UK Carbon Intensity
Loading... 130,089 readings gCO₂/kWh
Low CO₂
High CO₂

Current readings

Most recent half-hour · loading...

All regions · click row to open region detail · click header to sort
Region Now 7d avg 30d avg All-time vs avg Since 2018 Fuel mix now Status
GB generation mix right now estimated · hover segments
Clean vs fossil
Best windows today · next 24 hours · coloured by cleanliness vs historical average
Carbon cost calculator · compare regions · live intensity
Scenario Intensity now Best window CO₂ now CO₂ best window Saving vs best
Live intensity from NESO API. Best window from 48h forecast. GB = national average.
Scheduling score by region · how clean is right now vs historical average for this hour
Score = percentile rank vs all historical readings for this hour of day and month. 100 = cleanest on record. Based on 7+ years of half-hourly data.

Scheduling windows

Where and when to run deferrable workloads · all regions · next 48 hours

Indicative · based on NESO historical patterns
All-region scheduling table · sorted by best forecast window · next 48h
Region Now
gCO₂/kWh		 Best window
gCO₂/kWh		 Peak
gCO₂/kWh		 Spread
gCO₂/kWh		 CO₂ at best
for workload		 Saving vs worst
kg CO₂
Region detail — Yorkshire
Intensity forecast — next 48h
Estimated generation mix

Heatmap

Green = lower carbon · red = higher · hover any cell for exact value

Low
High Hover any cell for exact value

Trend & analysis

Select a view · select regions · toggle intensity or generation mix

Coal exit
The last UK coal power station closed in September 2024. At the start of this dataset coal still supplied around 5% of GB electricity.
Wind growth
Offshore wind capacity more than doubled since 2018. Scotland regularly exports surplus clean power south, often running near zero intensity.
Regional gap
South Wales and the East Midlands remain structurally high-intensity. Transmission constraints prevent clean Scottish power from always reaching English regions.

Regional map

Live carbon intensity by region · hover for detail · click to open region view

gCO₂/kWh now

All regions · now · gCO₂/kWh

Intensity scale
<75
75–150
150–225
225–300
>300
Click a region to open full detail. Double-click to jump to Region tab.
Find your region Enter the first half of your postcode

About

What is carbon intensity?

Carbon intensity measures how much CO₂ is released per unit of electricity consumed — in grams per kilowatt-hour (gCO₂/kWh). The lower the number, the cleaner the electricity.

  • Nuclear, wind, solarUnder 20 gCO₂/kWh
  • Gas (combined cycle)350–400 gCO₂/kWh
  • UK grid average todayAround 150 gCO₂/kWh, down from ~280 in 2018

Why does it vary by region?

The GB grid has 14 regional zones, each with a different generation mix and demand profile. Scotland connects to large wind farms and exports surplus clean power south. The Midlands and Wales have historically hosted more gas plant.

Transmission constraints mean clean Scottish power cannot always reach England, so regions sometimes run on dirtier local generation even when Scotland is in surplus.

How to use this

  • Compute schedulingShift AI training, batch jobs or pipelines to low-intensity windows — typically overnight or midday
  • EV fleet chargingAvoid 17:00–20:00 in most English regions. Overnight is almost always better.
  • Carbon reportingUse location- and time-specific intensity for accurate Scope 2 emissions (DESNZ methodology)
  • Site selectionA data centre in Scotland runs on a fraction of the grid carbon of one in the East Midlands

Data & methodology

Intensity data from the National Grid ESO Carbon Intensity API. 130,089 half-hourly readings across 14 GB regions, Sep 2018 – Mar 2026.

Generation mix data is modelled by NESO using power flow analysis — it is an estimate of fuel consumption per region, not a direct metered measurement. Treat as indicative for operational decisions.

Forecast data uses NESO's ML-based 96h ahead model scaled to current conditions. Built by Posetiv Cloud.

github.com/posetiv/uk-grid-carbon

Region
—
gCO₂/kWh now
Current fuel mix
Monthly intensity vs GB average
Average intensity by hour of day · all-time average
48-hour forecast
Estimated generation mix over time
Hour × month · vs GB scale
Low
High vs national scale
Region at a glance

Power mix

What the GB grid is actually running on · and why it matters for carbon intensity

Current fuel mix by region · sorted by clean energy share · click a region to open detail
GB generation mix 2018–2026 monthly · stacked area
What has changed
Wind share vs carbon intensity monthly GB averages · each point = one month
Gas dependency over time GB gas share monthly
Value
Period