What is nuclear energy and how does it fit into the UK's energy mix?

Did you know that nuclear energy currently makes up around 15% of the UK's electricity generation? This means your cafe, restaurant, barber, or whatever backbone business you run may be, in part, powered by nuclear. 

The amount of nuclear power produced in the UK has been declining since the 1990s, and many nuclear power plants are closed or set to close down by 2030. In most cases, this is because they're coming to the end of their lifecycle or need serious repairs. 

But new stations are being built in the UK, partly funded by the RAB Nuclear Levy. This is to secure future energy generation and help avoid the price shocks we saw in 2022. Nuclear will also contribute to the UK hitting its net zero targets - because nuclear doesn't produce harmful emissions, the UK government is rethinking its use with new energy innovation projects. 

But increasing nuclear power doesn't come without risks. Before we get into that, we’ll walk you through everything you need to know about nuclear energy, its viability as an energy solution and what this means for businesses across the country.

Five-point summary on UK nuclear energy generation

1. Nuclear energy generates low‑carbon electricity using controlled nuclear fission in reactors and currently provides a significant share of the UK’s power mix.
2. Its main advantages are very low direct CO₂ emissions, reliable baseload output and high energy density, which all support net zero and energy security goals.
3. Key disadvantages include high upfront costs, long build times, radioactive waste management and the potential consequences of rare but serious accidents.
4. UK SMEs cannot build their own nuclear plants, but they benefit indirectly through a more stable, lower‑carbon grid and from supply‑chain opportunities as new projects and SMRs roll out.
5. Small businesses should focus on efficiency, on‑site renewables and appropriate tariffs, while nuclear plays its part in the background of the national energy mix.

What is nuclear energy?

Nuclear energy is the energy released from the nucleus (centre) of atoms, the tiny particles that make up every object in the universe. In power stations, this energy creates heat that turns water into steam and spins turbines to generate electricity without burning fossil fuels.

There are two main processes through which we can harness nuclear energy. But nuclear fission is the only one that's relevant when it comes to producing energy for businesses and homes. This is where the nucleus of the atom is split into two or more smaller parts, releasing a lot of energy. This is the process used in nuclear power plants to generate electricity.

One of the greatest perks of harnessing nuclear energy is its ability to produce a large amount of power with a relatively small amount of fuel, and without emitting greenhouse gases during the process. 

Find out more about the different energy types that keep your business running with our guide to decoding the UK energy mix. 

How does nuclear energy generate electricity?

Nuclear fission is the process of generating nuclear power, and here's how it works in simple terms:

• Nuclear energy comes from changes in the nucleus (core) of certain atoms, usually uranium.
• In nuclear power stations, it's released as atoms are split in a process called nuclear fission. This gives off a lot of heat.
• To make electricity, the heat from fission turns water into steam, the steam spins a turbine, and the turbine drives a generator to make electricity.
• It’s 'cleaner' than coal or gas because nuclear plants do not burn fuel in the usual way, so they produce electricity with very low greenhouse gas emissions.

If you want a more detailed explanation, we've also got you covered:

• Fuel — The process begins with a special kind of fuel, usually pellets of uranium-235 or plutonium-239. These materials are chosen because their atoms have large, unstable nuclei on the brink of splitting apart.
• Chain reaction — When a neutron (a subatomic particle) collides with the nucleus of one of these fuel atoms, it triggers the nucleus to split into two smaller nuclei, along with a few neutrons and a high amount of energy. The neutrons that are released can then go on to collide with other fuel atoms, causing them to split and release more neutrons and energy. This creates a self-sustaining chain reaction.
• Heat production — The energy released during the fission process primarily comes out as heat. This heat is used to produce steam from water.
• Electricity generation — The steam produced then drives turbines connected to generators. As the turbines spin, they generate electricity.

Modern reactors use multiple safety systems, control rods and robust containment structures to keep the fission process stable and to reduce the risk of radiation escaping.

The UK’s current fleet is based mainly on large reactors, but the government now plans a “fleet” of small modular reactors (SMRs) that could be built more quickly and at lower unit cost.

What is nuclear energy used for?

You may be surprised to learn that nuclear energy isn’t just used in power plants but can be used across various industries, making it a versatile and robust power source.

Electricity generation

Nuclear power plants are at the heart of electricity generation using nuclear energy. They provide a stable and reliable source of power, capable of producing electricity on a large scale. 

Unlike renewable sources like solar and wind, nuclear power plants can produce electricity continuously, regardless of weather conditions. They play a vital role in ensuring a constant supply of electricity to the grid, contributing significantly to the energy mix in many countries.

In Britain, nuclear provides part of the low‑carbon baseload that complements weather‑dependent renewables like wind and solar, helping to keep the grid stable as more sectors electrify.

The medical field

Nuclear energy is a game-changer in the medical field, especially in oncology. Radiation therapy uses high-energy radiation to shrink tumours and kill cancer cells. Delivering precise doses of radiation targets the affected area, minimising damage to surrounding healthy tissues.

