Is Nuclear Energy Sustainable?

Below, we briefly discuss whether nuclear energy might be sustainable.

To do this, we assess nuclear energy across various indicators of sustainability.


Firstly, Where Does Nuclear Energy Come From?

The main fuel used for nuclear energy at this point in time is uranium.


Is Uranium A Fossil Fuel?

No, it’s not.

Uranium is considered a nuclear fuel and not a fossil fuel.

There’s several differences between them.

A key difference is that uranium is a radioactive heavy metal, whilst fossil fuels come from fossilised organic matter (which undergoes a formation process over a long period of time)

Another difference is that uranium generates nuclear energy through fission, compared to fossil fuels that generate fossil fuel energy through combustion.

This makes uranium different to the main fossil fuels – coal, natural gas, and oil.


Is Nuclear Energy Renewable?

Nuclear energy is not considered to be a renewable energy source.

Uranium is considered a scarce resource, with only a finite amount left on Earth.


How Much Uranium Is Left On Earth?

Read more about how much uranium might be left in the world in this guide.


Mining Of Uranium

The mining of uranium may have an environmental impact to consider.

It’s worth noting though, if more uranium can be extracted from seawater in the future instead of having to be extracted from the ground, nuclear energy using uranium may become more sustainable at the sourcing/extraction stage.


Greenhouse Emissions From Nuclear Energy

During operation, nuclear power plants don’t emit greenhouse gases such as carbon dioxide.

Nuclear energy might have one of the lowest carbon footprints of all energy sources


Air Pollution From Nuclear Energy

Similar to greenhouse gas emissions, there might be little to no air pollutants released from nuclear reactors.

Nuclear might be one of the cleanest energy sources for the air 


How Much Water Nuclear Energy Uses

Nuclear energy might use a lot of water for cooling the radioactive core of the reactor

Some reports indicate that of all energy sources, nuclear uses either the most water, or the second most water behind coal energy

What’s worth noting is that most of the water might not disappear from the water cycle

Instead, the water might simply be withdrawn for use, and then dumped into the environment once it’s been used

Although, indicates that this water becomes ‘… contaminated with radionuclides’

So, the discharged/dumped water is waste water i.e. it might be low quality water


How Much Land Nuclear Energy Uses

Because nuclear energy has such a high power density, it might use less land than some other energy sources when measuring land use by power density

But, when taking into consideration upstream and downstream land use for mining, infrastructure, and other land uses, nuclear energy’s land footprint might be higher than some other energy sources with less upstream and downstream land use


Energy Efficiency Of Nuclear Energy (Converting Energy To Electricity)

The sustainable use/management of resources is one aspect of sustainability

The efficiency at which different energy sources convert energy to electricity might therefore impact how efficiently resources are utilised

Nuclear energy might be less efficient at converting energy into electricity compared to some renewable energy sources, but more efficient than fossil fuels


How Much Materials Nuclear Energy Uses

Nuclear energy might use less materials for construction compared to renewable energy when considering energy density and power output.


[Regarding renewables,] the dilute nature of water, sunlight, and wind means that at least … 10 – 15 times more concrete, cement, steel, and glass, are required than for nuclear plants (


Waste From Nuclear Energy

Types Of Waste From Nuclear Energy

– Waste water from nuclear reactor

Water is used for cooling, and may be contaminated with radioactive contaminants during use

This water can then be dumped/discharged into the environment


– Spent nuclear fuel

Spent nuclear fuel is essentially radioactive waste


– Construction materials for nuclear reactor

When nuclear reactor reaches the end of it’s lifespan, there’s buiding materials that become waste


How Much Waste Nuclear Energy Generates

– Spent nuclear fuel

A typical nuclear power plant might generate about 20 metric tons of used nuclear fuel per year according to some reports.


– Waste from construction materials for nuclear reactor

One report indicates that nuclear energy might produce less construction waste than solar energy.


… solar panels create 200 – 300 times more hazardous waste than nuclear, with none of it required to be recycled or safely contained outside of the European Union (


So, Is Nuclear Energy Sustainable Overall?

Why Nuclear Might Be Sustainable

On one hand, nuclear energy might be considered more sustainable than other energy sources

A key reason for this might be that there is no greenhouse gas emissions or air pollution whilst nuclear reactors are in operation producing nuclear energy

This factor alone might make nuclear energy more sustainable than fossil fuels across these indicators


Why Nuclear Might NOT Be Considered Sustainable

On the other hand, nuclear energy might not be considered to be sustainable

A key reason for this might be that uranium is a non-renewable resource with finite supplies left

But also, uranium mining may have an environmental footprint, nuclear reactors use a lot of water for cooling that may end up dumped in the environment, and nuclear energy may have some economic challenges in terms of how costly nuclear reactors can be 

Some may also question what we do with nuclear waste long term


How Nuclear Compares To Other Energy Sources For Sustainability

Nuclear energy may be more sustainable than fossil fuel energy sources across indicators like greenhouse gas emissions and air pollutants during operation

Nuclear energy may be less sustainable than renewable energy sources like solar and wind according to the indicator of being renewable vs being non renewable. Renewable energy sources have an almost infinite supply of energy, whereas nuclear has a finite supply of uranium left

Uranium might have a similar sustainability footprint as fossil fuels according to the indicator of the environmental impact of mining/extraction. Both are mined/extracted in similar ways 


Assessing Nuclear Energy Against The General Criteria For Sustainability

There’s a number of ways you could define sustainable.

But, a general definition of sustainable might be:

– The ability to be maintained constantly, especially over the long term

– … without depleting natural resources, degrading the environment, ecosystems or biodiversity


From a resource management perspective, nuclear energy might not be able to be maintained over the long term if uranium resources/reserves become more scarce.

From an economic perspective, nuclear energy might be able to be maintained for countries that can afford capital and operation costs, and for countries that can use it to generate more affordable electricity.

From a practical perspective, in terms of nuclear’s role in a power grid, nuclear energy might be a very useful energy source because of it’s power density, capacity, and reliability.

From an environmental perspective, although uranium mining may degrade the environment in some ways, the generation of nuclear energy at a nuclear reactor doesn’t release greenhouse gases or air pollutants.

So, overall, nuclear energy might be sustainable in some ways, and not sustainable in others.





1. Various ‘Better Meets Reality’ guides





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