Spotlight on renewables: How did the UK’s energy mix change in 2020?

EU data released this week revealed that renewable generation overtook coal and gas in 2020. But what happened in the UK's renewable energy markets in 2020, amid the Covid-19 pandemic? Here, we round up the key facts and stats on capacity and output.

Spotlight on renewables: How did the UK’s energy mix change in 2020?

Images (L-R): CORE

A study from think-tanks Ember and Agora Energiewende made headlines earlier this week, with readers celebrating the fact that renewables became Europe’s main source of electricity generation in 2020. The headline finding was that renewables generated 38% of the EU’s electricity last year as the share of fossil fuels in the generation mix fell to 37%. Nuclear power accounted for the bulk of the remaining 25%. Due to Brexit, the study’s figures do not account for the UK.

BEIS has not yet published data for 2020 Q4 but claims that the UK’s total renewable generation capacity grew by 1.2GW between Q3 of 2019 and Q3 of 2020. In terms of generation, renewables accounted for 40.2% of generation between January and the end of September 2020, while the fossil fuel share, buoyed by coal, stood at 42.5%.

It is also worth noting that several coal-free generation records were broken during 2020, leading to the National Grid ESO dubbing the year the “greenest ever”. Coal provided just 1.6% of Britain’s electricity generation in 2020, down from around 25% in 2015. In total, the nation was powered coal-free for more than 5,147 hours during 2020, up from 3,666 hours in 2020. The longest consecutive coal-free streak lasted for two months and fell during the second quarter of 2020.

With all of this in mind, edie has decided to take a closer look at the trends which shaped the nation’s renewable energy sector against a turbulent year of events.


2020 is regarded as the first full calendar year of the UK’s subsidy-free solar era. The Renewables Obligation (RO) scheme closed in 2017 and the phase-out of the Feed-in Tariff scheme (FiT) was completed in 2019.  

According to new analysis of BEIS data by Solar Energy UK and Solar Media Ltd, some 545MW of additional solar photovoltaic (PV) generation capacity came online in 2020 – 27% more than in 2019. This brings the UK’s total installed solar capacity to 13.9GW.

Ground-mounted, utility-scale projects accounted for the majority of the capacity installed in 2020. Despite a slowdown in installations in the first half of the year, the latter half of the year was a busy period. But Solar Energy UK also claims that levels of installation in the residential sphere and the corporate on-site market were strong in 2020.

“The outlook for 2021 and beyond is expected to see continued deployment at the gigawatt-plus level, with investments now flowing into the sector for both rooftop and ground-mount projects,” Solar Energy UK and Solar Media Ltd said in a statement.

Like all renewable generation methods, solar comes with variable outputs. The highest proportion of the UK’s electricity generation mix attributable to solar in 2020 came in May, when figures topped 11%.


Boris Johnson’s government is betting heavily on offshore wind to get the UK to its net-zero target. It wants the UK to host 40GW of generation capacity by 2030 and believes private sector investments of £20bn will be needed this decade to meet the target.  

Offshore wind is, effectively, the only renewable energy sub-sector that was never excluded from the Contracts for Difference (CfD) auction process. The Government U-turned on its previous decision to exclude onshore wind, solar and energy from the CfD – made in 2015 –  in March 2020. This has given offshore wind five years of opportunity to mature domestically. According to Orsted, the cost of electricity from offshore wind fell by two-thirds between 2012 and 2020.

BEIS figures state that the UK played host to 10.5GW of offshore wind capacity as 2020 came to a close. Capacity growth was slower in 2020 than in 2019, as 2019 saw the completion of extensions at the Hornsea One and Beatrice wind farms, bringing their total capacities to 1.21GW and 588MW respectively. Nonetheless, offshore wind accounted for around half of new capacity additions between Q3 2019 and Q3 2020.

BEIS is yet to publish generation figures for the fourth quarter of 2020 or for 2020 as a whole. However, according to the Q3 energy trends report, generation from offshore wind farms was 11% higher year-on-year. The department attributes this to increased capacity rather than majorly different weather patterns.


Of the 1.2GW of capacity added between Q3 of 2019 and Q3 of 2020, just 35MW is attributable to onshore wind. The majority of new additions were located in Scotland, which played host to arrays that generate 80% of the UK’s onshore wind power in 2019.

As well as the Covid-19 pandemic and the historical problems with accessing financing and planning permission hampering developers, operators faced their own challenges in 2020. Lower wind speeds were recorded in almost all regions than in 2020 and some major wind farms dealt with outages.

Renewable UK claims that the UK currently hosts some 13.6GW of onshore wind capacity. It is urging Ministers to develop supporting policies that could help take capacity beyond 30GW by 2030.


Hydro generation capacity did not increase or decrease in the UK between Q3 of 2019 and Q3 of 2020. BEIS believes that the Covid-19 pandemic dampened the investment landscape in this sector to a greater extent than some others.

Outputs from the UK’s hydro arrays, most of which are based in Scotland, were 15% lower on a year-on-year basis in Q3 of 2020. This trend has been attributed to lower average rainfall levels.


Nuclear is, of course, not a renewable power source. But BEIS classes it as low-carbon and produces data on this category, hence its inclusion in this round-up. Moreover, the Climate Change Committee (CCC) has repeatedly maintained that nuclear has a role to play in the UK’s net-zero transition. Its advice on the sixth carbon budget states that nuclear generation capacity will need to maintained at current levels, or expanded.

But 2020 was not a strong year for nuclear in terms of capacity additions or generation.

No new capacity was brought online and talks around the Hinkley Point extension in Somerset stalled, as BEIS staff were scrambled to co-ordinate the economic recovery response. This sparked concerns from trade bodies and businesses, and Johnson was urged to support nuclear through his Ten-Point Plan for the green recovery. The £12bn framework commits £525m to the sector. 

Levels of nuclear generation were the lowest in Q3 than in any quarter since 2008, according to BEIS, with 10.9TWh generated across the three-month period. During this time, maintenance outages started at Hartlepool and Heysham 1, and continued at Dungeness B, Hunterston B, Hinkley Point B and Sizewell B. As a result, nuclear generation accounted for less than 18.6% of England’s mix and less than 24.5% of Scotland’s mix during the quarter.

Sarah George

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