Nuclear energy is also used in techniques like X-rays, CT scans, and PET scans, which rely on radiation to create detailed images of the inside of the body. These images are invaluable for diagnosis, helping doctors see what’s happening inside a patient’s body and plan treatments accordingly.

Industrial applications

Industries use nuclear techniques to test materials for flaws and defects. This non-destructive testing ensures the integrity and safety of structures and components, especially in areas like aerospace, where material failure can have really bad consequences.

Just like in medical imaging, nuclear energy also plays a key role in radiography in industries that use radiation to see inside objects. This is key for inspecting welds, castings, and other parts to ensure they meet safety and quality standards. 

Agriculture

To ensure food safety and extend shelf life, some foods are irradiated — exposed to lower levels of radiation. This process kills bacteria and parasites that can cause foodborne diseases, such as in milk or canned fruit and vegetables. 

According to the Food Standards Agency, in the UK, irradiation can only be used where it's of benefit to the consumer, so a company must show that the benefits of irradiation outweigh any negatives. 

Agriculture also benefits from nuclear techniques in soil analysis and water management. Understanding soil composition and water movement helps optimise crop yields and manage resources efficiently, which is increasingly important in a world facing water scarcity and climate change.

Hydrogen, heat and future applications

New nuclear projects are being explored not just for electricity, but also for providing high‑temperature heat for industry, producing low‑carbon hydrogen and supporting desalination in some countries.

What are the advantages of nuclear energy?

Using nuclear energy can have a wide range of advantages:

Lower greenhouse gas emissions

One of the most significant advantages of nuclear energy is its minimal greenhouse gas emissions during operation. Unlike fossil fuel-based power plants, nuclear reactors do not burn fuel and, therefore, do not emit carbon dioxide (CO2) during electricity generation. This makes nuclear a strong option for reducing overall greenhouse gas emissions and combating climate change.

High energy density

Nuclear energy has an incredibly high energy density compared to fossil fuels. A small amount of nuclear fuel can produce a massive amount of energy. This means that nuclear power plants require less fuel and have a smaller physical footprint to produce the same amount of electricity as fossil fuel plants.

The high energy density also contributes to the cost-efficiency of nuclear energy. Though the upfront costs of building a nuclear power plant are high, the long-term operational costs can be lower due to the efficiency of nuclear fuel.

Nuclear’s high energy density also means less frequent fuel deliveries and smaller fuel storage volumes compared to fossil fuels, which can help with energy security.

Reliable baseload power

Nuclear reactors can operate for long periods at high output, providing “baseload” power that supports grid stability when wind and solar output fluctuates.

Continuous power generation

Nuclear power plants can continuously generate electricity for 18-24 months before shutting down for refuelling, which can take about 10 days. They provide a stable and reliable source of energy, ensuring a consistent electricity supply.

Reduced air pollution

Unlike coal or gas plants, nuclear reactors do not emit air pollutants like sulfur dioxide, nitrogen oxides, or particulate matter during operation. This contributes to cleaner air and better overall air quality, which is crucial for public health.

And this cleaner air can lead to fewer respiratory issues, heart conditions and other health problems associated with air pollution. 

What are the disadvantages of nuclear energy?

While having a range of advantages, like most things, nuclear energy also comes with its disadvantages.

Radioactive waste disposal 

One of the biggest challenges of nuclear energy is dealing with the radioactive waste it produces. This waste remains hazardous for thousands of years and requires secure, long-term storage solutions.

Unfortunately, limited facilities are available worldwide to safely dispose of nuclear waste. Finding suitable locations for waste storage that are geologically stable and away from populated areas is a complex process and one that still needs to be fully ironed out. 

Although the volume of high‑level waste is relatively small, it must be safely managed and stored for very long periods, and older reactors need expensive decommissioning programmes.

Risk of accidents

While nuclear accidents are rare, their potential impact can be severe, as seen in incidents like Chornobyl and Fukushima. Accidents can lead to the release of radioactive materials, causing long-lasting environmental damage and health issues to those in the affected area.

In the event of a nuclear accident, large areas may need to be evacuated, and the land around the nuclear plant could be contaminated for an extended period, displacing communities and affecting local economies.

High initial construction costs

Nuclear power plants are incredibly complex and require a significant investment to build. New nuclear plants can take many years to plan, approve and build, which increases financing costs and makes investment decisions more complex than for smaller energy projects.

The high upfront costs and lengthy construction times can make nuclear projects less attractive compared to other energy sources that can be constructed at half the cost.

The return on investment for a nuclear power plant takes several years, which can be unattractive for investors looking for quicker returns.

What is the cost of disposing of nuclear energy?

The cost of disposing of nuclear waste in the UK is high and depends on various factors, including the type of waste, the disposal method, and the long-term management of disposal sites.

However, according to a report from the National Audit Office (NAO), the cost of decommissioning the UK’s nuclear sites could be up to £260 billion, which is double the current estimate of £56 billion. 

How safe is nuclear energy?

