Nuclear Plants

A nuclear power plant is a thermal power generator that produces electricity by splitting atoms to create steam which is then used to power up steam turbines. Statistically, nuclear power plants are extremely safe, but there have been incidences where various malfunctions led to serious problems.

Aaron Baker

May 7, 2021 • Updated Mar 17, 2022 • 6 min read

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In the United States, nuclear power plants produce about 20% of the electricity and over 50% of the carbon-free electricity. Nuclear power plants use sustained nuclear fission to generate heat and electricity. Nuclear fission is the process of splitting or separating one large atom into two or more smaller ones. In the United States, all nuclear power plants use uranium as nuclear fuel. When uranium is split, energy is released in the form of heat which is used to turn a steam turbine to generate electricity.

Today in the United States there are over 50 active nuclear power plants in 28 states. Many power plants have two or three reactors and the average age of reactors in the U.S. is 39 years. Two new reactors at one power plant in Georgia are the only plants to receive construction approval in more than 30 years and are expected to be completed in 2022. However, in the past 30 years, the construction of nearly half of the reactors in the U.S. was completed as they had previous approval. Most scientists predict that nuclear power is declining. By 2050 the percentage of total electricity produced by nuclear power plants is expected to decline as a result of the high cost of reactor construction, decommissioning of older reactors, and competition from gas-fired power plants and renewable energy.

Globally, there have been eight major accidents involving the melting of nuclear fuel (known as a core melt) since 1952. Three of the most notable accidents are Three Mile Island in 1979, Chernobyl in 1986, and Fukushima in 2011. These three accidents combined contaminated large areas and exposed about 39 million people to radioactive material. At least 65 people are thought to have died in the Chernobyl and Fukushima accidents with many more possible as a result of cancer-relatedelated to radiation exposure during these accidents.

The Three Mile Island accident in Pennsylvania was a partial reactor meltdown that resulted in the release of low levels of radiation. Numerous studies on the approximately 2 million residents and surrounding environment determined that the average increase in exposure to radiation was less than 1% of normal background radiation and the effects were negligible.

A sudden surge of power destroyed one of the four reactors at the Chernobyl Plant in the former Soviet Union. The accident and fire that followed released massive amounts of radioactive materials that spread over all of Europe and the rest of the world. Although the government of the former Soviet Union is thought to have suppressed information regarding the human health consequences of the accident, in present-day Russia, Belarus, and Ukraine at least 5 million people were exposed to elevated levels of radiation. The United Nations estimates that about 50 deaths can be attributed to the accident but that another 4,000 might die as a result of radiation exposure. At least 6,000 children developed thyroid cancer mainly from drinking milk contaminated with radiation from the accident leading to 15 deaths by 2005. The former Soviet Union permanently closed off an area within 18 miles of the accident and evacuated over 330,000 people.

In 2011 an earthquake off the coast of Japan caused the Fukushima Dai-ichi power plant to automatically shut down. The plant lost power from the electric grid and began using backup generators. The earthquake produced a 40-foot high tsunami that flooded and damaged many of the generators and backup batteries. Three of the six reactors were operating and the other three were shut down for maintenance. All three of the operating reactors lost power and overheated which resulted in partial meltdowns and explosions that released radioactive material. Over 400,000 people were evacuated including about 160,000 from an area within 12 miles of the accident. Nobody was killed during the accident but there are four cases of radiation-caused illness and one person died of lung cancer in 2018 as a result of radiation exposure during the accident. Approximately 32 million people are thought to have been exposed to elevated levels of radiation. A Stanford University study estimates an additional 130 deaths from cancer could occur.

Your Home and Nuclear Power Plants#

Health and Safety#

Severe nuclear accidents are dangerous and can make areas uninhabitable for anywhere from a few years to many thousands of years. Exposure to high levels of radioactive material can be lethal and exposure to any level above normal background can lead to cancer. A comprehensive statistical analysis published in 2016 estimated that there is a 50% chance of a severe nuclear accident at one of the power plants in the U.S. in the next 25 years and almost a 70% chance worldwide in the next 10 years.

Over 70% of the nuclear power plants in the U.S. have leaked radioactive liquid into the environment. For example, between 2000 and 2009 there were leaks at 38 plants from underground piping. Tritium, a radioactive form of hydrogen, is the most commonly leaked substance. Most leaks were found within plant boundaries but some have contaminated nearby wells and at one site in New Jersey an aquifer that discharges into Barnegat Bay in the Atlantic Ocean was contaminated.All of the known leaks outside of plant boundaries have been at concentrations that do not violate drinking water standards but according to the National Academies of Sciences, any level of exposure to radioactivity will increase the risk of cancer.

In addition, nuclear reactors produce radioactive waste. There is currently no permanent nuclear waste storage site in the U.S. and so each nuclear power plant stores the waste it produces or transports its waste to another active or decommissioned plant for storage. Radioactive waste from nuclear reactors is stored in large pools of water surrounded by concrete and steel for about five years and then is moved into a large dry cask composed of stainless steel and concrete for indefinite storage underground.

Property Values#

Most research, including a study that included all nuclear power plants in the U.S., found that property values decrease within 10 miles of an operating nuclear power plant by as much as 10% but then increase by the same value when a plant closes. The construction, operation, and closing of nuclear power plants are complex operations that involve a large workforce that has the potential to change the housing market adjacent to a nuclear power plant. As a result, even though there is a pattern of property value changes relative to power plants in general, property values around a specific power plant will not necessarily follow the pattern if other variables have a significant impact. For example, a study on two nuclear power plants in California found no negative effects on nearby property values.

What You Can Do#

The US Nuclear Regulatory Commission has emergency planning regulations that require nuclear power plants to establish and follow an emergency plan in the event of a nuclear accident. The plan includes the designation of a 10-mile radius around the plant known as the plume exposure pathway that will be evacuated and a 50-mile radius called the ingestion pathway where all water and food are tested for contamination. Stay safe by following instructions based on the emergency plan from the state or local government regarding evacuation, sheltering in place, or the use of potassium iodide supplements to reduce the absorption of radiation by the thyroid.

If the closing and decommissioning of nuclear power plants can potentially increase property values and reduce safety risks, then determining the age of nearby nuclear power plants may be useful. Nuclear power plants are designed to last between 30-40 years but many have been decommissioned in less time for both mechanical and economic reasons. It is important to note that after a plant is decommissioned, the radioactive waste could be stored at the site indefinitely.

AreaHub’s Knowledge Center is updated regularly and provides information drawing upon scientific studies and sources.