Department for Energy Security and Net Zero

The department's central question is simple: can Britain power itself reliably, affordably and safely? After decades of energy policy, billions of pounds of investment and countless strategies, the answer remains uncomfortably unclear.

Start with what has worked. Renewables generated 52.5 percent of Britain's electricity in 2025, the second consecutive year above 50 percent. Wind alone accounted for 30 percent. Total renewable capacity reached 60.6 GW in 2024, over 26 times the level installed in 1996. Coal has effectively disappeared from electricity generation. These are real achievements. Britain has decarbonised its grid faster than most comparable economies.

Now look at what has not.

Nuclear output dropped 12 percent in 2025 to 35.9 TWh, roughly half the volume produced in 2015. As old reactors closed, gas generation increased 4.7 percent to 91.6 TWh, claiming a 31.5 percent share of the grid. Britain is adding renewables at speed while losing the baseload capacity that keeps the lights on when the wind drops. Gas is filling the gap. That was not the plan.

Hinkley Point C was supposed to be generating electricity by now. Instead, the project has experienced repeated cost overruns and timeline extensions. Generation is not expected until the late 2020s at the earliest. Sizewell C received its final investment decision in July 2025, with the government committing £14.2 billion and EDF estimating the total capital cost at £38 billion in 2024 prices. Even at that price, EDF claims a 20 percent saving compared with Hinkley Point C. Britain's nuclear ambitions are measured in decades and tens of billions. Its nuclear reality is measured in closures.

Energy bills remain the issue voters feel most directly. Labour promised before the election to cut household energy bills by £300. That promise has not been kept. The CEO of Octopus Energy told the Energy Security and Net Zero Select Committee that electricity bills would be 20 percent higher in four or five years even if wholesale prices halve. The CEO of E.On UK said that even if wholesale prices fall to zero, bills would remain at current levels because of rising non commodity costs: network charges, levies, policy costs and the Sizewell C RAB levy. Total energy subsidies and grid integration costs are forecast to double from £19.8 billion in 2024/25 to £40.1 billion in 2030/31. The government is moving some legacy renewable levies from bills to general taxation to reduce household costs by an average of £150 per year between 2026 and 2029, at a fiscal cost of £2.3 billion. That is a transfer, not a saving. Somebody still pays.

Industrial electricity prices are among the highest in the developed world. Industrial energy consumption fell in 2024 to its lowest level in at least 50 years. The energy industry's contribution to GDP peaked at 10.4 percent in 1982 and has fallen to 2.4 percent. The government is introducing the British Industrial Competitiveness Scheme from 2027 and the British Industry Supercharger for around 550 energy intensive businesses. Those measures acknowledge the problem. They have not yet reversed it.

The grid is the bottleneck nobody planned for. Major grid infrastructure projects needed to connect wind farms have been delayed to at least 2031. NESO estimates that the delay of even a single project could add over £0.5 billion to annual constraint costs, and compounding delays across multiple projects could escalate costs by billions. Offshore wind farms receive planning approval long before the infrastructure needed to deliver their electricity exists. The ambition has been impressive. The wiring has not kept up.

In the North Sea, the government has ceased issuing new exploration licences while introducing Transitional Energy Certificates allowing limited development of existing fields. The Energy Profits Levy remains in place. Offshore Energies UK, which represents operators, claims the policy will "cost tens of thousands of jobs, cripple investment, undermine Scotland and the UK's energy security." Whether that is industry lobbying or accurate projection depends on your perspective. What is measurable is that North Sea production is declining, import dependency is rising and the jobs in Aberdeen and the north east of Scotland are not being replaced at the rate they are disappearing.

The department can legitimately claim success in decarbonising the electricity grid. Fifty two percent renewables is a generation defining achievement. What it cannot yet claim is that the transition has made Britain richer, more competitive or less vulnerable. Energy bills are rising. Industrial consumption is at a 50 year low. Nuclear capacity is halving. Grid projects are late. Subsidies are doubling. The atmosphere is cleaner. The economy is not obviously stronger because of it.

The public will judge energy policy by outcomes. They will ask whether their bills fell, whether British industry strengthened, whether the lights stayed on and whether the country became less dependent on decisions made in Moscow, Doha and Beijing. On those measures, the department has distance still to travel. A country with some of the best wind resources, tidal potential and offshore engineering expertise in the world should not be struggling this hard to keep the energy affordable and the transition on track.