Earth Notes: On Variations in GB Grid Electricity CO2 Intensity By Year

See CO2 emissions from each GB grid kWh, analysed by year, 2009--2015.
GB grid intensity
Jump to full-year analysis for:

Historical Survey of Full-Year 2009 Data

The fuel-mix (FUELINST) data is only available from Nov 2008, so here is an initial analysis for the whole of 2009. (I intend to update this periodically with new data.) This is generation intensity, ie ignoring transmission/distribution losses.

Note how carbon intensity is higher during the day, during the working week, and in the colder winter months, all where demand is highest; ie there is a fairly clear correlation between demand and intensity.

Note also how the mean variability (ie the maximum available CO2 savings from load-shifting) during each day varies from a low of 8% mid-winter to more than 4 times that in summer/autumn. My assumption is that nuclear (baseload) and renewables (zero carbon) are effectively used preferentially in the grid, but demand above their generation is satisfied by increasingly carbon-intense fuels, firstly gas (eg relatively-clean CCGT) all the way up to coal. In winter the zero/low carbon fuels make only a relatively small dent, but moving towards summer at night they cover a large chunk of demand and bring carbon intensity down further than is possible in winter.

It seems to be a good idea from an intensity point of view as well as an infrastructure-sizing and cost point of view to avoid running deferrable load at times of peak demand. If you can delay major loads (such as the dishwasher or washing machine at home) until late in the evening or the small hours after midnight you will probably significantly reduce your carbon footprint.

Note, however, that if the only reduction is a virtual one because of relatively fixed non-dispatchable zero-carbon generation (nuclear), then in order to achieve real footprint/emission reductions, and not just make everyone else's consumption higher/browner, you may have to defer load until other zero-carbon sources do increase output eg because the wind is blowing stronger or the sun shining brightly, rather just when zero/low carbon sources happen passively to form a higher proportion of extant demand. Having said that, if the demand curve becomes flatter though behaviour changes, then it will be possible to have (for example) more nuclear in the mix, and reduce the inherent waste of energy in using (eg pumped) storage, which would reduce long-term carbon footprint through requiring less fossil-fuel peak-demand support. This area requires more analysis.

Input data runs from Thu Jan 01 00:00:00 GMT 2009 to Thu Dec 31 23:55:00 GMT 2009.

Data Analysed By Hour-of-Day (GMT)

QtyHour-of-Day (GMT)
Bucket000102030405060708091011121314151617181920212223
Sample Count438043704368436843684368436843764376433142694286433143574368436743644368436843684368436843684368
Max gCO2/kWh604607603603596599600601598591589589592602595595590575587590593601602600
Mean gCO2/kWh
  • 375
  • 372
  • 368
  • 366
  • 368
  • 386
  • 419
  • 444
  • 456
  • 463
  • 465
  • 466
  • 465
  • 463
  • 460
  • 460
  • 465
  • 463
  • 458
  • 454
  • 446
  • 429
  • 398
  • 377
Min gCO2/kWh229229227230234233235236250272280287247277270270277282280284285257237229
Variability63%63%63%62%61%62%61%61%59%54%53%52%59%54%55%55%54%51%53%52%52%58%61%62%

Data Analysed By Week/Weekend

QtyWeek/Weekend
BucketWeekWeekend
Sample Count7471429877
Max gCO2/kWh607584
Mean gCO2/kWh
  • 445
  • 387
Min gCO2/kWh234227
Variability62%62%
Mean variability (available CO2 savings from load-shifting) during each Day28%24%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day138g99g

Data Analysed By Month

QtyMonth
Bucket010203040506070809101112
Sample Count890180648822860489288605892089018604878385618898
Max gCO2/kWh607593540508525494503484519545547544
Mean gCO2/kWh
  • 561
  • 519
  • 450
  • 393
  • 395
  • 394
  • 374
  • 354
  • 390
  • 446
  • 417
  • 453
Min gCO2/kWh471390291276272247234231227297266309
Variability23%35%47%46%49%50%54%53%57%46%52%44%
Mean variability (available CO2 savings from load-shifting) during each Day8%12%22%29%28%31%32%34%35%31%36%25%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day46g65g105g132g127g137g139g141g161g160g179g126g

Data Analysed By Year

QtyYear
Bucket2009
Sample Count104591
Max gCO2/kWh607
Mean gCO2/kWh
  • 428
Min gCO2/kWh227
Variability63%
Mean variability (available CO2 savings from load-shifting) during each Day27%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day127g

Data Analysed By EachHour

Datum count: 8724

Range: 2009/01/01 00:00 to 2009/12/31 23:00; all times UTC.

