Nuclear still UK’s main low-carbon power source

Thursday, 26 July 2018

The Digest of UK Energy Statistics (DUKEs), published today by the Department for Business, Energy and Industrial Strategy (BEIS), shows low-carbon sources of electricity accounted for a record 50.1% of power generated in the UK in 2017, which is up from 45.6% the previous year.

This figure consists of 21.0% from nuclear, 14.8% wind (onshore and offshore), 3.4% solar and 2.3% hydro amongst low-carbon power sources.

Tom Greatrex, chief executive of the UK Nuclear Industry Association, said the DUKEs report had “highlighted the continued vital role” nuclear plays as part of the UK low- carbon generation mix, contributing 21% of all electricity, and 41% of overall low carbon power in 2017.

“While the UK has made great progress in meeting its decarbonisation targets, with the anticipated increase in electric vehicles and the electrification of heat, it is important the UK has a secure, reliable, low-carbon solution to meet this increased demand. While the UK benefitted from a particularly windy 2017, the current prolonged period of very low wind output with wind producing just 5.8% of generation over last 28 days demonstrates a balanced mix of power sources is necessary for energy security as well as for meeting our decarbonisation targets,” he said.

“Investment in new nuclear infrastructure is recognised as an integral part of the future mix in the UK government’s nuclear sector deal, particularly as all but one of our current fleet will retire by 2030,” he added.

Nuclear output was down 1.9% - from 71.7 TWh in 2016 to 70.3 TWh in 2017 - which is very similar to the level of generation in 2015. This reduction in nuclear generation was due to a slight increase in outages in 2017 compared to 2016, but primary electricity (nuclear plus wind, solar and hydro) output was up 4.7%.

Primary source

The share of electricity from primary sources (including nuclear, wind, solar and hydro) increased to 41% compared to 37.1% in 2016, while 59% of 2017 generation was from secondary sources (including coal, gas, oil, bioenergy and non-bio waste).

Imports fell by 9.2% whilst exports increased 49.9%, resulting in the 16.8% reduction to net imports. This trend was a result of repairs to the UK-France interconnector in the first quarter of 2017, required after damage by a ship’s anchor in November 2016. Additionally, in the fourth quarter French nuclear outages resulted in increased French electricity prices and increased UK exports. The trend for decreasing utilisation of the French interconnector continued in 2017 falling to 67% from 72% in 2016.

Plant load factors, which measure how intensively each type of plant has been used, with a higher value demonstrating a higher intensity of use, was 46.1% for all plants. Nuclear stations had the highest plant load factor at 77.4%, which was 0.8 percentage points lower than that in 2016 due to more maintenance outages.

Thermal efficiency, which measures the efficiency with which the heat energy in fuel is converted into electrical energy, has for nuclear plants remained between 38% and 40% over the last decade, with it remaining at 40% in 2017. For nuclear stations, thermal efficiency is calculated using the quantity of heat released as a result of fission of the nuclear fuel inside the reactor.

Nuclear power plant capacity was 9.36 GW last year, down from 9.50 GW in 2016 and 9.49 GW in 2015.