Over the last 30 years, almost no new nuclear power plants have been constructed within the U.S. The newest reactor to enter service is Tennessee's Watts Bar Unit 2, which began operation in June 2016. The next-youngest operating reactor is Watts Bar Unit 1, also in Tennessee, which entered service in May 1996.
Recently, the U.S. Nuclear Regulatory Commission (NRC) approved designs by Portland, OR-based NuScale Power for the use of a new type of reactor called a small modular reactor (SMR). SMRs are intended to be built quickly in a factory rather than on site, and have a lower cost, produce much less power, and tend to be safer than traditional nuclear reactors.
NuScale's SMR design is for a 9 feet (2.7 m) diameter by 65 feet (20 m) high reactor vessel, weighing 650 short tons (590 metric tons). The modules can be delivered by rail, barge, or even by truck, and NuScale's SMR will run on 4.95% enriched uranium-235 fuel assemblies that will need to be refueled every two years.
NuScale's SMRs will use conventional light water cooling via natural water circulation that can operate without powered pumps or circulating equipment. However, the SMR will still require a large water reservoir. NuScale's SMRs are intended to be kept in below-ground pools with a concrete lid, in order to absorb the shock of any possible earthquakes. If AC power is lost to the normal cooling systems, the water in the pool is intended to absorb heat and boil. Because of this, the reactor does not need a backup power source, which also helps to keep costs low.
SMRs are intended to meet the need for flexible power generation for a wide range of users and applications. They can replace aging fossil fuel-fired power plants, they require less upfront capital, and they can be used alongside renewable energy sources such as solar and wind. SMRs can also be used for non-electric applications such as desalination.
The NRC's approval means that utility companies can now apply to the NRC to build and operate NuScale's reactors. According to the International Atomic Energy Agency (IAEA), there are currently around 50 SMR designs being developed around the world, and four SMRs are in advanced stages of construction in Argentina, China, and Russia.
How SMRs differ
Traditional nuclear power plants can generate over 1,000 megawatts (MW) of electricity, and 600 MW is enough to power a midsize city. NuScale's current SMR design can generate up to 50 megawatts of power, however, multiple SMRs can be combined to scale up power generation. In 2022, NuScale is expected to apply to the NRC for approval for a newer SMR version that will generate 60 MW of electricity.
NuScale's Vice President of Marketing and Communications, Diane Hughes, recently told Scientific American that between 2023 and 2041, NuScale expects to sell between 674 and 1,682 of its reactors. NuScale has signed memoranda of understanding (MOUs) with the following entities to explore potential projects:
- Ontario Power Generation Inc. (OPG) - Ontario Canada’s public electricity generator
- Bruce Power, L.P. - Canada’s first private nuclear generator
- The Jordan Atomic Energy Commission (JAEC) - to generate power for that country
- Societatea Nationala Nuclearelectrica SA - Romania’s leading nuclear energy provider
- ČEZ Group - a Czech utility conglomerate that owns and operates the Czech Republic’s two nuclear power plants
- Ukraine’s State Scientific and Technical Center for Nuclear and Radiation Safety (SSTC NRS) - to develop power for that country.
NuScale has received vast financial support from the NRC. It received $226 million in 2013 for development, and in 2015, it received $16.7 million to cover the costs of its licensing preparation.
NuScale will build its first nuclear reactor for the Utah Associated Municipal Power Systems (UAMPS). It is a political subdivision of the State of Utah that represents 47 cities or special service districts located all around the Intermountain West. UAMPS members are located in Utah, California, Idaho, Nevada, New Mexico, and Wyoming.
Scheduled to be completed by 2029, the UAMPS reactor will be built on 35 acres at the Idaho National Laboratory, one of the U.S. Department of Energy's labs. Since 1949, various organizations have built over 50 nuclear reactors at the site, including America's first nuclear power plant and the world's first nuclear submarine. The facility has the largest concentration of nuclear reactors in the world.
By 2030, an additional 11 NuScale reactors are scheduled to join the first to ultimately create 720-MW of power generation. While some of that energy will be sold to the U.S. Department of Energy, to date, only 30% of that power has been subscribed.
A fly in the ointment
While proponents of nuclear power point to SMRs' ability to create electricity without adding to global warming, questions remain about how to safely dispose of nuclear waste. Also, the cost is an issue.
In a September 19, 2020 article in Utah's Deseret News, lawmakers in Utah have begun raising questions about NuScale's costs. Two Utah cities, Lehi and Logan, have declined to be part of the project, citing costs. Other UAMPS members have until September 30th to leave the project.
Managers for several power providers have weighed in on the NuScale plant. In the Deseret News article, Jack Taylor, manager of California's Santa Clara City Power, cited the rise of natural gas prices that occurred 20 years ago as a reason to go forward with the NuScale plant. Today, power providers pay around $2.25 per 1,000 cubic feet of natural gas, while in 2000, they were paying almost $14.
The manager of Utah's Brigham City Power, Dave Burnett, defended the need for the NuScale plant by citing California’s recent rolling blackouts and electricity price spikes of more than $1,000 per megawatt-hour.
Regardless of how you feel about nuclear power, it's clear that the world's need for electricity is only going to go up, and SMRs might just be the answer.