Behind the Grid: Small Modular Nuclear Reactors (SMR)


Nuclear & Small Modular Nuclear

(Published, 01/01/2020, Ruralite)

small modular nuclear reactorMost nuclear power plants use uranium fission to create heat. The heat turns water into steam and the steam then drives turbine generators to make electricity. About 20% of electrical generation in the United States comes from nuclear power. It is the largest contributor of non-greenhouse-gas-emitting electric generation.

Nuclear power is extremely reliable. Often running 24/7 at over 90% capacity for 18-24 months without refueling. It is also scalable, able to meet peak demands for power. Uranium is a fairly common element (about as plentiful as tin) and is found all over the world. However, it requires a great deal of refinement to be turned into a useful fuel.

A Northwest company called NuScale Power is currently working on a technology known as Small Modular Nuclear Reactors (SMRs). These nuclear power plants are designed to be cleaner, safer, and more cost-competitive. Their compact design allows them to be built and assembled in a U.S. factory, then shipped to a prepared site for deployment. SMRs are about one-third the size of traditional reactors and their size and simplicity could reduce the time it takes to construct a new nuclear power plant. These factors make SMRs more flexibile for different scales of production or as demand changes over short periods of time. The U.S. Department of Energy supports the design, certification, and commercialization of small modular reactors (SMRs). The greatest concern over nuclear power regards used fuel. Used fuel (often called ‘spent’ fuel) remains radioactive for many thousands of years and must be contained or else it poses a serious environmental threat. Most nuclear waste in the U.S. is stored in large, water-cooled pools on-site at power plants. A safer but more expensive option for storage are large containers called dry casks. Great strides have been made in reusing old fuel but these methods are not currently considered economical.  Visit the Department of Energy website for more information on nuclear power. 

  • The City of Idaho Falls along with other small utilities in Idaho and Utah support purchasing power from SMRs in the future.
  • The first city in the U.S. to receive electricity from a nuclear power plant was Arco, Idaho in 1955.
  • This rendering (above) is a Small Modular Nuclear Reactor (SMR) which incorporates all of the components for steam generation and heat exchange into a single integrated unit called the NuScale Power Module™ (NPM). Each NPM operates independently within a multi-module configuration. Up to 12 modules can be monitored and operated from a single control. Each module can output 60 Megawatts of electricity, which would power about 30,000 homes.