See CSV file for full data set...

Other Analysis

Correlation of demand against grid intensity: 0.8660.

Correlation of fuel use against demand (+ve implies that this fuel use corresponds to demand): CCGT=0.5651 COAL=0.9180 INTFR=-0.1421 INTIRL=-0.3996 NPSHYD=0.6066 NUCLEAR=-0.1435 OCGT=0.1892 OIL=0.6604 PS=0.3952 WIND=0.0523.

Correlation of fuel use against grid intensity (-ve implies that this fuel reduces grid intensity for non-callable sources): CCGT=0.2461 COAL=0.9735 INTFR=-0.2110 INTIRL=-0.3704 NPSHYD=0.4422 NUCLEAR=-0.3301 OCGT=0.1661 OIL=0.4989 PS=0.2331 WIND=-0.0036.

Generation Fuel Intensities Used

CCGT=0.36 COAL=0.91 INTEW=0.45 INTFR=0.09 INTIRL=0.7 INTNED=0.55 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.48 OIL=0.61 OTHER=0.61 WIND=0.0.

Report generated at Sat Jan 19 19:56:58 GMT 2013, generation time 23064ms.

Historical Survey of Full-Year 2010 Data

Here is the 2010 analysis: note that mean generation intensity for the year seems to have risen from 428gCO2/kWh in 2009 to 444gCO2/kWh in 2010, with less scope for emissions savings from load shifting.

(All intensity figures are for generation unless otherwise stated. Until 2011/09/14, ie up to and including these 2010 figures, I have been using DEFRA's suggested values of 2% transmission losses and 7% distribution losses for a total of 9% losses, though a 5% distribution loss now appears to be a better estimate. According to "Annette", thank you, distribution losses range from from 3.7% for Yorkshire area to 8% for Scottish Hydro. Also, to be clear, intensities used up to and including these figures are: CCGT=0.36 COAL=0.91 INTFR=0.09 INTIRL=0.7 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.48 OIL=0.61 OTHER=0.61 WIND=0.0.)

Possible initial explanations:

The numbers may simply be slightly wrong due to a number of factors, eg:

Input data runs from Fri Jan 01 00:00:00 GMT 2010 to Fri Dec 31 23:55:00 GMT 2010.

Data Analysed By Hour-of-Day (GMT)

QtyHour-of-Day (GMT)
Bucket000102030405060708091011121314151617181920212223
Sample Count437343714368436743684382438043804376434743204330434643824380437343674368438143804380437043584367
Max gCO2/kWh568570569571567565561564565621563563564563563562560561558559563568571567
Mean gCO2/kWh
  • 396
  • 392
  • 388
  • 386
  • 391
  • 409
  • 439
  • 460
  • 469
  • 474
  • 476
  • 476
  • 476
  • 474
  • 471
  • 471
  • 472
  • 471
  • 466
  • 464
  • 459
  • 446
  • 419
  • 399
Min gCO2/kWh266265262261262268281283300316334342341334331333337336324321322313296271
Variability54%54%54%55%54%53%50%50%47%50%41%40%40%41%42%41%40%41%42%43%43%45%49%53%

Data Analysed By Week/Weekend

QtyWeek/Weekend
BucketWeekWeekend
Sample Count7488429930
Max gCO2/kWh621556
Mean gCO2/kWh
  • 458
  • 408
Min gCO2/kWh275261
Variability56%54%
Mean variability (available CO2 savings from load-shifting) during each Day25%21%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day122g93g

Data Analysed By Month

QtyMonth
Bucket010203040506070809101112
Sample Count889780648892863988098638890189028633889386408906
Max gCO2/kWh563548553520523518621508565537571571
Mean gCO2/kWh
  • 488
  • 486
  • 419
  • 412
  • 412
  • 411
  • 420
  • 391
  • 435
  • 450
  • 485
  • 515
Min gCO2/kWh352339282295275292283263287261335430
Variability38%39%50%44%48%44%55%49%50%52%42%25%
Mean variability (available CO2 savings from load-shifting) during each Day17%16%26%27%27%32%28%28%28%26%20%10%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day87g81g120g124g123g155g132g123g135g128g106g51g

Data Analysed By Year

QtyYear
Bucket2010
Sample Count104814
Max gCO2/kWh621
Mean gCO2/kWh
  • 444
Min gCO2/kWh261
Variability58%
Mean variability (available CO2 savings from load-shifting) during each Day24%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day114g

Data Analysed By EachHour

Datum count: 8741

Range: 2010/01/01 00:00 to 2010/12/31 23:00; all times UTC.

