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The role of nuclear in a green energy transition

In blockbuster films, nuclear energy and technology have created monsters such as Godzilla and Hulk. It usually gains traction in the mainstream media once something has gone wrong - such as the Fukushima Disaster in 2010. However, nuclear may be the key to decarbonising our economies - so, why does it only make up a small fraction of our grids?

The oil shocks in the 1970s led to many countries increasing their. Nuclear efforts - by 1992, the amount of nuclear energy consumed worldwide increased by 130 percent. However, after peaking in 2006, the amount of nuclear energy consumed in 2019 was just 18 percent higher than it had been in 1992 and as a share of global primary energy, it has fallen from 6.1 percent to 4.3.

The role of nuclear energy in the green transition has been peeking around the corner, with the Commission’s Taxonomy confirming its desires to label nuclear as a ‘green investment’ as an attempt to boost funds for the field. What are the pros and cons of nuclear energy? Why is it favoured by some, but scouted by others?

How do nuclear reactors generate power?

Nuclear reactors generate power through nuclear fusion, a process where uranium atoms are split and release energy. In the centre of an atom is its nucleus containing protons and neutrons. During fusion, one of these nuclei breaks apart producing smaller nuclei, some neutrons and energy. If one of the neutrons hits another nucleus, it too will break apart - creating a chain reaction. To ensure this takes place at the right speed and to ensure it doesn’t overheat, control rods are loaded into the reactor. In most reactors, they sit in cooling water acting as a moderator which slows down the neutrons, controlling the rate of the reaction. The energy from the reaction produces heat which is used to turn water into steam in reactors.

The Nuclear Charm?

The efficient shift from fossil-based fuels has put nuclear energy (at times) at the forefront of a very controversial discussion. The shift to renewables, and the fall in the cost of renewable electricity has been central to the decarbonisation of our energy grids. Nevertheless, to achieve an efficient and painless energy transition, we need reliable grinds, which, to date, is not guaranteed by renewables alone. It is argued that despite the dangers and inequities attached to nuclear power (which I will get to in a bit), when well-regulated, nuclear energy is a reliable source of energy as well as a safe one. The graph below by the IEA indicates the cumulative CO2 emissions that were avoided by global nuclear power between 1971 and 2018. Nuclear power has avoided about 55 Gt of CO2 emissions over the past 50 years, nearly equal to 2 years of global energy-related CO2 emissions. However, despite the contribution from nuclear and the rapid growth in renewables, energy-related CO2 emissions hit a record high in 2018 as electricity demand growth outpaced increases in low-carbon power.

France - whose energy grid is 70,6 percent nuclear energy - plans for small, modular reactors (SMRS) that may do better in terms of meeting budgetary needs, as well as being easy to export in comparison to conventional reactors. On the other hand, NuScale - an American company - signed a deal to sell six SMRS to Romania at the COP26.

Unlike renewables, nuclear offers continuous base load supply. This, combined with the established infrastructure in place unlike oil or gas which can be exposed to disruption of supplies, makes nuclear a secure source of energy. In terms of economic arguments, in light of the European ETS system, nuclear power is more competitive than gas or oil in a liberalised market with carbon trading where environmental concerns are reflected in carbon pricing.

Nuclear Energy in the EU

EU Nuclear Generation Capacity

The 103 nuclear power reactors (100 GWe) operating in 13 of the 27 EU member states account for about one-quarter of the electricity generated in the whole of the EU. Over half of the EU’s nuclear electricity is produced in only one country – France. The 56 units operating in three non-EU countries (Russia, Ukraine and Switzerland) account for about 15-20% of the electricity in the rest of Europe.

Legal Framework

Nuclear energy in the EU is governed to a large extent by the Euratom Treaty, which was one of the founding treaties establishing the EU. All EU member states are party to it by default. The European Atomic Energy Community (EURATOM) was established in March 1957 and associated with the Treaties of Rome in 1958 to form a common market for the development of the peaceful uses of atomic energy.

The Treaty set the legal groundwork with the objective of encouraging the growth and development of nuclear technologies while enhancing security of fuel supply for it. Euratom has signed bilateral cooperation agreements to ease trade with its major external partners, and has played a significant role in upgrading nuclear plants in Ukraine. Today, Euratom in its own right is a member of the Generation IV International Forum and the ITER consortium building a fusion reactor. It has remained substantially unchanged and is largely independent of EU parliament's control – a major point of criticism of it.

The Controversies Behind Nuclear

Although nuclear is a proven source of low-carbon, dispatchable electricity giving a high degree of energy security and provides half of the EU’s carbon-free electricity, the sector today faces major challenges within the EU. Historical events globally see people and governments thinking of nuclear with some reservations. After Fukoshima, nuclear power had the lowest support of all energy sources (2011). Further, nuclear power has high capital costs relative to other options, alongside long lead times and operating periods which means that they are a high investment risk to private capital in the absence of guaranteed prices. Further, as nuclear plants rely on imported uranium, the cost of it may rise as demand also rises, which may diminish long-term supply.

It has been feared that countries can use stations as a coverup for developing weaponry. This risks the ‘leak’ of nuclear weapons to countries not recognised as nuclear weapon states under the Non-Proliferation Treaty.

Edit: The biggest factor that I had not put much weight on during my research was the uncertainties that are attached to disposing of nuclear waste. The technology is simply not as developed as it needs to be for nuclear energy to be integrated into our grids just yet. With this uncertainty looming, quoting Denis Florin (Partner at an energy-focused management consultancy) in the Financial Times:

“we cannot go on using nuclear without being adult about the waste, without accepting we need to find a permanent solution.”

It is unclear what we are going to do with thousands of metric tonnes of high-level nuclear waste, some of which can remain radioactive (and lethal) for up to 300,000 years.

What happens if we stop using nuclear power?

In the period running up to 2030, nuclear capacity that will be lost due to the closure of a number of reactors – either because they have reached the end of their operating lifetimes or due to political interference – is expected to outweigh that gained from new reactors. According to Foratom, the early closure of nuclear power would lead to increased CO2 emissions by 2025, which would hamper the increased 2030 mitigation ambitions.

"According to the report, not only would the early closure of nuclear power plants trigger an increase in consumer costs, it will also result in negative environmental impacts," noted Foratom Director General Yves Desbazeille. "These include an increase in CO2 emissions and other air pollutants, higher raw material usage and greater land use impacts."

The closure of plants means the replacement therein with fossil fuel based energy - including natural gas.

Without new policies, natural gas and coal will fill the void. Closing unprofitable and marginal at-risk plants early could result in a 4 to 6 percent increase in US power sector emissions.” (UCS, Nov. 2018)

Bloomberg Green reported that the void left by New York’s Indian Point would mostly be replaced by natural gas and thus,

would be a step backwards for a state moving aggressively toward carbon-free electricity by 2040.

Closing Thoughts

Nuclear power remains a head-scratcher for the public. It is a heated debate within Europe, and the world. Its importance in the energy transition is questionable: while on one hand, the immediate effect of nuclear plant closures means the further reliance on natural gas, the uncertain and yet to be discovered solutions to nuclear waste is troublesome in light of a greener future.


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