How Nuclear Energy Works

No doubt you’ve heard of nuclear power. But do you know what it actually is, and how it works? More importantly, can you trust that nuclear energy is safe? Here’s all you need to know.

No doubt you’ve heard of nuclear power. But do you know what it actually is, and how it works? More importantly, can you trust that nuclear energy is safe? Here’s all you need to know.

Sofia Hutson
Utilities expert
minute read
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Posted 14 JANUARY 2021

What is nuclear energy?

You’ve heard the phrase splitting the atom, right? It’s likely something you learned at school, referring to the early 20th-century discovery that an atom is not, in fact, the smallest particle in the universe and can be broken down – creating energy in the process.

Nuclear energy comes from splitting atoms inside a reactor. This creates energy, which heats up water, which in turn produces steam. That steam then moves a turbine, generating electricity we can use in our homes.

How does nuclear power work?

Nuclear power generates electricity via a fairly complicated process called the nuclear fuel cycle, which takes places inside a nuclear reactor. In extremely simple terms, uranium atoms are forced to split and release particles in a process known as fission. It’s this fission that creates the heat, which creates the steam, which powers the turbines.

What are the benefits of nuclear power?

Many people don’t like the idea of nuclear power, but it does offer some very clear benefits:

  • Nuclear power has zero emissions
    Nuclear power doesn’t give off harmful CO2. That means it can help the UK lower its carbon emissions.
  • Nuclear power can produce electricity 24/7
    Unlike solar and wind power, nuclear power doesn’t depend on the weather. It’s reliable, meaning that plants can generate electricity around the clock.
  • Nuclear power plants don’t need fuel
    Unlike biomass power plants, nuclear power plants don’t need endless supplies of fuel.
  • Nuclear power produces little waste
    Advocates of nuclear power, such as the World Nuclear Association, claim that nuclear power produces relatively small amounts of waste compared to other forms of energy production. They also say this waste is not especially hazardous and is relatively easy to deal with.

What are the disadvantages of nuclear power?

You’ve probably heard of people protesting against nuclear power. Well, here’s what they don’t like about it:

  • Nuclear power comes with risks
    The Chernobyl disaster, recently dramatised in an award-winning TV series, remains a powerful reminder of how catastrophic it can be if something goes wrong. The Fukushima disaster in 2011 also showed us that nuclear energy has the potential to be very dangerous indeed.
  • Nuclear energy produces radioactive material
    A by-product of nuclear energy is radioactive waste. This is an unstable and potentially extremely dangerous material, which – if not disposed of correctly – is capable of causing cancer, blood disease and bone decay, among other things. And radioactive material lasts a long time – clothes can stay radioactive for thousands of years.
  • Building nuclear power stations is expensive and takes a long time
    Due to incidents like Chernobyl and various other safety concerns, nuclear power has proved a divisive topic over the years. As a result, the planning processes for new plants can typically hit delays, and can sometimes take double the time it takes to build wind or solar farms.
  • Closing down nuclear power stations is difficult, expensive and dangerous
    When nuclear reactors reach the end of their lives, the buildings must be dismantled and decontaminated. As you can probably imagine, this is no easy process. It also involves cleaning up contaminated land.

How safe is nuclear energy?

Nuclear accidents, though not unheard of, are extremely rare. And technology’s adapting all the time to make nuclear power plants safer. The new generation of reactors are designed to make meltdowns a thing of the past.

And while nuclear power isn’t without risk, it’s arguably safer than burning fossil fuels. According to the WHO, air pollution causes some 7 million deaths a year.

What does a nuclear reactor do?

The role of a nuclear reactor is to provide the setting for the nuclear fuel cycle to take place. The reactor is found at the centre of a nuclear power plant and plays host to the process of fission – the chain reaction where atoms split and create the heat that’s used to generate electricity.

How is nuclear energy produced?

The nuclear fission process produces heat, which is then used to boil water and create steam. This steam spins the blades on huge turbines, which creates electricity.

How much does the UK rely on nuclear power?  

The UK currently uses a mixture of energy sources, including nuclear, solar power and gas. We’ve been using nuclear power for some 60 years and look to be showing little sign of stopping. Right now, we have eight nuclear power plants, which supply nearly 20 per cent of our electricity.

A new nuclear power station is currently being built in Somerset. Hinkley Point C is set to start operating in 2025. There are also plans for new nuclear power plants in Suffolk and Essex.

Is nuclear energy renewable?

This is a subject of hot debate. Some people say nuclear power is renewable because it doesn’t emit harmful CO2. Others say it isn’t because the earth only has a finite supply of uranium.

Are there any nuclear power plants near me?

That depends where you live! There are currently two working nuclear power stations in Scotland – one in Torness and another in Hunterston. In England there are nuclear power stations in Hartlepool, Heysham, Sizewell, Dungeness, and Hinkley Point. Wales also has one at its northernmost tip, in Wylfa.