Kitty Dutton, Renewables Consultant at Xodus Group; Member of the 2050 Climate Group Edinburgh

Earlier this week, the Japanese government announced plans to gradually release tons of treated wastewater from the Fukushima Daiichi nuclear power station into the Pacific Ocean. Following the devastating 2011 Tōhoku earthquake and tsunami which tragically claimed the lives of 19,000 people, three of the six nuclear reactors at Fukushima went into meltdown in the most serious nuclear disaster since Chernobyl. For the past ten years, ~170 tons of water a day have been used to cool these reactors, and there are now well over a million tons of contaminated wastewater in storage to deal with. Storage, I hasten to add, which is fast running out of capacity.

I am not a nuclear or a wastewater expert and, while I might feel uncomfortable at the idea of vast amounts of radioactive water being released into the ocean, the Japanese and international authorities are adamant that it will be done safely, and I have to trust that they’re right. But it’s got me thinking about nuclear energy and the extent to which it might be – or should be – deployed as global energy systems transition away from fossil fuels. 

Nuclear energy is often touted as being crucial in decarbonising electricity. While there are emissions associated with construction of power plants and the mining of uranium, the means by which electricity is generated does not produce greenhouse gases. As a result, the lifecycle emissions of a nuclear power station are relatively small, especially when compared to fossil fuels and even in comparison to other renewable sources such as bioenergy and hydropower. Furthermore, unlike renewable energy sources such as wind and solar PV, nuclear power is not dependent on changeable external conditions and can therefore generate electricity at a controllable constant rate, ideal for meeting baseline loads. Global electricity demand is rising as more people gain access and sectors like heat and transport decarbonise through electrification, and proponents of nuclear energy argue that its ability to generate vast quantities of power while requiring relatively little space will be crucial to efficiently meet this growing need.  

These are valid arguments and, given the urgency of the climate crisis, they should not be dismissed lightly. However, there are a number of reasons why large-scale deployment of renewable energy is a preferable approach and why nuclear may actually be more hindrance than help in the energy transition. 

First, renewable energy and nuclear generation thrive under different conditions. Nuclear energy is best suited to systems designed for larger-scale centralised power plants, with finance and regulatory models based around supporting long, costly projects. Renewable energy, on the other hand, is better suited to grids designed to accommodate small-scale, decentralised generation and requires a different nature of finance and regulation. Both would struggle in a system designed for the other. Indeed, as we have seen with renewable energy trying to gain a foothold in systems designed for centralised generation, there can be costly and time-consuming obstacles.   

This means that if countries pursue nuclear to develop decarbonised electricity sectors, they will be doing so to the detriment of renewable energy. For countries that already have well-established grids, new nuclear generation perpetuates the old model of centralised power and disincentivises investment in renewables-friendly infrastructure. And if the country does not already have an established grid, it will mean designing a system around the needs of nuclear further locking in difficulties for renewables.  

Second, renewable energy is much more affordable than nuclear, and prices are steadily falling. Offshore wind in the UK, for instance, achieved strike prices as low as £39.65/MWh at the last Contracts for Difference round, and both onshore wind and solar PV are cheaper still. The new generation of UK nuclear reactors, on the other hand, are estimated to have prices ranging from ~£60/MWh up to £92.50/MWh for Hinkley Point C – a project that is likely to cost at least £22 billion (the world’s largest wind farm cost less than £5 billion), is significantly behind schedule, and is dependent on a technology that has yet to work. While such prices might be affordable to wealthier nations, they could prove prohibitive to many. And were this money spent on renewables and storage instead of on nuclear, it could bring down prices for all further increasing accessibility of clean reliable electricity supply.  

Third, partly because of the prohibitively high upfront costs of developing new nuclear facilities, renewable energy is scalable in a way that nuclear energy is not. Currently only 30 countries – mostly in Europe, North America, and South and East Asia – either have or are constructing nuclear generation facilities, and several of these countries have decided to phase theirs out. It is unlikely that many other countries will be able to join this group. Any new country pursuing nuclear energy will find itself the subject of intense international scrutiny and suspicion as the skills, technology, and resources required for nuclear generation closely align with those required for developing nuclear weapons. Even if a country is a signatory to the Nuclear Non-Proliferation Treaty, the production of weapons grade material produces a global security risk that requires high levels of trust in a country’s internal security mechanisms.  

Finally, renewable energy should be preferred over nuclear precisely because it doesn’t carry the risk of nuclear Armageddon or require the kind of difficult decision making faced by Japan this week. The production of radioactive waste has always been a problem for the nuclear industry, and it remains a problem despite innovations that reduce it. How do you safely store harmful material for tens of thousands of years? Most countries prefer deep geological disposal (i.e. burying it in a very deep hole) but there are difficulties with locating appropriate sites and there is always the worry that it won’t be enough to offer permanent protection. Yet another issue for future generations to deal with.  

This, I think, gets to the root of the problem. Our descendants are already going to have to face the consequences of climate change. We can help minimise this harm by reducing our emissions now and decarbonising electricity, but how we do this will have consequences. We can choose to prioritise a non-renewable technology that perpetuates centralised power grids and crowds out renewable generation, that is expensive, that carries a risk of nuclear weapon proliferation, and that produces dangerous waste. Or we can choose renewable technologies that allow for a greater energy mix tailored to local environments, that are considerably more affordable, that carry no risk of atomic weaponry, and which will not leave future generations yet another mess to clean up. Given the choice, I’d prefer the one that’s less likely to blow up in our face. 

KeyFacts Energy Industry Directory: Xodus Group