The United Kingdom's increased rollout of solar technology during the last two years has reaped dividends after new figures showed additional capacity and favorable weather had meant that solar power generation so far this year has surpassed that for the whole of 2024.

Since 2023, the Financial Times reports, solar technology capacity has increased by one-fifth, and up until the end of last week, the amount of solar energy produced across the UK in 2025 was already one-third higher than it was at the same time last year.

Research by the University of Sheffield showed that 14.08 terawatt hours of electricity had been produced, which the FT said was sufficient to power 5.2 million homes for a year, or London's Underground rail network for more than a decade.

Josie Murdoch, policy analyst at energy think-tank Ember, said that heatwaves experienced recently by many parts of the country had contributed toward the record productivity.

"Despite the United Kingdom's reputation for gloomy weather, solar has been unstoppable in 2025, thanks to a powerful combination of very sunny weather and record capacity on the system," she said.

In addition to the increased productivity, described by UK's Energy Minister Miatta Fahnbulleh as "a clear sign that our clean power mission is working", the advance in battery storage technology has helped Britain's solar sector.

"There's an enormous number of people wanting to build large-scale solar-plus-battery projects," said Adam Bell, a former head of energy strategy at the Department for Business, Energy and Industrial Strategy, who now works for consultancy group Stonehaven. "Essentially, you produce solar during the day, you store it in the battery and you sell it at the evening peak. There's very little not to like… the future for these projects is enormous.

"As costs continue to decline …it'll just make more sense to install more and more until electricity during the middle of the day becomes essentially free as it already nearly is in Spain."

Despite the increased output and positive momentum, however, the UK still lags behind most of Europe in terms of solar generation, with figures from Ember showing that in July of this year, just 13.44 percent of its energy was solar, compared to Spain's 32.26 percent, or Europe's leader, Luxembourg, with 54.55 percent.

Spain's government is one of the most enthusiastic in Europe when it comes to renewable energy, although it and neighboring Portugal suffered major power supply failures in April, prompting right-wing politician Alberto Nunez Feijoo to say Prime Minister Pedro Sanchez's left-wing government was "so intent on being the greenest in the world that you have led Spaniards into the dark".

In July, the UK's energy regulator Ofgem approved a 24-billion-pound ($32.5-billion) investment program to strengthen energy security and encourage switching to renewable sources.

"Doing nothing is not an option and will cost consumers more — this is critical national infrastructure," said Ofgem CEO Jonathan Brearley. "Britain's reliance on imported gas has left us at the mercy of volatile international gas prices… this record investment will deliver a homegrown energy system that is better for Britain and better for customers."