Britain's Electricity Generation - July 2025
Fuel Type Breakdown
Britain’s electricity generation in July 2025 was led by gas, which accounted for 25% of the energy mix. While this marks a continuation of gas as a primary source, it represents its second-lowest July share in the past five years, signalling gradual progress in reducing reliance on fossil fuels.
Electricity imports contributed 20% of the mix, their highest July share in the past five years. This increase, which placed imports ahead of wind generation, raises concerns about energy security and highlights the importance of bolstering domestic supply.
Wind contributed 19% to the electricity mix, a 2-percentage point decline from July 2024 and 10 points below its July 2023 share, underscoring seasonal variability and the need for continued investment in grid flexibility.
Nuclear provided 15%, down 1 percentage point year-on-year but consistent with its average July performance over the past five years, maintaining its role as a stable baseload low-carbon source.
Solar generation rose by 2 percentage points year-on-year to reach 11%, its highest July contribution in the last five years. Biomass and storage also saw modest increases of 1 percentage point each, reaching 8% and 2%, respectively, both their highest July shares in the past five years.
Hydropower remained stable at 1%, in line with its contribution in July 2024. Coal remained absent from the generation mix, continuing its phase-out completed at the end of 2024.
Zero-Carbon Sources & Carbon Intensity
Zero-carbon sources, including wind, solar, nuclear, and hydro, provided 48% of Britain’s electricity in July 2025. While up from 34% in July 2021, this figure was slightly below July 2023’s 52% and only a marginal improvement over the 47% recorded in July 2024, reflecting limited year-on-year progress.
Carbon intensity rose to 129 gCO₂/kWh, a 13% increase compared to July 2024, driven by lower wind output and increased gas and import use.
Looking at broader trends, the 12-month rolling average for zero-carbon generation held steady at 51%, unchanged from the previous 12-month period. This plateau suggests that the pace of renewable integration has temporarily slowed. The rolling average carbon intensity rose slightly to 131 gCO₂/kWh, up from 129 gCO₂/kWh in June, reinforcing the need for continued decarbonisation efforts.
Despite these short-term challenges, the rolling carbon intensity remains the lowest seen in the past five years, reflecting sustained long-term progress.
Concluding Remarks
July 2025 saw gas return as the leading fuel source, while wind’s contribution fell below recent seasonal norms. Rising imports and a modest increase in carbon intensity signal emerging challenges around energy security and clean generation.
Nevertheless, gains in solar, biomass, and storage demonstrate resilience within the zero-carbon segment. The continued absence of coal and stable nuclear output reinforces the structural transition underway.
To maintain momentum, renewed focus is needed on accelerating renewable deployment, strengthening grid flexibility, and supporting domestic capacity. These are critical steps to ensure consistent progress toward a low-carbon energy future.
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.









