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Protecting persons,
property and the environment

Nuclear Power Plants

About Nuclear Power Plants

Nuclear power comes from the energy that is released in the process of nuclear fission. Most nuclear power plants use enriched uranium as their fuel to produce electricity. This fuel contains greater amounts of a certain kind (or isotope) of uranium known as U-235. Its atoms are more easily split apart in nuclear reactors.

In fission, the nuclear fuel is placed in a nuclear reactor core and the atoms making up the fuel are broken into pieces, releasing energy. The neutrons that are released by one atomic fission go on to fission other nuclei, triggering a chain reaction that produces heat, radiation, and radioactive waste products. If uncontrolled, that chain reaction could produce so much heat that the nuclear reactor core itself could actually melt and release dangerous radiation. That’s why power plants use “control rods” that absorb some of the released neutrons, preventing them from causing further fissions.

The energy released from the fission of uranium atoms heats water, which produces steam. That’s how we get electricity. The steam goes on to spin turbines, which then drive generators.

Do nuclear plants produce greenhouse gases?

No greenhouse gases are emitted by nuclear power plants. Nuclear power also does not create particulate pollution.

Can a nuclear power plant explode like a nuclear weapon?

It is impossible for a reactor to explode like a nuclear weapon. Nuclear weapons contain very special materials in unique arrangements, which is not the case in nuclear reactors. Explosions that occurred at Fukushima were driven by a build-up of high-pressure gases (hydrogen and steam). The resulting explosion is similar to a can of soda exploding upon impact.

Is it easy for terrorists to steal nuclear fuel from nuclear plants and make bombs?

Plutonium is present only in spent (used) fuel, and the high radiation levels of spent fuel, plus the very strong and thick steel and concrete structures where spent fuel is stored, make spent fuel very unsuitable for making bombs. This also makes it very secure against theft for making dirty bombs. Fresh (unused) fuel contains only non-weapons grade uranium, which is sealed inside fuel bundles that weigh roughly 1,000 pounds and are about 12 feet tall. Nuclear bombs need over 90% U235, whereas commercial nuclear fuel is no more than 5% U235. Finally, nuclear power plants have elaborate security, including sensors, barriers and armed guards, to provide added assurance that both fresh fuel and spent fuel remain secure.

How is nuclear energy produced in a nuclear power plant?

Nuclear power plants split uranium atoms inside a reactor in a process called fission. At a nuclear energy facility, the heat from fission is used to produce steam, which turns a turbine to generate electricity. At this point a nuclear plant is similar to a coal, gas or solar thermal plant; those energy sources also generate steam through heat to spin a turbine. The main differences are how the heat is generated and the amount of fuel consumed – in a nuclear power plant, the amount of fuel consumed is tiny compared to that of a fossil fuel plant.

What is the difference between natural radiation and radiation from nuclear energy?

Radiation is naturally present everywhere people live. It comes from a variety of sources, including cosmic rays, solar radiation, and terrestrial radiation from the ground. The background radiation a person receives varies with activities (increases by eating certain foods, drinking ground water, flying on a plane, getting an x-ray) and location (increases by living at higher elevations or in a brick house). Humans evolved in an environment of ever-present natural background radiation, and the radiation from a nuclear plant is the same type as natural radiation, except it is far below background levels and thus poses no threat.

What kind and how much radiation is produced by a nuclear power plant?

An operating nuclear power plant produces very small amounts of radioactive gases and liquids, as well as small amounts of direct radiation.

What happens to radiation produced by a nuclear power plant?

Nuclear power plants sometimes release radioactive gases and liquids into the environment under controlled, monitored conditions to ensure that they pose no danger to the public or the environment. These releases dissipate into the atmosphere or a large water source and, therefore, are diluted to the point where it becomes difficult to measure any radioactivity. By contrast, most of an operating nuclear power plant’s direct radiation is blocked by the plant’s steel and concrete structures. The remainder dissipates in an area of controlled, uninhabited space around the plant, ensuring that it does not affect any member of the public.

Are nuclear plant workers radioactive themselves?

Nuclear plant workers are no more radioactive than anyone else. Except in unusual circumstances, such as an accident at the plant, workers receive only minimal does of radiation and rarely become contaminated with radiation. It is important to remember that being exposed to radiation does not make one radioactive, except in very specific circumstances.

Is radiation exposure from a nuclear power plant always fatal?

No. Routine emissions during normal operation of a nuclear power plant are never lethal. Even in the very unlikely event of a nuclear power plant accident, it would be extremely unlikely that someone would be in an area for a sufficient period of time to receive a radiation dose that would be considered lethal.

What barriers provide protection from radiation produced by a nuclear power plant?

The radioactive material that fuels a nuclear power plant is contained in ceramic fuel pellets that are capable of withstanding thousands of degrees of heat. These fuel pellets are then encased in hollow metal rods that help keep the material from interacting with the water that cools the reactor. In addition, the reactor’s thick metal walls and piping, as well as a massive reinforced concrete containment structure, are designed to keep the coolant, fuel, and associated radiation isolated from the environment.

Why can't a nuclear gauge explode like a bomb?

A gauge does not have enough radioactive material — or the right kind of material — to cause an explosion. It does not have the capability to produce a burst of energy that one would associate with a bomb. Even a nuclear reactor does not explode. The material in a reactor is distributed in such a way that it does not release energy instantaneously; rather, it is a controlled reaction that sustains energy production for beneficial purposes.

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