Historical grid records since 2009.
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Analytics range
Explore the long-term grid transition
Choose a time window to rebuild every chart from the same cleaned 15-minute history table. Power snapshots are converted into energy totals using GW × 0.25 hours, then aggregated into monthly and annual views.
Daily reports
Finalised daily grid summaries
View the latest daily grid summary, including demand, generation mix, carbon intensity and interconnector flows. Reports are updated overnight using the latest confirmed data.
Annual energy
Generation by source
Total domestic generation by fuel, shown in TWh per year. This is the clearest view of the long-term fuel shift.
Executive summary
What changed?
Market share
Generation mix share
Annual percentage share of domestic generation by technology.
Low carbon transition
Renewables vs fossil fuels
Annual wind and solar output compared with fossil generation.
Wind
Wind trend over time
Monthly average wind output in GW, showing seasonal variation and capacity growth.
Solar
Solar trend over time
Monthly average solar output in GW, highlighting the seasonal summer peak.
System demand
Demand and carbon intensity
Monthly demand against carbon intensity to show how cleaner supply affects emissions.
Year-on-year
Latest annual comparison
How the latest available year compares with the previous year.
Cross-border flows
Imports and exports
Total electricity imported and exported each year through interconnectors.
Connected markets
Interconnector imports by country
Annual import energy by connected market. Positive direction is imports into GB.
Records
Historical records
Highest daily average output or peak demand found in the selected range.
Data quality
Coverage and methodology
The page uses the live history table, sampled every 15 minutes. Each power reading is converted into energy before yearly totals are calculated.
Compare years mode
Overlay selected years month-by-month
Compare wind, solar, demand, carbon, imports and exports across the same months in different years. This avoids misleading full-year comparisons when the latest year is still incomplete.
How to read this page
The live dashboard is excellent for a single moment in time. This historical intelligence page is designed for the larger story: how the UK power system has changed across months and years. It converts cleaned generation, demand, carbon and interconnector fields into annual energy totals, monthly trend lines, record tables and year-on-year comparisons.
Wind and solar are shown as long-term trend charts because their value is not just their instantaneous output. Wind can dominate during high-wind winter periods and fall sharply during calm weather. Solar has a very visible seasonal rhythm, rising through spring and summer and falling through autumn and winter.
Interconnectors are treated separately from domestic generation. Imports support GB demand when electricity is available from neighbouring markets, while exports show periods when GB has surplus or competitive generation. Splitting imports and exports year by year makes the direction of cross-border trading clearer than a single live flow number.