22 March 2023

Nuclear is one of the greenest energy sources in existence – here’s why

By Tom Greatrex

The UK Government’s decision to classify nuclear investment as sustainable – to ‘green label’ nuclear – is a victory for the facts and a victory for science over ideological prejudice. I think it’s worth reiterating that science.

Nuclear has the lowest lifecycle carbon intensity, the lowest land use, and the lowest impact on ecosystems of any electricity source. We are the only sector that tracks, manages, makes safe, and for new build, pays for, its own waste. If you don’t read any more, that is why nuclear is green.

But if you want to get technical, nuclear is the most ‘energy dense’ source of energy in existence, and therefore has an incredibly low carbon footprint and a minimal impact on the surrounding environment. Or to be clearer still – it is the most powerful and the most efficient source of energy on earth. One kilogram of uranium can release 3m times the energy of a kilogram of coal. One fuel pellet, the size of your fingertip, can produce enough electricity to power an electric car for 20,000 miles. There are 19m of those pellets in the core of Sizewell B. Use up all those pellets, and that car makes the round trip to Pluto (a planet when I was young) 50 times with no emissions. This is the power of E = mc2 played out to save our planet. An incredibly valuable resource when demand for emissions free power is so key to our future.

When it comes to saving our planet, the key to evaluating what technologies are green or not is to conduct comprehensive lifecycle analyses of their impact. From the nuclear sector, that is all we have asked for, to be compared on a like-for-like basis, on a level playing field with all other technologies. That level playing field produces some interesting results:

According to the United Nations Economic Commission for Europe 2022 report Carbon Neutrality in the UNECE Region: Integrated Life-cycle Assessment of Electricity Sources, nuclear has some superb green credentials. It has the lowest lifecycle carbon intensity of any electricity generating technology, at 5.1g-6.4g CO2/kWh, the lowest lifecycle land use of any electricity generating technology and the lowest impact on ecosystems.

That is the science of why nuclear is green. For good measure, nuclear has the lowest lifecycle mineral and metal use of any of the low-carbon technologies. If you’re after specific examples, EDF had lifecycle analyses conducted of Sizewell C and Hinkley Point C. The results? Both projects would have lifecycle emissions of about 5.5g. That would make them the greenest single infrastructure projects in UK history. Even an older station like Torness in Scotland, with lower lifetime output and older construction methods has a lifecycle carbon use of around 10g CO2/kWh of electricity. Good enough to make it one of the greenest energy assets in Scottish history. For comparison purposes, the equivalent figure for offshore wind is 12g and 11g for onshore wind according to the IPCC.

I’ll give you one more example on land. The UK’s existing nuclear fleet, 5,883 MW, produces 15% of the nation’s power from a footprint of just 0.57 square miles. At that rate of 10,295 MW per square mile, we could deliver the 24 GW envisaged in the British Energy Security Strategy in less than three square miles of land. If we want twice or three times that much nuclear, we would still ask for just 10 of the UK’s 94,000 square miles of land. The rest we can leave for natural habitats, for agriculture, or for other development. That is why we have the least impact on ecosystems of any electricity technology.

But what, comes the next question, about the waste? 

Every energy technology produces waste, but nuclear has the most responsible approach to waste management of any energy sector. 

Let’s look at the facts. For a start, nuclear produces a tiny amount of waste for the energy created. More than 95% of the radioactivity in waste is confined to a small volume of High Level Waste (HLW). After 67 years of nuclear power generation (and prior years of research and development), there is a dishwasher tablet’s worth of HLW for everyone in the UK: the packaged volume of HLW is 1,470m3 – a little over two-thirds the volume of one Olympic size swimming pool – for 66 million people. In that time, nuclear has provided over 3000 TWh of electricity, enough to power every home in this country for 28 years.

HLW is not the only kind of waste, but the small volumes compared to other technologies facilitate responsible management. Indeed, the nuclear sector is the only sector that tracks, isolates, manages and makes safe its own waste.

The Nuclear Decommissioning Authority publishes a regular inventory of the UK’s nuclear waste (see 2022 Waste Report), which gives the volumes, sources, future projections and intended final destinations of the different types of waste. You will not find that elsewhere.

Nuclear waste is stored at specialist nuclear facilities and does not leave the care of dedicated nuclear professionals. We recognise the particular nature of our waste and adhere to strict regulatory requirements and the highest standards of monitoring and oversight. Over the years, reactor designs have become much more efficient in terms of waste production and the sector itself has taken a hard look at itself to learn lessons and to constantly adapt and improve our practices.

What is more, we are not still searching for the answers for how to make waste safe. In geological disposal we have an answer: turn it into glass, encase it in concrete casks, bury that concrete deep in the ground, surround it with cement, and seal it up.

When we look to the future, new nuclear projects are the only energy projects that are required to have funding streams set aside for decommissioning and plans for the on-site storage, treatment and final disposal of all waste, before construction can begin. Decommissioning is priced into new nuclear projects. Hinkley Point C, for instance, has a funded decommissioning stream worth £2/MWh, which is incorporated into the overall project strike price. Sizewell C and all future nuclear projects will also have dedicated funding.

Every sector should do it. Only nuclear does.

For those who want to read more (and I encourage you to do so) you can look at the comprehensive technical assessment the EU commissioned from its Joint Research Centre as part of the development of its sustainable investment taxonomy. 

They examined nuclear against six environmental objectives, which are the same ones that the UK will use: Climate change mitigation, climate change adaptation, sustainability and protection of water and marine resources, transition to a circular economy, pollution prevention and control, and protection and restoration of biodiversity. and ecosystems

That report, ‘did not reveal any science-based evidence that nuclear energy does more harm to human health or to the environment than other electricity production technologies already included in the Taxonomy as activities supporting climate change mitigation’.

So when the Chancellor says that ‘subject to consultation, nuclear power will be classed as environmentally sustainable in our green taxonomy’, he is following the science.

The science says nuclear has the lowest carbon, lowest land, lowest ecosystem impact. So we follow the science: nuclear is green.

Click here to subscribe to our daily briefing – the best pieces from CapX and across the web.

CapX depends on the generosity of its readers. If you value what we do, please consider making a donation.

Tom Greatrex is Chief Executive of the Nuclear Industry Association.

Columns are the author's own opinion and do not necessarily reflect the views of CapX.