See CSV file for full data set...

Other Analysis

Correlation of demand against grid intensity: 0.8532.

Correlation of fuel use against demand (+ve implies that this fuel use corresponds to demand): CCGT=0.7412 COAL=0.9344 INTFR=-0.2906 INTIRL=-0.0665 NPSHYD=0.4151 NUCLEAR=0.5051 OCGT=0.1508 OIL=0.4116 PS=0.3717 WIND=0.0678.

Correlation of fuel use against grid intensity (-ve implies that this fuel reduces grid intensity for non-callable sources): CCGT=0.4360 COAL=0.9571 INTFR=-0.3890 INTIRL=0.0380 NPSHYD=0.3238 NUCLEAR=0.3204 OCGT=0.1121 OIL=0.0457 PS=0.1925 WIND=0.0334.

Generation Fuel Intensities Used

CCGT=0.36 COAL=0.91 INTEW=0.45 INTFR=0.09 INTIRL=0.7 INTNED=0.55 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.48 OIL=0.61 OTHER=0.61 WIND=0.0.

Report generated at Sat Jan 19 19:48:25 GMT 2013, generation time 21457ms.

Historical Survey of Full-Year 2011 Data

Stefan Adamof at Edinburgh University has kindly provided an example chart using the hourly intensity data that I have started extracting 2013/01, for use in the CHARM project.

Input data runs from Sat Jan 01 00:00:00 GMT 2011 to Sat Dec 31 23:55:00 GMT 2011.

Data Analysed By Hour-of-Day (GMT)

QtyHour-of-Day (GMT)
Bucket000102030405060708091011121314151617181920212223
Sample Count437643804374436843684368436643664366433643004318435543684368436843684368436843684368436643684365
Max gCO2/kWh575575569570572588587581580578580583586590588586573565573579583589596591
Mean gCO2/kWh
  • 397
  • 392
  • 387
  • 384
  • 388
  • 406
  • 431
  • 450
  • 458
  • 463
  • 464
  • 464
  • 464
  • 462
  • 460
  • 461
  • 460
  • 458
  • 454
  • 453
  • 449
  • 439
  • 418
  • 401
Min gCO2/kWh245240233224214214232250280302307303298288288290293293290293302273249243
Variability58%59%60%61%63%64%61%57%52%48%48%49%50%52%52%51%49%49%50%50%49%54%59%59%

Data Analysed By Week/Weekend

QtyWeek/Weekend
BucketWeekWeekend
Sample Count7446930215
Max gCO2/kWh596581
Mean gCO2/kWh
  • 449
  • 404
Min gCO2/kWh240214
Variability60%64%
Mean variability (available CO2 savings from load-shifting) during each Day23%22%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day108g93g

Data Analysed By Month

QtyMonth
Bucket010203040506070809101112
Sample Count892680458926863889108615892689288630885786408643
Max gCO2/kWh546538540477469523480527505543596590
Mean gCO2/kWh
  • 476
  • 470
  • 475
  • 374
  • 371
  • 396
  • 386
  • 400
  • 414
  • 451
  • 518
  • 502
Min gCO2/kWh315327363240214249261246270305345298
Variability43%40%33%50%55%53%46%54%47%44%43%50%
Mean variability (available CO2 savings from load-shifting) during each Day14%18%16%26%28%27%26%28%27%23%17%18%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day72g90g81g108g117g118g110g126g124g112g92g95g

Data Analysed By Year

QtyYear
Bucket2011
Sample Count104684
Max gCO2/kWh596
Mean gCO2/kWh
  • 436
Min gCO2/kWh214
Variability65%
Mean variability (available CO2 savings from load-shifting) during each Day22%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day104g

Data Analysed By EachHour

Datum count: 8734

Range: 2011/01/01 00:00 to 2011/12/31 23:00; all times UTC.

