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What no one told you about nuclear power

Jenna Careri
By Jenna Careri May 23rd, 2019
5 min read
For business

Editor’s note: Today, Choose Energy reporter Jenna Careri begins a series of articles on nuclear power, where it stands in the U.S. and where it’s going. Up first: What no one told you about nuclear power.

The history of nuclear

A German chemist named Martin Klaproth first identified uranium in 1789. But the concept of nuclear energy didn’t truly take off until the 1930s, when physicist Enrico Fermi succeeded in splitting neutrons into different types of atoms. German and Austrian scientists then confirmed that uranium, when split, releases energy. This is called nuclear fission.

The first nuclear reactor was developed by Fermi and other scientists in 1942 in Chicago. Much of nuclear development from that point on was focused on creating an atomic weapon for use in World War II. The secretive – and ultimately successful – effort was known as the Manhattan Project.

After the war, nuclear science switched gears towards commercial electricity production. Scientists first produced a small amount of electricity at a nuclear reactor site in Idaho. President Eisenhower’s 1953 “Atoms for Peace” program further kickstarted the industry, and the first commercial electricity nuclear reactor was launched in 1957 at the Shippingport Atomic Power Station in Pennsylvania.

How does nuclear power work?

Nuclear power plants are another type of steam-electric power station. Similar to coal and gas-fired plants, steam powers the turbines which generate the electricity. Unlike coal and gas-fired plants, a nuclear reactor uses uranium to create steam. When uranium undergoes nuclear fission, it splits into two lighter atoms and releases the difference in energy as heat. In the reactor that heat is used to boil water.

Uranium nuclear fission is self-sustaining, but the fuel is changed every few years to make the reactor as efficient as possible.

World nuclear power

As of today, 454 nuclear power reactors supply 10 percent of the world’s electricity. The reactors are scattered throughout 31 countries, but 30 percent of all nuclear power is generated in the U.S.

The U.S. is the leader in nuclear power generation, followed by France and China. France is also the country that gets the most of its electricity from nuclear power (71.6 percent). Behind France is Ukraine at 55 percent and Slovakia at 54 percent nuclear-powered electricity.

U.S. nuclear power

The U.S. is home to 98 nuclear reactors in 30 states, which have contributed to about 20 percent of U.S. electricity every year since 1990. Illinois is the most nuclear-heavy state, with 11 reactors spread across 6 plants adding up to 11.9 percent of the country’s total nuclear power generation in January of 2019. Pennsylvania follows with 10.4 percent and then South Carolina with 6.8 percent.

Meanwhile, New Hampshire is the state that gets the most of its monthly electricity from nuclear power. In January 2019, 57.6 percent of New Hampshire’s power came from nuclear, followed by 55.8 percent for South Carolina and 51 percent for nuclear-giant Illinois.

Nuclear Safety

There have been three major accidents in nuclear power’s history. Two had no fatalities.

  • Three Mile Island—March 28, 1979
  • Chernobyl—April 25, 1986
  • Fukushima—March 11, 2011

The Three Mile Island accident was caused by an equipment malfunction that melted part of the reactor core. Panic ensued due to confused media reports but the accident itself did not release any harmful emissions or have any negative health effects on the surrounding population.

The Chernobyl disaster in the Ukraine in the former Soviet Union resulted from a combination of a poor reactor design and lack of nuclear safety protocol due to the Cold War. The Soviet-designed reactor was undergoing routine testing when a power surge ruptured its circuits. An operator had disabled the automatic shutdown system before the tests began, so the reactor continued to run despite building pressure and eventually exploded.

Chernobyl is the only civil nuclear power accident to cause casualties, killing two workers immediately and 28 more within a few weeks from radiation poisoning. It may be a factor in later deaths of 19 other workers, but this can’t be confirmed. Interest in the accident has been renewed because of a new HBO mini series.

The Points Guy visits Chernobyl more than 30 years later: Read what happened

The Fukushima Daiichi accident was caused when a 9.0 magnitude earthquake was followed by a 15-meter tsunami. Only three of Fukushima’s six reactors were in operation and all three shut down automatically in reaction to the earthquake. However, the tsunami disabled the reactors’ cooling mechanisms, melting the cores and allowing radioactive material to leak into the water. The natural disasters caused 19,000 deaths at the time and 1,000 more in the months that followed, but the nuclear area was quickly evacuated and none of those deaths were related to nuclear radiation.

As for environmental risks, the generation of nuclear power produces next to no carbon dioxide emissions. The reactors themselves emit no CO2, and the only carbon dioxide produced comes from the construction of the plants or mining of uranium ore. This adds up to between 10 and 130 grams of carbon dioxide per kilowatt hour. Natural gas, meanwhile, produces 450 grams of CO2 per kWh and coal a whopping 900 g/kWh. Accounting for accidental deaths and deaths from emissions, nuclear is the number one least deadly major energy source.

Nuclear power plants also have the highest capacity and reliability for energy generation, which means one nuclear reactor can produce up to two times the amount of electricity as a coal plants and up to four times that of a renewable plant.

How much nuclear waste is produced? What do we do with it?

Nuclear power produces three categories of radioactive waste. Three percent of the waste produced is considered high-level, or waste that is 95 percent radioactive. Seven percent is intermediate-level waste at four percent radioactivity. The remaining 90 percent is low-level waste that is only one percent radioactive.

The waste loses its radioactivity over time. Highly radioactive waste like used fuel needs to be stored in water or a special dry storage container. All waste can be disposed of underground in stable rock formations. The more radioactive it is, the deeper down it is buried, though the U.S. doesn’t currently have a permanent disposal site. That said, it only takes 30 grams of fuel to generate enough electricity for one person for a whole year.


Next in the series: Nuclear energy’s perception problem, June 6.

Jenna is a writer covering the environment and energy industry. She is a Massachusetts native and graduated from the University of Massachusetts Amherst with a bachelor’s degree in journalism and French.