Statistics
Page built 2026-09-21
Data as of 2026-09-19
Search
Built 2026-09-21 (21 September 2026)

ISO-NE Daily Load Shape and Duck Curve by Hour, 22 August to 19 September 2026

In the 29 complete local days from 22 August to 19 September 2026, electricity demand in ISO-NE averaged 13,018 MW and typically peaked at 19:00 local time (15,986 MW) and bottomed out at 03:00 (11,511 MW). With solar and wind taken off, the remaining load fell to 10,415 MW at 10:00 and then rose 3,036 MW between 14:00 to 17:00. Hours are local clock time (America/New_York).

Key Facts

  • Over 29 complete local days from 22 August to 19 September 2026, average demand in ISO-NE was 13,018 MW. The hour of the day with the highest average demand was 19:00 local time (15,986 MW) and the lowest was 03:00 (11,511 MW).
  • The largest three hour rise in average demand was 2,649 MW, between 14:00 to 17:00 local time.
  • The single highest hour of demand in the 30 day window was 19,017 MW, in the hour starting 28 Aug 2026, 18:00 EDT (UTC-04:00).
  • Solar output averaged 773 MW at its 12:00 peak, 6% of average demand.
  • Demand minus solar and wind (net load) averaged 12,062 MW, fell to 10,415 MW at 10:00 and rose 3,036 MW over the three hours from 14:00 to 17:00, 23% of average demand.

