Netherlands Demand Forecast Accuracy: Error, Bias and Worst Miss, 23 August to 20 September 2026
The day-ahead demand forecast for Netherlands was off by 26.8% on average (mean absolute percentage error) over 673 hours from 23 August to 20 September 2026, and 13% of hours landed within 5% of the reading. Its bias was +25.2%: it ran high on average, an over forecast. The largest miss was 8,217 MW (281.3%) too high at 6 Sept 2026, 11:00 CEST (UTC+02:00). Dates and times are local (Europe/Amsterdam).
Key Facts
- The day-ahead demand forecast for Netherlands was off by 26.8% on average (mean absolute percentage error) over 673 hours from 23 August to 20 September 2026, and 13% of hours landed within 5% of the reading. Its bias was +25.2%: it ran high on average, an over forecast. The largest miss was 8,217 MW (281.3%) too high at 6 Sept 2026, 11:00 CEST (UTC+02:00).
- Across 47 European bidding zones ranked by average error over their own latest 30 day windows, Netherlands came 46 (1 is the smallest error).
- On average the forecast differed from reported demand by 1,874 MW, against average demand of 9,153 MW.
- The forecast was above reported demand in 91% of compared hours.
Forecast Error at a Glance
673 hours from 23 August to 20 September 2026Average error26.8%
Bias+25.2%
Hours within 5%13%
Worst miss8,217 MW
Average error is the mean absolute percentage gap between the forecast and reported demand. Bias is the signed mean (+1,703 MW per hour on average): the forecast ran high on average, an over forecast. The worst miss was 8,217 MW (281.3%) too high at 6 Sept 2026, 11:00 CEST (UTC+02:00): forecast 11,137 MW, reported 2,921 MW.
Source: ENTSO-E Transparency Platform (transparency.entsoe.eu), CC BY 4.0. Aggregated and converted by World Power Monitor; ENTSO-E does not endorse this site. (ENTSO-E Terms of Use plus CC BY 4.0 for listed data items) Data as of 2026-09-20. Accuracy is computed by World Power Monitor from the operator's hourly forecast and reported demand.
Forecast and Reported Demand, Last 7 Days
Local time, to 20 Sept 2026, 13:00 CEST (UTC+02:00)Data to 2026-09-20
| Local hour | Reported demand | Day-ahead forecast |
|---|---|---|
| 13 Sept, 14:00 | 8,280 MW | 9,502 MW |
| 13 Sept, 15:00 | 7,134 MW | 9,507 MW |
| 13 Sept, 16:00 | 7,228 MW | 9,810 MW |
| 13 Sept, 17:00 | 8,834 MW | 10,295 MW |
| 13 Sept, 18:00 | 9,862 MW | 11,081 MW |
| 13 Sept, 19:00 | 10,258 MW | 12,063 MW |
| 13 Sept, 20:00 | 10,435 MW | 12,446 MW |
| 13 Sept, 21:00 | 10,629 MW | 12,445 MW |
| 13 Sept, 22:00 | 10,671 MW | 12,152 MW |
| 13 Sept, 23:00 | 10,479 MW | 11,865 MW |
| 14 Sept, 00:00 | 10,452 MW | 10,351 MW |
| 14 Sept, 01:00 | 10,463 MW | 10,260 MW |
| 14 Sept, 02:00 | 10,389 MW | 10,098 MW |
| 14 Sept, 03:00 | 10,232 MW | 10,171 MW |
| 14 Sept, 04:00 | 10,416 MW | 10,126 MW |
| 14 Sept, 05:00 | 10,276 MW | 10,253 MW |
| 14 Sept, 06:00 | 10,052 MW | 10,715 MW |
| 14 Sept, 07:00 | 10,590 MW | 11,351 MW |
| 14 Sept, 08:00 | 10,792 MW | 11,496 MW |
| 14 Sept, 09:00 | 10,268 MW | 10,780 MW |
| 14 Sept, 10:00 | 9,078 MW | 9,733 MW |
| 14 Sept, 11:00 | 8,143 MW | 8,938 MW |
| 14 Sept, 12:00 | 7,620 MW | 8,579 MW |
| 14 Sept, 13:00 | 7,371 MW | 8,411 MW |
| 14 Sept, 14:00 | 7,385 MW | 8,560 MW |
| 14 Sept, 15:00 | 7,715 MW | 8,942 MW |
| 14 Sept, 16:00 | 9,022 MW | 9,618 MW |
| 14 Sept, 17:00 | 10,298 MW | 11,172 MW |
| 14 Sept, 18:00 | 10,890 MW | 11,968 MW |
| 14 Sept, 19:00 | 11,439 MW | 12,325 MW |
| 14 Sept, 20:00 | 11,681 MW | 12,950 MW |
| 14 Sept, 21:00 | 11,595 MW | 13,063 MW |
