Earth Notes: GB Grid Intensity YELLOW

 
Grid is OK; but you could still avoid CO2 emissions by postponing running big appliances such as dishwashers or washing machines
 

(Over a longer period, the current status is GREEN.)

You might have saved as much as 70% carbon emissions by choosing the best time to run your washing and other major loads.

Latest data is from Fri Apr 12 16:55:00 UTC 2024. This page should be updated every few minutes: use your browser's refresh/reload button if you need to check again.

Follow this grid status on Mastodon @EarthOrgUK@mastodon.energy.

This free service is in BETA and may be unavailable or withdrawn at any time and is provided "as-is" with no warranties of any kind.

This page shows the current "carbon intensity" of the GB National Grid (ie the England/Scotland/Wales portions of the UK electricity grid) as a simple traffic-light indicator. Carbon intensity is a measure of how much greenhouse gas (especially CO2 or carbon dioxide) is emitted to generate a fixed amount of electricity.

Anything other than a GREEN light suggests that you should consider deferring heavy loads (eg starting a dishwasher or washing-machine at home) because the carbon intensity is relatively high, or because of other factors. Avoiding running major appliances such as washing/heating/cooking during RED times will save CO2 emissions.

You should still conserve first: don't run things that don't need to be run at all, don't leave things on that can be turned off at the wall, run full loads in your washing machine and dishwasher, etc, etc, before worrying about carbon intensity.

Planning ahead: note that in the UK/GB peak demand for electricity will usually be 4pm to 9pm especially on week days in winter (and a lesser peak around 9am/10am), and peak carbon intensity is often around peak demand, so try to avoid big loads then; if possible run loads such as your dishwasher and washing machine overnight, eg on a delay timer or just as you go to bed, or when you have local microgeneration that can cover much/all of the load.

There are various arguments about whether this marginal cost calculation reflects reality, ie in practice is there simply a gas turbine somewhere that gets spun up a little if you demand extra power. There is much less argument about the value of lowering demand generally, and about lowering peak demand on various parts of the infrastructure.

Shifting loads to the night when energy is going into grid-scale storage such as pumped hydro, avoids pulling it out when you would otherwise run/dispatch the load, and thus saves round-trip losses of ~25% for that load.

Technical Stuff

You don't need to understand the numbers below, but some people like to see them!

Effective grid carbon intensity for a domestic user is currently 62gCO2/kWh including transmission and distribution losses of 7%.

Latest available grid generation carbon intensity (ignoring transmission/distribution losses) is approximately 58gCO2/kWh at Fri Apr 12 16:55:00 UTC 2024 over 29142MW of generation, with a rolling average over 24h of 69gCO2/kWh.

Minimum grid generation carbon intensity (ignoring transmission/distribution losses) was approximately 40gCO2/kWh at Fri Apr 12 14:05:00 UTC 2024.

Maximum grid generation carbon intensity (ignoring transmission/distribution losses) was approximately 132gCO2/kWh at Thu Apr 11 18:10:00 UTC 2024.

Average/mean grid generation carbon intensity (ignoring transmission/distribution losses) was approximately 69gCO2/kWh over the sample data set, with an effective end-user intensity including transmission and distribution losses of 74gCO2/kWh.

Recent mean GMT hourly generation intensity gCO2/kWh (average=69); *now (=58)
181920212223000102030405060708091011121314151617*
  • 128
  • 115
  • 86
  • 72
  • 63
  • 55
  • 56
  • 59
  • 56
  • 57
  • 59
  • 78
  • 75
  • 71
  • 80
  • 70
  • 62
  • 57
  • 53
  • 50
  • 42
  • 44
  • 53
  • 126
Mean GMT hourly generation GW (all, zero-carbon)
  • 34
  • 17
  • 33
  • 18
  • 31
  • 18
  • 29
  • 18
  • 26
  • 19
  • 25
  • 19
  • 24
  • 19
  • 24
  • 18
  • 24
  • 19
  • 24
  • 19
  • 24
  • 19
  • 26
  • 18
  • 28
  • 18
  • 29
  • 18
  • 29
  • 18
  • 28
  • 18
  • 27
  • 18
  • 26
  • 18
  • 26
  • 18
  • 25
  • 19
  • 25
  • 19
  • 27
  • 19
  • 29
  • 19
  • 33
  • 16

Hours that are basically green, but in which there is draw-down from grid-connected storage with its attendant energy losses and also suggesting that little or no excess non-dispatchable generation is available, ie that are marginally green, are shaded olive.