See CSV file for full data set...

Other Analysis

Correlation of demand against grid intensity: 0.7809.

Correlation of fuel use against demand (+ve implies that this fuel use corresponds to demand): CCGT=0.6598 COAL=0.8823 INTFR=0.0861 INTNED=-0.1022 NPSHYD=0.4247 NUCLEAR=0.1300 OCGT=0.2477 OIL=0.1690 PS=0.3698 WIND=0.0389.

Correlation of fuel use against grid intensity (-ve implies that this fuel reduces grid intensity for non-callable sources): CCGT=0.2343 COAL=0.9526 INTFR=0.0137 INTNED=-0.1327 NPSHYD=0.4063 NUCLEAR=-0.1644 OCGT=0.3089 OIL=0.3661 PS=0.1657 WIND=0.0614.

Generation Fuel Intensities Used

CCGT=0.36 COAL=0.91 INTEW=0.45 INTFR=0.09 INTIRL=0.7 INTNED=0.55 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.48 OIL=0.61 OTHER=0.61 WIND=0.0.

Report generated at Sat Jan 19 19:42:04 GMT 2013, generation time 23740ms.

Historical Survey of Full-Year 2012 Data

Capacity of WIND up significantly this year, but so was burning of COAL due to good "dark spread" vs "spark spread" and Large Combustion Plant Directive deadline drawing near, so mean grid intensity was significantly up from last year. (Though more embedded renewables, and possibly biomass cofiring not reflected in these numbers properly, probably means that this overstates the case.)

Note that apparent available savings from load-shifting are falling year-on-year also.

Input data runs from Sun Jan 01 00:00:00 GMT 2012 to Mon Dec 31 23:55:00 GMT 2012.

Data Analysed By Hour-of-Day (GMT)

QtyHour-of-Day (GMT)
Bucket000102030405060708091011121314151617181920212223
Sample Count439243924392439243864390438743924392435943354356438143904392439143924392439243924392439243924392
Max gCO2/kWh614617606605603629617603596589590593593588588589586582577578594596611608
Mean gCO2/kWh
  • 481
  • 477
  • 472
  • 468
  • 472
  • 487
  • 498
  • 503
  • 504
  • 504
  • 504
  • 504
  • 506
  • 507
  • 507
  • 505
  • 502
  • 501
  • 501
  • 503
  • 506
  • 505
  • 496
  • 486
Min gCO2/kWh311298300289283293297306288310357387385392394398399409411398390381343335
Variability50%52%51%53%54%54%52%50%52%48%40%35%36%34%33%33%32%30%29%32%35%37%44%45%

Data Analysed By Week/Weekend

QtyWeek/Weekend
BucketWeekWeekend
Sample Count7502330232
Max gCO2/kWh629603
Mean gCO2/kWh
  • 503
  • 477
Min gCO2/kWh308283
Variability52%54%
Mean variability (available CO2 savings from load-shifting) during each Day16%16%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day82g77g

Data Analysed By Month

QtyMonth
Bucket010203040506070809101112
Sample Count892883498903864088818616892689278614892886168927
Max gCO2/kWh587608629586542533539521551602612575
Mean gCO2/kWh
  • 496
  • 530
  • 552
  • 508
  • 475
  • 451
  • 464
  • 439
  • 467
  • 535
  • 528
  • 506
Min gCO2/kWh288414477373338312316283328397437325
Variability51%32%25%37%38%42%42%46%41%35%29%44%
Mean variability (available CO2 savings from load-shifting) during each Day20%12%10%13%14%20%15%21%25%12%13%14%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day108g64g56g65g67g93g75g98g128g69g71g73g

Data Analysed By Year

QtyYear
Bucket2012
Sample Count105255
Max gCO2/kWh629
Mean gCO2/kWh
  • 496
Min gCO2/kWh283
Variability56%
Mean variability (available CO2 savings from load-shifting) during each Day16%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day80g

Data Analysed By EachHour

Datum count: 8778

Range: 2012/01/01 00:00 to 2012/12/31 23:00; all times UTC.

See CSV file for full data set...

Other Analysis

Correlation of demand against grid intensity: 0.5560.