When we think about nuclear energy, safety can often be a touchy subject, but there is no need to worry. Due to the nature of how nuclear energy is handled and how well the industry is regulated, the plants are designed with many safety features, ensuring that everything runs smoothly and securely. 

Regular check-ups and maintenance, like routine plant health checks, ensure they are in top-notch condition. While there have been a few incidents in the past, they have paved the way for learning and improvement, leading to even safer nuclear technology today. 

What are the environmental impacts of nuclear energy?

Nuclear energy is known for its low greenhouse gas emissions during electricity production but has various environmental impacts throughout its lifecycle.

Mining and fueling processing

The mining of uranium — the primary fuel for nuclear reactors — can lead to habitat destruction and soil erosion. It can also contaminate local water sources with radioactive and toxic substances. 

Turning mined uranium into usable fuel involves chemical processes that can produce hazardous waste, so careful management is needed to prevent environmental harm.

Water usage

Nuclear power plants use large quantities of water for cooling. This can impact local rivers, lakes and ecosystems, especially if the water is discharged at elevated temperatures.

Another issue is that some of the water used for cooling is lost to evaporation. This can be a particular concern in regions where water is scarce.

Land use

While nuclear plants have a relatively small physical footprint compared to some renewable energy sources, the need for safety buffer zones means they still require significant land use. 

The need for such land — especially for long-term storage and waste solutions — can have potential impacts on local ecosystems and communities. 

Vulnerability to natural disasters

Rising sea levels and extreme weather events pose risks to coastal and riverside nuclear plants, potentially leading to environmental contamination if a power plant is damaged. 

In earthquake-prone countries, the potential for natural disasters must be carefully considered in the design of nuclear facilities to prevent accidents and environmental harm.

How does nuclear energy affect UK businesses?

Overall, nuclear energy can be a viable option for businesses, offering a low-emission, stable energy source as it makes up some of the nation's existing energy mix.

For UK SMEs, nuclear mainly affects you indirectly through:

1. Grid electricity mix - The share of nuclear in the UK mix influences the carbon intensity of the electricity your business uses, alongside renewables and gas.
2. Tariff options - Some suppliers may offer tariffs that track or support particular low‑carbon sources, so you can choose business electricity that reflects your sustainability priorities.
3. Supply chain opportunities - An expanding nuclear programme, including SMRs and large new plants, also creates opportunities for SMEs in construction, engineering, manufacturing and services.

Is nuclear a viable option for small businesses to install?

In practical terms, UK SMEs cannot build their own nuclear reactors or directly own nuclear plants due to the huge capital cost, safety requirements and strict regulation.

Instead, small businesses can support low‑carbon power by choosing green or low‑carbon tariffs, improving energy efficiency and, where suitable, investing in on‑site renewables or heat pumps.

Nuclear energy, net zero and future UK plans

The UK government plans to increase nuclear capacity significantly by 2050, with ambitions of up to around 24 GW providing roughly a quarter of future electricity.

Projects like Hinkley Point C, Sizewell C and the upcoming SMR fleet at sites such as Wylfa are part of a wider strategy to boost energy security, cut emissions and create clean energy jobs – with many roles in SME supply chains

Get your business set with Bionic

Now that you know all about nuclear power, why not brush up on your knowledge of other energy sources with our energy guides? 

And if you need more help understanding how business energy works, contact the Bionic team. We’re on hand to help with contracts for business electricity, business gas and more.

FAQs on nuclear energy and your small business

Here’s an at-a-glance guide to some of the most frequently asked questions about nuclear energy and UK small businesses:

How much of the UK’s electricity comes from nuclear power?

Recent figures suggest nuclear provides around 10–15% of Britain’s electricity, with plans to expand capacity through new large plants and small modular reactors.

Can a UK small business build its own nuclear reactor?

No, UK SMEs cannot realistically build or operate nuclear reactors because of the huge costs, safety requirements and strict regulations involved.

How does nuclear energy affect my business electricity in the UK?

Nuclear contributes low‑carbon baseload power to the UK grid, which helps reduce the average carbon intensity of the electricity your business buys.

Is nuclear energy renewable or just low‑carbon?

Nuclear is classed as a low‑carbon energy source, not a renewable one, but it still produces far fewer greenhouse gas emissions than fossil fuels during operation.

Will small modular reactors lower energy costs for UK SMEs?

SMRs are designed to be faster and cheaper to build than traditional nuclear plants, but any impact on SME energy prices will depend on future policy, market conditions and project delivery.

Is nuclear power safe for the UK environment and communities?

Modern nuclear plants are tightly regulated and have strong safety systems, but managing radioactive waste, decommissioning and rare accident risks remains a key concern.

How can UK SMEs support low‑carbon power if they cannot use nuclear directly?

SMEs can support decarbonisation by cutting energy use, investing in on‑site renewables and choosing green or low‑carbon business electricity tariffs.

How can Bionic help my UK small business with nuclear and other energy options?

Bionic compares business energy tariffs from a wide range of UK suppliers and can help you find deals that align with your budget and sustainability goals in a changing energy mix.