Fossil Fuels, Renewables And Nuclear: The UK's Changing Energy Mix

To help tackle climate change, the UK has pledged to reach "net zero" - where no further planet-warming greenhouse gases are added to the atmosphere - by 2050.

To achieve this, much less energy needs to be generated by fossil fuels and much more needs to come from renewable sources and low-carbon technologies.

Experts say this would also improve the UK's energy security by reducing demand for oil and gas imports.

Energy is used for various purposes, including heating and powering homes, businesses, transport and industry.

In 2022, the UK imported about 37% of its energy.

That represents a drop from nearly 50% in the early 2010s, but the figure is still higher than in the late 1990s, when the UK was a net exporter - meaning it sent more energy abroad than it imported.

The UK imports proportionally less of its electricity - typically about 5%. In 2022 it was a net electricity exporter for the first time in 44 years, but this was largely because of French nuclear plant maintenance.

In 2022, the majority of the energy used within the UK - 78.4% - came from coal, oil and gas. These are known as fossil fuels.

That is down from 87.2% in 2012, mainly due to the declining use of the dirtiest fossil fuel, coal.

Around one-fifth, or 20.7%, of UK energy use was from "low-carbon" sources in 2022. This is up from 12% in 2012.

"Low-carbon" includes renewables such as wind, solar, hydropower and bioenergy, as well as nuclear.

Nuclear is not considered renewable, but is classed as low-carbon because power stations do not directly release greenhouse gases during their operation.

The output from nuclear energy has actually fallen by around a third in the past decade due to ageing reactors.

Electricity generation accounted for around a third of the UK's total energy use in2022.

Of the electricity generated in the UK in 2022:

By comparison, of electricity generated in 2012:

In particular, power generation from coal has fallen sharply, although natural gas usage remains high.

The use of both wind and solar power has increased rapidly.

In the first three months of 2023, for instance, for the first time wind generated more electricity than gas.

To meet the UK's legally-binding target to be net zero across the economy by 2050, the government has said that all electricity should be generated from "clean" sources by 2035.

Remaining non-electric energy use will have to be net zero by 2050.

Since electricity can be generated by low-carbon sources rather than fossil fuels, demand for it is expected to grow by 40-60% by 2035.

Ensuring electricity is generated as cleanly as possible will therefore be increasingly important to meet the overall net zero goal.

The government has announced various ambitious targets to decarbonise energy and electricity.

These include increasing the capacity of offshore wind, nuclear, carbon capture and hydrogen, all of which are low-carbon technologies.

Recent reports by the government's independent climate advisers the Climate Change Committee (CCC), the National Audit Office and a cross-party group of MPs have all warned that the UK risks missing its 2035 "clean" electricity target without increased effort from Whitehall.

Key recommendations include:

The importance of energy security was highlighted when Russia's invasion of Ukraine disrupted the gas market.

The reduction in Russian supplies increased demand for other countries' gas resources, causing global prices to soar, and pushing up consumer bills.

North Sea oil and gas production has declined greatly in recent years. In an effort to slow that trend, the government has confirmed it will award 100 new licences for oil and gas exploration.

It argues that this will "secure our domestic energy supply and reduce reliance on hostile states".

But a large proportion of reserves in the North Sea supplies have already been used up. In addition, oil and gas from new production licences take on average five years to enter the market, according to the UK's oil and gas body, the North Sea Transition Authority.

Oil and gas prices are set internationally, meaning new production would have little effect on energy prices.

The CCC, along with environmental think tanks Green Alliance and the Energy and Climate Intelligence Unit, argue that the best way to lower bills for customers and boost energy security would be to reduce demand for fossil fuel use by investing in renewable energy projects in the UK.

The government's climate advisers have also warned that the "expansion of fossil fuel production is not in line with net zero".

The International Energy Agency and other bodies say that new oil and gas projects would go against existing international commitments designed to limit global temperature rises to 1.5C. According to the UN's climate body, this is important to avoid the most harmful impacts of climate change.