Correlation of fuel use against demand (+ve implies that this fuel use corresponds to demand): CCGT=0.8320 COAL=0.8644 INTEW=0.4262 INTFR=-0.1407 INTIRL=0.1017 INTNED=-0.1421 NPSHYD=0.6162 NUCLEAR=0.0082 OCGT=0.3345 OIL=0.1618 OTHER=0.3017 PS=0.3401 WIND=0.1111.

Correlation of fuel use against grid intensity (-ve implies that this fuel reduces grid intensity for non-callable sources): CCGT=0.2758 COAL=0.8579 INTEW=0.4858 INTFR=-0.4193 INTIRL=0.0045 INTNED=-0.1158 NPSHYD=0.2848 NUCLEAR=-0.3655 OCGT=0.2252 OIL=0.2571 OTHER=0.2185 PS=0.0475 WIND=-0.2111.

Generation Fuel Intensities Used

CCGT=0.36 COAL=0.91 INTEW=0.45 INTFR=0.09 INTIRL=0.45 INTNED=0.55 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.48 OIL=0.61 OTHER=0.3 WIND=0.0.

Report generated at Sat Jan 19 16:40:48 GMT 2013, generation time 61230ms.

Historical Survey of Full-Year 2013 Data

Input data runs from Tue Jan 01 00:00:00 GMT 2013 to Tue Dec 31 23:55:00 GMT 2013.

Data Analysed By Hour-of-Day (GMT)

QtyHour-of-Day (GMT)
Bucket000102030405060708091011121314151617181920212223
Sample Count435643564356435643564356435643564356434243174312435343564356435643564356435643564356435643574368
Max gCO2/kWh588593597605603601589585595586570567571577577574570559551551563582592590
Mean gCO2/kWh
  • 467
  • 465
  • 461
  • 457
  • 458
  • 467
  • 472
  • 472
  • 473
  • 473
  • 472
  • 473
  • 474
  • 475
  • 475
  • 473
  • 470
  • 469
  • 468
  • 470
  • 473
  • 476
  • 474
  • 468
Min gCO2/kWh269277275265260276272285310325337340334328327327329324322322320297272267
Variability55%54%54%57%57%55%54%52%48%45%41%41%42%44%44%44%43%43%42%42%44%49%55%55%

Data Analysed By Week/Weekend

QtyWeek/Weekend
BucketWeekWeekend
Sample Count7479329664
Max gCO2/kWh605595
Mean gCO2/kWh
  • 474
  • 459
Min gCO2/kWh269260
Variability56%57%
Mean variability (available CO2 savings from load-shifting) during each Day13%16%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day67g75g

Data Analysed By Month

QtyMonth
Bucket010203040506070809101112
Sample Count890877768928864088988640892889288608891083658928
Max gCO2/kWh574590605560545532481518559551531538
Mean gCO2/kWh
  • 500
  • 511
  • 517
  • 474
  • 479
  • 439
  • 434
  • 436
  • 468
  • 472
  • 467
  • 444
Min gCO2/kWh363417439363326260335274325336316293
Variability37%30%28%36%41%52%31%48%42%40%41%46%
Mean variability (available CO2 savings from load-shifting) during each Day12%10%10%14%14%15%10%18%17%16%13%19%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day63g56g53g71g70g67g46g82g86g79g64g91g

Data Analysed By Year

QtyYear
Bucket2013
Sample Count104457
Max gCO2/kWh605
Mean gCO2/kWh
  • 470
Min gCO2/kWh260
Variability58%
Mean variability (available CO2 savings from load-shifting) during each Day14%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day69g

Data Analysed By EachHour

Datum count: 8710

Range: 2013/01/01 00:00 to 2013/12/31 23:00; all times UTC.

See CSV file for full data set...

Other Analysis

Correlation of demand against grid intensity: 0.4122.

Correlation of fuel use against demand (+ve implies that this fuel use corresponds to demand): CCGT=0.8525 COAL=0.8069 INTEW=0.0315 INTFR=-0.2671 INTIRL=0.0974 INTNED=0.0755 NPSHYD=0.4787 NUCLEAR=0.1413 OCGT=0.2860 OIL=-0.1536 OTHER=0.2852 PS=0.3090 WIND=0.1173.