Current/latest fuel mix at Fri Apr 12 16:55:00 UTC 2024: BIOMASS@3161MW CCGT@2285MW COAL@0MW INTELEC@997MW INTEW@0MW INTFR@1005MW INTIFA2@992MW INTIRL@0MW INTNED@0MW INTNEM@0MW INTNSL@664MW INTVKL@0MW NPSHYD@533MW NUCLEAR@5375MW OCGT@0MW OIL@0MW OTHER@597MW PS@485MW WIND@13048MW.

Current draw-down from storage is 485MW.

Generation by fuel category (may overlap):

fossil @ 8%
2285MW [CCGT, COAL, OCGT, OIL]
import @ 13%
3658MW [INTELEC, INTEW, INTFR, INTIFA2, INTIRL, INTNED, INTNEM, INTNSL, INTVKL]
low-carbon @ 65%
18956MW [NPSHYD, NUCLEAR, WIND]
nuclear @ 29%
8369MW [INTELEC, INTFR, INTIFA2, NUCLEAR]
renewable @ 57%
16742MW [BIOMASS, NPSHYD, WIND]
storage @ 2%
485MW [PS]

Overall generation intensity (kgCO2/kWh) computed using the following fuel year-2024 intensities (other fuels/sources are ignored): BIOMASS=0.12 CCGT=0.394 COAL=0.937 INTELEC=0.062 INTEW=0.288 INTFR=0.062 INTIFA2=0.062 INTIRL=0.288 INTNED=0.262 INTNEM=0.123 INTNSL=0.012 INTVKL=0.126 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.651 OIL=0.935 OTHER=0.3 WIND=0.0.

Rolling correlation of fuel use against grid intensity (-ve implies that this fuel reduces grid intensity for non-callable sources): BIOMASS=0.6118 CCGT=0.9552 COAL=0.7469 INTELEC=0.4010 INTFR=0.3706 INTIFA2=0.3637 INTNED=-0.2114 INTNEM=-0.1755 INTNSL=0.7855 NPSHYD=0.5046 NUCLEAR=-0.7762 OCGT=0.4783 OTHER=0.4757 WIND=-0.8128.

Key to fuel codes:

CCGT
Combined-Cycle Gas Turbine
INTELEC
INTELEC (France) Interconnector
INTEW
East-West (Ireland) Interconnector
INTFR
IFA1 (France) Interconnector
INTIFA2
IFA2 (France) Interconnector
INTIRL
Irish (Moyle) Interconnector
INTNED
Netherlands Interconnector
INTNEM
Nemo (Belgium) Interconnector
INTNSL
North Sea Link (Norway) Interconnector
INTVKL
Viking Link (Denmark) Interconnector
NPSHYD
Non-Pumped-Storage Hydro
OCGT
Open-Cycle Gas Turbine
OTHER
Other
PS
Pumped Storage Hydro

(Histogram input windows: 24h, 168h.)

Methodology

This estimates the carbon intensity of generation connected to the National Grid GB (Great Britain) high-voltage transmission system, ignoring (pumped) storage and exports but including imports via interconnectors. This excludes 'embedded' generation, eg connected directly to the distribution system, such as small diesels, domestic microgeneration and a significant chunk of wind power, all of which also benefits from reduced transmission/distribution losses, so actual intensity may be somewhat different to (and probably lower than) that reported. However the emissions cost of each marginal/conserved kWh is probably accurately reflected.

(Colours are wrt the last 24h of data.)

This page updated at Fri Apr 12 17:01:07 UTC 2024; generation time 5398ms.

See also:

Poll every 10 minutes for 404 HTTP status code (404 means green, 200 means not green, anything else is 'unknown' status due to server/network/other problems) for automated systems:

Please email me if you use this mechanism, to be alerted to changes.

See code on GitHub.

This free service may be unavailable or withdrawn at any time and is provided "as-is" with no warranties of any kind.
Some data used to generate this page is licensed from ELEXON.
Copyright © Damon Hart-Davis 2010--2024. [home]