UK Electricity Mix
The UK’s electricity generation mix in 2016 was:
- Coal 9%
- Gas 42.2%
- Nuclear 21.1%
- Renewables 24.5%
- Oil and other 3.1%
The electricity generation per region of the UK differs with Scotland producing most of its electricity from renewables (42.9%) and nuclear (42.8%), whereas Wales is predominantly from gas (62.9%), Northern Ireland is still heavily reliant on coal (23.3%) with gas (50%) and renewables (25.3%) forming the other major contributors.
England has a heavy reliance on gas (45%) followed by renewables (23.1%) and nuclear (21.5%).
The UK electricity mix deliberately consists of several sources to ensure that the lights in the UK stay on through a diverse range of sources and technologies that can provide a constant and flexible energy supply.
Shifts in Electricity Generation
Between 2015 and 2016 there was a significant shift in the UK’s electricity generation mix with coal declining by 13.4% and gas increasing by 12.7%. This was partially due to the cost-effectiveness of gas over coal, but it was also due to the requirement to reduce carbon emissions and reduce the UK’s dependency on coal. This resulted from the closure of several coal-fired power stations and the transition of some coal power stations to biomass.
The decline of coal in the energy mix started in 2012 and this continued in 2017 and will continue to fall in the future as other generation capacity replaces the remaining coal-fired power stations.
Renewable electricity generation capacity is growing but its contribution to the UK electricity mix has been stable over the last few years which is largely due to poor weather conditions. Renewable energy technologies include wind, wave, marine, hydro, biomass, and solar.
In 2015, renewable energy production in the UK reached its highest level at 24.6% after several years of marked increases in capacity. Solar and wind capacities account for the largest increase in renewable energy over recent years but historically hydro has been a big contributor in Scotland.
However, renewable energy generation is dependent on the weather and a slight decline in energy was recorded between 2015 and 2016 due to poor weather conditions with a reduction in wind and solar gain. Renewable energy production was also boosted in 2015 by the conversion of the Drax power station from coal to biomass.
Nuclear electricity generation has not significantly altered over recent years despite the closure of the Wylfa power station in Wales which leaves England and Scotland with the only nuclear power stations in the UK.
Importing Electricity
The UK electricity network is also connected to other countries' networks including France, the Netherlands, and Ireland through interconnectors which are cables that run to these countries. These interconnectors allow the UK to import and export electricity to and from these countries. In 2015, 5.8% of the UK’s electricity was imported from France and the Netherlands, and it exported electricity to Ireland.
The UK imports and exports electricity to and from other countries when it is most economical for it to do so and to ensure continuity of electricity supply.
UK Reliance on Fossil Fuels and Carbon Reduction Targets
The UK has been very dependent on fossil fuels such as coal and gas to produce electricity and due to the cost of coal and the increasing pressure to reduce the UK’s carbon emissions the attractiveness of coal has declined. The increase in other forms of electricity generation has replaced the need for coal in the UK’s long-term energy strategy and other lower-carbon alternatives are replacing its capacity.
The UK’s reliance on gas, however, remains as other technologies and fuels are unable to take over the share that gas currently has in the mix. Gas produces lower carbon emissions in its production and burning than coal and therefore has not been targeted as much for carbon reduction.
Gas-fired power stations offer greater flexibility than other alternative generation technologies and therefore remain an essential part of the generation mix. At present gas is also a cheaper fuel than coal so this also works in gas’ favour.
Renewable energy technologies offer the lowest carbon energy solutions that would help the UK meet its carbon reduction targets, but unfortunately, renewable energy generation is not 100% reliable as it is weather-dependent. Therefore, renewable energy cannot increase its share of the UK energy mix too far as it does not offer the flexibility or the stability that the UK needs.
Advancements in energy storage should make renewable energy more feasible in the future but until then the UK will need to continue to operate power stations that can guarantee electricity production.
Nuclear power stations are an alternative option that is a lower carbon producer than fossil fuels. As a result of this, the government has committed to support a new nuclear power station called Hinkley Point C which will increase the UK’s nuclear energy generation capacity and allow the reduction of fossil fuel to continue. However, over the next decade, the UK’s nuclear energy capacity will be declining as the current power stations are scheduled to be decommissioned as they reach the end of their lifespan.
Although nuclear energy is not the most desirable technology for many reasons, it is a low-carbon energy generation technology and therefore it has an important role in reducing the UK’s carbon emissions from energy production.
Background of UK Electricity Generation
UK electricity generation was very much locally focused up until 1947 when the Energy Act resulted in the nationalisation of the UK energy market including generation, distribution, and supply which saw the introduction of the National Grid. In 1990, the UK energy market was privatised which saw the distribution and supply market split into regions and the generation capacity sold off separately.
After the privatisation of the energy market, there was an increase in independent companies that started to make significant contributions to the electricity generation market. It also increased the level of competitiveness in the generation market as the different power stations were purchased by different companies.
In 1992 there was an increase in gas-fired power stations and later the introduction of renewable technologies such as wind turbines started to alter the UK electricity generation mix.
Electricity Market Reform is the biggest change in the UK energy market since the privatisation in 1990. It is a government programme aimed at attracting the investment needed to replace the UK’s ageing energy infrastructure and to decarbonise the UK’s electricity mix. The Electricity Market Reform aims to achieve its ambitions through two schemes:
- Contracts for Difference is a funding mechanism created to support new low-carbon energy generation capacity in the UK.
- Capacity Market is a mechanism for securing the electricity supply in the UK from reliable sources that can deliver energy when needed to provide backup for sources that are more intermittent like renewable energy sources.
Future of UK Electricity Generation
The future of UK electricity generation is heavily dictated by the lifespan of the power stations already established the new generation capacity that is approved and where funding is agreed. The UK power station portfolio has a mixed lifespan and new generation capacity is required to replace those ageing power stations as well as to assist the UK in reducing its carbon emissions by replacing them with more efficient and lower carbon alternatives.
To learn more about the future of nuclear energy in the UK and the rise of low-carbon energy sources, see our article on the future of UK energy.