Correlation of fuel use against grid intensity (-ve implies that this fuel reduces grid intensity for non-callable sources): CCGT=0.2675 COAL=0.7851 INTEW=-0.2328 INTFR=-0.4717 INTIRL=-0.0158 INTNED=-0.0179 NPSHYD=-0.0152 NUCLEAR=-0.1897 OCGT=0.2472 OIL=-0.0296 OTHER=0.1541 PS=-0.0008 WIND=-0.3443.

Generation Fuel Intensities Used

CCGT=0.36 COAL=0.91 INTEW=0.45 INTFR=0.09 INTIRL=0.45 INTNED=0.55 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.48 OIL=0.61 OTHER=0.3 WIND=0.0.

Report generated at Tue May 20 12:36:33 BST 2014, generation time 30850ms.

Historical Survey of Full-Year 2014 Data

Input data runs from Wed Jan 01 00:00:00 GMT 2014 to Wed Dec 31 23:55:00 GMT 2014.

Data Analysed By Hour-of-Day (GMT)

QtyHour-of-Day (GMT)
Bucket000102030405060708091011121314151617181920212223
Sample Count438043804380438043804380438043804380436443434345437343794379438043794380438043724356435643704380
Max gCO2/kWh543547552552544538532524516507508513518521521522518511504508520533533542
Mean gCO2/kWh
  • 404
  • 403
  • 397
  • 392
  • 391
  • 404
  • 418
  • 425
  • 428
  • 430
  • 431
  • 431
  • 432
  • 432
  • 430
  • 430
  • 428
  • 427
  • 425
  • 425
  • 427
  • 426
  • 419
  • 407
Min gCO2/kWh185185186197201211228245261268261255255252249258242261254247241217195186
Variability66%67%67%65%64%61%58%54%50%48%49%51%51%52%53%51%54%49%50%52%54%60%64%66%

Data Analysed By Week/Weekend

QtyWeek/Weekend
BucketWeekWeekend
Sample Count7503529921
Max gCO2/kWh546552
Mean gCO2/kWh
  • 425
  • 404
Min gCO2/kWh185186
Variability67%67%
Mean variability (available CO2 savings from load-shifting) during each Day18%19%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day80g83g

Data Analysed By Month

QtyMonth
Bucket010203040506070809101112
Sample Count892880648912861488988640889989288604892686158928
Max gCO2/kWh552534542546472445440424514519535506
Mean gCO2/kWh
  • 460
  • 451
  • 472
  • 447
  • 410
  • 359
  • 337
  • 332
  • 449
  • 437
  • 461
  • 421
Min gCO2/kWh303312361322273232256185359249242251
Variability46%42%34%42%43%48%42%57%31%53%55%51%
Mean variability (available CO2 savings from load-shifting) during each Day16%18%13%17%18%22%23%24%13%20%16%22%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day77g84g67g82g77g86g83g84g59g95g80g98g

Data Analysed By Year

QtyYear
Bucket2014
Sample Count104956
Max gCO2/kWh552
Mean gCO2/kWh
  • 419
Min gCO2/kWh185
Variability67%
Mean variability (available CO2 savings from load-shifting) during each Day18%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day81g

Data Analysed By EachHour

Datum count: 8753

Range: 2014/01/01 00:00 to 2014/12/31 23:00; all times UTC.

See CSV file for full data set...

Other Analysis

Correlation of demand against grid intensity: 0.5314.

Correlation of fuel use against demand (+ve implies that this fuel use corresponds to demand): CCGT=0.6606 COAL=0.7363 INTEW=-0.1058 INTFR=0.0931 INTIRL=-0.1731 INTNED=0.1526 NPSHYD=0.6039 NUCLEAR=0.0215 OCGT=0.2828 OIL=0.2949 OTHER=0.1291 PS=0.4224 WIND=0.1860.

Correlation of fuel use against grid intensity (-ve implies that this fuel reduces grid intensity for non-callable sources): CCGT=0.0414 COAL=0.8949 INTEW=-0.1639 INTFR=-0.0758 INTIRL=-0.1736 INTNED=0.1122 NPSHYD=0.4808 NUCLEAR=-0.2720 OCGT=0.1487 OIL=-0.3232 OTHER=0.0300 PS=0.1148 WIND=-0.0507.

Generation Fuel Intensities Used

CCGT=0.36 COAL=0.91 INTEW=0.45 INTFR=0.09 INTIRL=0.45 INTNED=0.55 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.48 OIL=0.61 OTHER=0.3 WIND=0.0.

