Nuclear Power: Energy From Atoms

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How Does Nuclear Energy Work?

Nuclear energy is produced by a process called fission, where large, unstable atoms—like uranium-235—are split apart. When these atoms are hit by neutrons, they break into smaller atoms, release energy in the form of heat, and produce more neutrons.

These new neutrons trigger more fission reactions, creating a controlled chain reaction that generates a massive amount of heat.

That heat is used to boil water, and the resulting steam turns a turbine, which generates electricity.

This process is similar to what happens in a coal or natural gas plant, but instead of burning fuel, nuclear plants rely on the energy inside atomic nuclei.

Inside a Nuclear Power Plant

Most nuclear reactors in the world use light water reactors, which come in two main designs.

1. Pressurized Water Reactors (PWRs)

• Water is kept under pressure so it heats up but doesn’t boil.

• That hot water is sent through tubes inside a steam generator.

• A separate water system surrounds those tubes, turning into steam to spin the turbine.

• The two water systems never mix, which adds a layer of safety.

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2. Boiling Water Reactors (BWRs)

• Water flows through the reactor core and boils inside the reactor vessel.

• The resulting steam goes directly to the turbine.

• This design is simpler, but the steam carries trace amounts of radiation, so shielding is crucial.

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Both reactor types are designed with multiple safety systems to prevent leaks or overheating. Still, accidents at places like Chernobyl (1986), Fukushima (2011), and Three Mile Island (1979) raised serious concerns about what happens when those safety systems fail.

These events showed that even rare accidents can have long-term environmental, health, and political impacts, leading many countries to re-evaluate their energy strategies.

Why Some Support It—and Others Don’t

Nuclear energy continues to divide opinion. Some countries, like France, rely heavily on it and are expanding their programs. Others, like Germany, have begun phasing it out entirely. 

• Why?

Supporters point to the following.

• Low greenhouse gas emissions compared to fossil fuels

• Stable, large-scale power generation that doesn’t depend on weather

• Potential to reduce dependence on coal and gas

While critics argue the following.

• Nuclear waste is dangerous and hard to store safely.

• Power plants are expensive and take years to build.

• Accidents, even rare ones, have massive consequences.

• Public trust and political pressure can limit long-term investment.

Today’s Reality

As of now, nuclear energy provides about 10% of the world’s electricity.

New technologies, such as small modular reactors and next-generation designs, are being developed to be safer, more efficient, and less costly; however, many are still in the testing or early approval stages.

Meanwhile, the world’s demand for energy is growing, and so is the need for energy sources that don’t contribute to climate change. Nuclear energy remains one of the few options that can produce large amounts of electricity without emitting carbon dioxide.

Whether it becomes a bigger part of our future or fades out depends on safety, technology, cost, and public opinion. For now, one thing is clear: understanding how nuclear energy works is essential for making informed decisions about where our power should come from.

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