Average Day by Local Hour

29 days to 2026-09-19, America/New_York time
ISO-NE average demand and net generation by local hour Average electricity demand in ISO-NE by local clock hour over 29 complete local days from 22 August to 19 September 2026. It was lowest at 03:00 (11,511 MW) and highest at 19:00 (15,986 MW). Net generation is the power produced inside the grid, so it differs from demand by net imports. 0 5,000 10,000 15,000 20,000 00:0003:0006:0009:0012:0015:0018:0021:00
Average electricity demand in ISO-NE by local clock hour over 29 complete local days from 22 August to 19 September 2026. It was lowest at 03:00 (11,511 MW) and highest at 19:00 (15,986 MW). Net generation is the power produced inside the grid, so it differs from demand by net imports.
Mean MW by local hour, 2026-08-22 to 2026-09-19
ISO-NE average demand and net generation by local hour
Local hour (America/New_York)DemandNet generation
00:0012,153 MW11,971 MW
01:0011,896 MW11,595 MW
02:0011,634 MW11,280 MW
03:0011,511 MW11,181 MW
04:0011,576 MW11,202 MW
05:0011,857 MW11,497 MW
06:0012,310 MW12,036 MW
07:0012,586 MW12,286 MW
08:0012,334 MW12,327 MW
09:0011,967 MW12,329 MW
10:0011,681 MW12,402 MW
11:0011,781 MW12,573 MW
12:0012,036 MW12,758 MW
13:0012,392 MW13,007 MW
14:0012,794 MW13,337 MW
15:0013,477 MW13,715 MW
16:0014,390 MW14,334 MW
17:0015,443 MW15,132 MW
18:0015,984 MW15,464 MW
19:0015,986 MW15,413 MW
20:0015,550 MW14,788 MW
21:0014,715 MW14,214 MW
22:0013,668 MW13,406 MW
23:0012,723 MW12,654 MW
ISO-NE duck curve: demand and net load by local hour Average demand and net load (demand minus solar and wind) in ISO-NE by local clock hour over 29 complete local days from 22 August to 19 September 2026. Net load was lowest at 10:00 (10,415 MW) and then rose 3,036 MW between 14:00 to 17:00. 0 5,000 10,000 15,000 20,000 00:0003:0006:0009:0012:0015:0018:0021:00
Average demand and net load (demand minus solar and wind) in ISO-NE by local clock hour over 29 complete local days from 22 August to 19 September 2026. Net load was lowest at 10:00 (10,415 MW) and then rose 3,036 MW between 14:00 to 17:00.
Mean MW by local hour, 2026-08-22 to 2026-09-19
ISO-NE duck curve: demand and net load by local hour
Local hour (America/New_York)DemandNet load (demand minus solar and wind)
00:0012,153 MW11,353 MW
01:0011,896 MW11,068 MW
02:0011,634 MW10,844 MW
03:0011,511 MW10,716 MW
04:0011,576 MW10,792 MW
05:0011,857 MW11,083 MW
06:0012,310 MW11,552 MW
07:0012,586 MW11,750 MW
08:0012,334 MW11,343 MW
09:0011,967 MW10,819 MW
10:0011,681 MW10,415 MW
11:0011,781 MW10,463 MW
12:0012,036 MW10,686 MW
13:0012,392 MW11,108 MW
14:0012,794 MW11,468 MW
15:0013,477 MW12,226 MW
16:0014,390 MW13,280 MW
17:0015,443 MW14,504 MW
18:0015,984 MW15,208 MW
19:0015,986 MW15,233 MW
20:0015,550 MW14,770 MW
21:0014,715 MW13,944 MW
22:0013,668 MW12,894 MW
23:0012,723 MW11,963 MW
ISO-NE average solar and wind output by local hour Average solar and wind generation in ISO-NE by local clock hour over 29 complete local days from 22 August to 19 September 2026. Solar peaked at 12:00 at 773 MW. 0 250 500 750 1,000 00:0003:0006:0009:0012:0015:0018:0021:00
Average solar and wind generation in ISO-NE by local clock hour over 29 complete local days from 22 August to 19 September 2026. Solar peaked at 12:00 at 773 MW.
Mean MW by local hour, 2026-08-22 to 2026-09-19
ISO-NE average solar and wind output by local hour
Local hour (America/New_York)SolarWind
00:004 MW796 MW
01:005 MW823 MW
02:005 MW785 MW
03:004 MW791 MW
04:005 MW779 MW
05:005 MW769 MW
06:0014 MW743 MW
07:00128 MW708 MW
08:00354 MW637 MW
09:00568 MW579 MW
10:00706 MW561 MW
11:00763 MW555 MW
12:00773 MW578 MW
13:00715 MW569 MW
14:00702 MW624 MW
15:00603 MW648 MW
16:00458 MW651 MW
17:00267 MW672 MW
18:0076 MW700 MW
19:0013 MW739 MW
20:009 MW771 MW
21:007 MW764 MW
22:006 MW768 MW
23:005 MW755 MW
Average ISO-NE demand, net generation, solar, wind and net load by local hour
Local hourDemandNet generationSolarWindNet load
00:00 12,153 MW 11,971 MW 4 MW 796 MW 11,353 MW
01:00 11,896 MW 11,595 MW 5 MW 823 MW 11,068 MW
02:00 11,634 MW 11,280 MW 5 MW 785 MW 10,844 MW
03:00 11,511 MW 11,181 MW 4 MW 791 MW 10,716 MW
04:00 11,576 MW 11,202 MW 5 MW 779 MW 10,792 MW
05:00 11,857 MW 11,497 MW 5 MW 769 MW 11,083 MW
06:00 12,310 MW 12,036 MW 14 MW 743 MW 11,552 MW
07:00 12,586 MW 12,286 MW 128 MW 708 MW 11,750 MW
08:00 12,334 MW 12,327 MW 354 MW 637 MW 11,343 MW
09:00 11,967 MW 12,329 MW 568 MW 579 MW 10,819 MW
10:00 11,681 MW 12,402 MW 706 MW 561 MW 10,415 MW
11:00 11,781 MW 12,573 MW 763 MW 555 MW 10,463 MW
12:00 12,036 MW 12,758 MW 773 MW 578 MW 10,686 MW
13:00 12,392 MW 13,007 MW 715 MW 569 MW 11,108 MW
14:00 12,794 MW 13,337 MW 702 MW 624 MW 11,468 MW
15:00 13,477 MW 13,715 MW 603 MW 648 MW 12,226 MW
16:00 14,390 MW 14,334 MW 458 MW 651 MW 13,280 MW
17:00 15,443 MW 15,132 MW 267 MW 672 MW 14,504 MW
18:00 15,984 MW 15,464 MW 76 MW 700 MW 15,208 MW
19:00 15,986 MW 15,413 MW 13 MW 739 MW 15,233 MW
20:00 15,550 MW 14,788 MW 9 MW 771 MW 14,770 MW
21:00 14,715 MW 14,214 MW 7 MW 764 MW 13,944 MW
22:00 13,668 MW 13,406 MW 6 MW 768 MW 12,894 MW
23:00 12,723 MW 12,654 MW 5 MW 755 MW 11,963 MW

Each value is the mean over 29 complete local days from 22 August to 19 September 2026, weekdays and weekends together, for the hour starting at that local clock time. Net load is demand minus solar and wind generation. The single highest hour of demand in the whole 30 day window was 19,017 MW; it is a published reading, not an average, and is not part of the profile above.

Source: U.S. Energy Information Administration (EIA). (US Government work, public domain) Data as of 2026-09-19. Profiles are computed by World Power Monitor from the operator's hourly series.

Assumptions

  • Hours are local clock time in America/New_York. A local day is used only if it is whole inside the 30 day window and at least 22 of its hours are complete; the profile uses the 29 most recent such days. Daylight saving follows the local clock: on a clock change day the missing hour is absent and the repeated hour is averaged over both readings.
  • The average mixes weekdays and weekends and covers only 29 days, so it describes recent conditions, not a seasonal norm.
  • The evening ramp is the largest rise over three hours in the average profile, starting between 14:00 and 20:00 local time.