Report generated at Sun Jan 18 12:22:22 GMT 2015, generation time 42071ms.

Historical Survey of Full-Year 2015 Data

Overall mean intensity dropped from 419gCO2/kWh in 2014 to 367gCO2/kWh, but also note the general fall in intensity after April when lots of coal generation went off-line, bringing winter means down from something like 430gCO2/kWh in 2014 to more like 340gCO2/kWh.

Input data runs from Thu Jan 01 00:00:00 GMT 2015 to Thu Dec 31 23:55:00 GMT 2015.

Data Analysed By Hour-of-Day (GMT)

QtyHour-of-Day (GMT)
Bucket000102030405060708091011121314151617181920212223
Sample Count438043804380438043804380437243684368436643534350436043804380438043804380438043804380438043804380
Max gCO2/kWh512502504508506517519506501521521504510512510509504501500497497502506511
Mean gCO2/kWh
  • 340
  • 339
  • 335
  • 331
  • 333
  • 345
  • 363
  • 375
  • 380
  • 382
  • 382
  • 382
  • 381
  • 379
  • 379
  • 383
  • 387
  • 388
  • 387
  • 385
  • 382
  • 374
  • 360
  • 343
Min gCO2/kWh181183161155153162173170185204228220223217215229257259254252240231207183
Variability65%64%69%70%70%69%67%67%64%61%57%57%57%58%58%56%50%49%50%50%52%54%60%65%

Data Analysed By Week/Weekend

QtyWeek/Weekend
BucketWeekWeekend
Sample Count7504829949
Max gCO2/kWh519521
Mean gCO2/kWh
  • 374
  • 351
Min gCO2/kWh155153
Variability71%71%
Mean variability (available CO2 savings from load-shifting) during each Day24%25%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day94g97g

Data Analysed By Month

QtyMonth
Bucket010203040506070809101112
Sample Count888980648899864089288640890389288640892886138925
Max gCO2/kWh482506521512435405409415415462449428
Mean gCO2/kWh
  • 417
  • 436
  • 439
  • 407
  • 340
  • 342
  • 337
  • 329
  • 342
  • 382
  • 341
  • 301
Min gCO2/kWh269320301246206208153202193244155165
Variability45%37%43%52%53%49%63%52%54%48%66%62%
Mean variability (available CO2 savings from load-shifting) during each Day20%16%17%19%25%21%26%26%26%27%31%35%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day87g73g78g83g91g78g96g92g98g116g120g121g

Data Analysed By Year

QtyYear
Bucket2015
Sample Count104997
Max gCO2/kWh521
Mean gCO2/kWh
  • 367
Min gCO2/kWh153
Variability71%
Mean variability (available CO2 savings from load-shifting) during each Day24%
Mean available CO2 savings per kWh from load-shifting, eg ~1 wash load, during each Day95g

Data Analysed By EachHour

Datum count: 8755

Range: 2015/01/01 00:00 to 2015/12/31 23:00; all times UTC.

See CSV file for full data set...

Other Analysis

Correlation of demand against grid intensity: 0.6568.

Correlation of fuel use against demand (+ve implies that this fuel use corresponds to demand): CCGT=0.7768 COAL=0.7895 INTEW=-0.2728 INTFR=-0.0228 INTIRL=-0.4413 INTNED=0.3802 NPSHYD=0.5031 NUCLEAR=0.3128 OCGT=0.6090 OIL=-0.0502 OTHER=0.0375 PS=0.3621 WIND=0.1207.

Correlation of fuel use against grid intensity (-ve implies that this fuel reduces grid intensity for non-callable sources): CCGT=0.3993 COAL=0.9067 INTEW=-0.2654 INTFR=-0.0340 INTIRL=-0.2984 INTNED=0.3902 NPSHYD=0.1632 NUCLEAR=0.0893 OCGT=0.4635 OIL=0.1615 OTHER=-0.2580 PS=0.1322 WIND=-0.3234.

Generation Fuel Intensities Used

CCGT=0.36 COAL=0.91 INTEW=0.45 INTFR=0.09 INTIRL=0.45 INTNED=0.55 NPSHYD=0.0 NUCLEAR=0.0 OCGT=0.48 OIL=0.61 OTHER=0.3 WIND=0.0.

Report generated at Sun Jan 17 15:08:02 GMT 2016, generation time 15029ms.