steam cycle did/does the coal power plant use when operating?	Subcritical (Sub) Supercritical (SC) Ultra-supercritical (USC)	The type of steam cycle used by a coal power plant could impact if, or which components of, the steam cycle could be reutilized for a nuclear power plant.
How much electricity did each unit generate when operating?	< 1.4 GW	The amount of electricity generated by a coal power plant will impact the: – Size of each new nuclear power generator used. – If turbo-generator components can be used.