A record amount of renewable electricity was wasted across Great Britain and Ireland in 2025 due to grid constraints. More than 12 terawatt hours of clean energy had to be switched off, according to a report from Montel EnAppSys. That amount of electricity would have been enough to power every home in London for a year.
The reason for this waste is because the electricity grid cannot carry all the power being produced. Many wind farms are built in windy areas like Scotland, but the grid there is limited, so only a certain amount of electricity can be sent to homes at one time. When the grid is full, turbines are switched off and clean energy is wasted. This means other, often more expensive, power stations have to be turned on instead, which pushes up energy bills.
The report found that 12.3 terawatt hours of renewable energy was wasted in total, with most of this happening in Great Britain, where 10.2 terawatt hours was lost, a rise of 22% compared to 2024. Almost all of the wasted power in Great Britain came from Scotland, with Northern Scottland alone responsible for 8.8 terawatt hours. That is enough electricity to supply every home in Scotland for a year.
In Ireland, 2.1 terawatt hours of renewable power was wasted, which is equal to the yearly electricity use of homes across County Dublin. Wind power was the most affected. In Northern Ireland, nearly a quarter of all available wind energy could not be used in 2025. The report also found that wasted solar power in the Republic of Ireland was more than four times higher than in 2024, showing new challenges as more solar panels are added.
Fintan Devenney, a senior energy analyst at Montel EnAppSys, said that “only 61% of wind power in Northern Scotland made it onto the grid”. He warned that “while the UK plans to get 95% of its electricity from renewable sources by 2030, better planning of where power is made and used will be needed as demand continues to grow”.
For more information read the full report here!