Britain's Electricity Generation - June 2025
Fuel Type Breakdown
Britain’s electricity generation in June 2025 was led by wind, which contributed 31% of the energy mix, its highest June share in the past five years. This marked a 6-percentage point increase compared to June 2024 and was double the share recorded in June 2021, reinforcing wind’s growing dominance in the summer energy mix.
Gas accounted for just 17% of electricity generation, its lowest June share in the past five years. This represented a 2-percentage point decline from June 2024, and a 50% drop compared to June 2021, highlighting continued progress in reducing reliance on fossil fuels.
Solar generation rose by 2 percentage points year-on-year to reach 12%, its highest June contribution in the last five years. Biomass and storage also saw modest increases of 1 percentage point each compared to June 2024, contributing 8% and 2%, respectively, indicating incremental gains in both dispatchable renewable supply and energy flexibility.
Nuclear contributed 15% to the mix, down 2 percentage points from June 2024 but consistent with its average performance over the past five years, maintaining its role as a stable, low-carbon baseload source.
Hydropower remained steady at 1%, while coal remained absent from the generation mix for the second consecutive June, following its full phase-out.
Electricity imports fell to 15%, a 4-percentage point decline from June 2024. While still notable, this decrease points to an improving balance between domestic generation and external supply.
Zero-Carbon Sources & Carbon Intensity
Zero-carbon sources, including wind, solar, nuclear, and hydro, delivered 61% of Britain’s electricity in June 2025, the highest June share in recent years and an 11-percentage point increase from June 2024. This increase in clean generation contributed to a further decline in carbon intensity, which fell to 98 gCO₂/kWh, 1% lower than the same month last year.
Looking at broader trends, the 12-month rolling average for zero-carbon generation held steady at 51%, consistent with the previous 12-month period. Meanwhile, the rolling average carbon intensity dropped to 129 gCO₂/kWh, its lowest level in the past five years and 4% below the level recorded a year earlier, signaling sustained, long-term progress in grid decarbonisation despite short-term variability.
Concluding Remarks
June 2025 marked a significant step forward in Britain’s clean energy transition, with wind reaching its highest June share in five years and solar achieving a new seasonal peak. These gains, alongside growth in storage and biomass, pushed zero-carbon sources to a five-year high for the month and drove carbon intensity to one of its lowest recorded levels.
The continued decline in gas and the absence of coal underscore the pace of decarbonisation. However, the slight drop in nuclear output, modest hydro performance, and the ongoing reliance on imports highlight areas where further progress is needed to strengthen domestic energy resilience.
Sustained investment in renewable generation, grid flexibility, and energy storage will be key to building on this momentum and ensuring continued reductions in carbon intensity across all seasons.
Britain's Electricity Summary Charts

Monthly Statistics
12-Month Rolling (Average) Statistics
To explore more insights, visit our interactive renewables map
here.
Data source: National Grid ESO 2025
(https://www.nationalgrideso.com/electricity-explained/electricity-and-me/great-britains-monthly-electricity-stats)
About the Author
Doug is a specialist in carbon reporting and research, with extensive experience in supply chain emissions, regulatory compliance, renewable energy developments and sustainability performance improvement. He holds a Master’s degree in Green Economy, which underpins his ability to interpret complex environmental data and advise on practical, impactful strategies.
At edenseven, Doug leads the production of the firm’s monthly Britain’s Electricity Generation report, delivering clear, data-driven insights into the UK’s changing energy landscape. His work supports clients in understanding market trends, emissions performance, and opportunities for cleaner energy adoption.
Doug is a Registered Environmental Practitioner (REnvP) and an IEMA Practitioner, reflecting his professional standing and commitment to advancing sustainable practices across sectors.









