UK needs more nuclear for low-carbon future, says National Grid

14 July 2017

The UK needs to build 14.5 GWe of new nuclear capacity by 2035 or it will fail to meet the Two Degrees scenario, National Grid says in the annual update of its Future Energy Scenarios it published yesterday. The report also suggests that national electricity demand could peak at 85 GWe by 2050, compared with around 60 GWe today. National Grid is the private company which runs Britain's high-voltage electricity network.

Two Degrees is one of four scenarios presented in the report and refers to the aim set by the Paris Climate Change Agreement to keep global temperature increases this century well below 2 degrees Celsius. The agreement was adopted in December 2015 at the 21st conference of the parties (COP21) to the United Nations Framework Convention on Climate Change held in Paris. The agreement, which entered into force on 4 November 2016, also aims to drive efforts to limit temperature increases to below 1.5 degrees Celsius.

As a scenario in the National Grid report, Two Degrees has the "highest level of prosperity". The first new nuclear plant comes on line in 2026, with a total of 14.5 GWe of new nuclear capacity built by 2035.

"Increased investment ensures the delivery of high levels of low-carbon energy. Consumers make conscious choices to be greener and can afford technology to support it. With highly effective policy interventions in place, this is the only scenario where all UK carbon reduction targets are achieved."

In this scenario, there is a "collective ambition to decarbonise the economy", it says. "High taxes are levied on those who continue to use carbon intensive options, such as conventional gas for heating. Policy and incentives are in place to reduce demand and increase renewable generation. This ensures progression towards the long-term green ambition. Society is very conscious of its carbon footprint and is actively trying to reduce carbon emissions. Consumer demand for new green technologies is high and they are happy to spend money on home energy management systems, low-carbon heating and insulation. There is also a drive to make transport greener."

Other scenarios

In the Two Degrees scenario nuclear supplies the largest share of electricity in 2050 - 31%, with offshore wind just behind, while in Steady State it falls to 12%, with gas dominant.

In the Steady State scenario, business as usual prevails and the focus is on ensuring security of supply at a low cost for consumers. "This is the least affluent of the scenarios and the least green. There is little money or appetite for investing in long-term low carbon technologies," the report says.

Under this scenario, only Hinkley Point C is built out of the current set of new build projects, and the closure of existing advanced gas-cooled reactors means that nuclear power's share of the electricity mix drops substantially. However, nuclear has a more favourable outlook in the report's other scenarios.

"In a Consumer Power world, there is high economic growth and more money available to spend. Consumers have little inclination to become environmentally friendly. Their behaviour and appetite for the latest gadgets is what drives innovation and technological advancements. Market-led investments mean spending is focused on sources of smaller generation that produce short- to medium-term financial returns," the report says.

"In Slow Progression, low economic growth and affordability compete with the desire to become greener and decrease carbon emissions. With limited money available, the focus is on cost efficient longer-term environmental policies. Effective policy intervention leads to a mixture of renewable and low-carbon technologies and high levels of distributed generation," it says.

In all four scenarios, the majority of the existing nuclear fleet is decommissioned by 2030, which leads to a dip in nuclear capacity from the early 2020s onwards, due to a gap between old plants decommissioning and new nuclear plants beginning to generate, the report says.

"There are many challenges in building nuclear plants at such pace and scale," the report says. "Financing for these large projects and political support can be assumed in a high prosperity, green world such as Two Degrees. However, issues such as supply chain problems and legal challenges can all derail intended project progress. While this trajectory is plausible, a number of factors need to align for this amount of new nuclear build to progress."

In Slow Progression and Consumer Power, a "smoother build profile" post-2040 can be seen due to the assumption that small modular reactors will have developed sufficiently to begin being built, the report suggests. The size and standardisation of these reactors make them quicker and easier to build than bigger nuclear plants, it adds.


The report refers to technological developments that could make the nuclear fission process "considerably safer and more efficient, as well as reducing the environmental impact". Some of these technologies are already in small-scale use around the world, others are still at the research stage, it notes.

These developments include fast reactors, which "deliver much more energy from the same amount of fuel and can use the waste from older reactors as fuel and produce much shorter-lived waste products", the report notes. Very high temperature reactors are "more efficient, offer additional safety features and allow the direct production of hydrogen instead of electricity", it adds. And thorium reactors "produce less waste and use a more abundant source of fuel".

Research into using fusion to create energy has been in development for a long time, it adds, "due to difficulties in starting and sustaining the required conditions for fusion, and the cost of research".

Researched and written
by World Nuclear News