New figures have revealed a major challenge facing the UK’s transition to clean energy: huge amounts of renewable electricity are being wasted because the grid cannot move it to where it is needed.
In 2025 alone, wind farms generated so much surplus electricity that 10 terawatt hours (TWh) of clean power had to be switched off. To put that into perspective, analysts say this is enough electricity to power every home in London for an entire year.
For households and businesses already struggling with high energy bills, this raises an important question:
“Why are we paying more for energy when clean electricity is being thrown away?”
What Is Wind Curtailment?
Wind curtailment happens when turbines are ordered to stop generating electricity, even when the wind is blowing, because the electricity network cannot carry that power to homes and businesses.
In 2025:
- 10TWh of wind energy was curtailed across Great Britain
- Billpayers covered £1.4 billion in compensation payments to wind farm operators
- Curtailment volumes rose 22% year on year
Most of this wasted power came from wind farms in northern Scotland, where wind resources are strongest but grid capacity is limited. More than 8.8TWh of clean electricity was switched off there alone – enough to meet all Scottish household electricity demand for a year.
Why Is This Pushing Bills Up?
When wind farms are switched off, the grid still needs electricity. That shortfall is often filled by gas fired power stations and expensive short term wholesale electricity purchases.
At the same time, consumers are paying wind operators not to generate. This double cost is fed directly into higher energy bills.
Energy suppliers have warned that without major upgrades, curtailment costs could add up to £8 billion to UK energy bills by 2030.
Solar Is Now Being Curtailed Too
While wind accounts for the vast majority of wasted renewable energy, solar curtailment is also beginning to rise. In 2025, solar curtailment costs exceeded £250,000 marking a sharp increase from near-zero levels in 2024. As more renewable projects are connected without sufficient grid reinforcement, this problem is expected to grow.
Grid Upgrades Are Coming – But Not Quick Enough
Regulator approval has been given for up to £90 billion of investment in new transmission lines and substations across the UK. However, major upgrades will take a minimum of 5 years to complete, leaving constraint and curtailment payments to continue rising in the meantime. This leaves consumers exposed to higher costs during the transition.
What This Means for Homes in the South East
While grid constraints are often discussed at a national level, the lesson for homeowners is clear, relying solely on the National Grid leaves you vulnerable to inefficiency, waste and price volatility.
In contrast, home solar generation, paired with battery storage, allows households to use the electricity they generate directly on site, reduce reliance on expensive grid electricity at peak periods and avoid paying for wasted energy elsewhere in the system. Unlike large scale wind farms, rooftop solar generates power exactly where it is needed – your home.
Why Solar and Battery Storage Is a Smart Response
At SolarTherm UK we see this trend reinforcing the case for decentralised energy:
- Solar panels generate electricity during daylight hours
- Battery storage captures surplus electricity instead of exporting it to a congested grid
- Stored electricity can be used around the clock, when it is needed most, reducing the need to purchase peak rate grid electricity
This approach maximises self-consumption and protects households from rising grid costs caused by inefficiencies elsewhere in the system.
A Smarter, More Resilient Energy Future
The UK’s renewable rollout is essential, but without grid upgrades, wasted clean energy will continue to drive up energy bills.
For homeowners in the South East, solar PV and battery storage offer a practical, proven way to cut electricity bills, reduce exposure to National Grid failures and take back control of your energy costs.
If you want to understand how solar could work for your property, SolarTherm UK can help. Contact us today for a free, no obligation quote and design, tailored to your property, usage and future energy needs. No hard sell, just honest, expert advice.
Your home. Your energy. Your future.