| 14 Sept, 22:00 | 11,211 MW | 12,667 MW |
| 14 Sept, 23:00 | 11,025 MW | 12,396 MW |
| 15 Sept, 00:00 | 10,872 MW | 11,875 MW |
| 15 Sept, 01:00 | 10,395 MW | 11,395 MW |
| 15 Sept, 02:00 | 10,326 MW | 11,126 MW |
| 15 Sept, 03:00 | 10,056 MW | 10,975 MW |
| 15 Sept, 04:00 | 9,956 MW | 10,851 MW |
| 15 Sept, 05:00 | 9,969 MW | 10,951 MW |
| 15 Sept, 06:00 | 9,933 MW | 11,351 MW |
| 15 Sept, 07:00 | 10,421 MW | 12,122 MW |
| 15 Sept, 08:00 | 10,401 MW | 12,531 MW |
| 15 Sept, 09:00 | 9,168 MW | 12,486 MW |
| 15 Sept, 10:00 | 7,176 MW | 11,959 MW |
| 15 Sept, 11:00 | 5,934 MW | 11,582 MW |
| 15 Sept, 12:00 | 4,607 MW | 11,021 MW |
| 15 Sept, 13:00 | 4,437 MW | 10,480 MW |
| 15 Sept, 14:00 | 5,265 MW | 10,255 MW |
| 15 Sept, 15:00 | 7,015 MW | 10,116 MW |
| 15 Sept, 16:00 | 8,846 MW | 10,839 MW |
| 15 Sept, 17:00 | 10,562 MW | 11,968 MW |
| 15 Sept, 18:00 | 10,880 MW | 12,354 MW |
| 15 Sept, 19:00 | 11,515 MW | 12,529 MW |
| 15 Sept, 20:00 | 11,400 MW | 12,804 MW |
| 15 Sept, 21:00 | 11,532 MW | 12,797 MW |
| 15 Sept, 22:00 | 11,860 MW | 12,317 MW |
| 15 Sept, 23:00 | 11,754 MW | 12,022 MW |
| 16 Sept, 00:00 | 11,496 MW | 11,829 MW |
| 16 Sept, 01:00 | 11,210 MW | 11,270 MW |
| 16 Sept, 02:00 | 11,044 MW | 10,930 MW |
| 16 Sept, 03:00 | 11,060 MW | 10,541 MW |
| 16 Sept, 04:00 | 10,722 MW | 10,500 MW |
| 16 Sept, 05:00 | 10,396 MW | 10,532 MW |
| 16 Sept, 06:00 | 9,920 MW | 10,837 MW |
| 16 Sept, 07:00 | 10,716 MW | 11,569 MW |
| 16 Sept, 08:00 | 10,599 MW | 11,794 MW |
| 16 Sept, 09:00 | 9,378 MW | 10,964 MW |
| 16 Sept, 10:00 | 8,176 MW | 10,040 MW |
| 16 Sept, 11:00 | 7,224 MW | 9,819 MW |
| 16 Sept, 12:00 | 6,790 MW | 9,924 MW |
| 16 Sept, 13:00 | 6,890 MW | 10,146 MW |
| 16 Sept, 14:00 | 7,360 MW | 9,887 MW |
| 16 Sept, 15:00 | 7,403 MW | 9,944 MW |
| 16 Sept, 16:00 | 8,046 MW | 10,393 MW |
| 16 Sept, 17:00 | 9,209 MW | 11,769 MW |
| 16 Sept, 18:00 | 10,151 MW | 12,374 MW |
| 16 Sept, 19:00 | 10,836 MW | 12,782 MW |
| 16 Sept, 20:00 | 11,027 MW | 13,061 MW |
| 16 Sept, 21:00 | 11,262 MW | 12,938 MW |
| 16 Sept, 22:00 | 11,353 MW | 12,241 MW |
| 16 Sept, 23:00 | 11,286 MW | 11,807 MW |
| 17 Sept, 00:00 | 10,734 MW | 11,355 MW |
| 17 Sept, 01:00 | 10,516 MW | 10,772 MW |
| 17 Sept, 02:00 | 10,332 MW | 10,556 MW |
| 17 Sept, 03:00 | 9,965 MW | 10,387 MW |
| 17 Sept, 04:00 | 9,743 MW | 10,239 MW |
| 17 Sept, 05:00 | 9,881 MW | 10,385 MW |
| 17 Sept, 06:00 | 9,523 MW | 10,838 MW |
| 17 Sept, 07:00 | 10,101 MW | 11,548 MW |
| 17 Sept, 08:00 | 10,959 MW | 12,003 MW |
| 17 Sept, 09:00 | 10,770 MW | 11,711 MW |
| 17 Sept, 10:00 | 9,758 MW | 10,931 MW |
| 17 Sept, 11:00 | 8,463 MW | 10,158 MW |
| 17 Sept, 12:00 | 8,536 MW | 9,480 MW |
| 17 Sept, 13:00 | 9,758 MW | 9,137 MW |
| 17 Sept, 14:00 | 10,940 MW | 9,172 MW |
| 17 Sept, 15:00 | 11,100 MW | 9,580 MW |
| 17 Sept, 16:00 | 11,270 MW | 10,168 MW |
| 17 Sept, 17:00 | 11,618 MW | 10,985 MW |
| 17 Sept, 18:00 | 11,790 MW | 11,797 MW |
| 17 Sept, 19:00 | 11,488 MW | 12,386 MW |
| 17 Sept, 20:00 | 11,239 MW | 12,639 MW |
| 17 Sept, 21:00 | 11,571 MW | 12,724 MW |
| 17 Sept, 22:00 | 11,509 MW | 12,158 MW |
| 17 Sept, 23:00 | 11,568 MW | 11,590 MW |
| 18 Sept, 00:00 | 11,422 MW | 11,109 MW |
| 18 Sept, 01:00 | 10,892 MW | 10,925 MW |
| 18 Sept, 02:00 | 10,557 MW | 10,602 MW |
| 18 Sept, 03:00 | 9,998 MW | 10,419 MW |
| 18 Sept, 04:00 | 9,997 MW | 10,435 MW |
| 18 Sept, 05:00 | 10,004 MW | 10,489 MW |
| 18 Sept, 06:00 | 9,987 MW | 10,988 MW |
| 18 Sept, 07:00 | 10,441 MW | 11,597 MW |
| 18 Sept, 08:00 | 10,609 MW | 12,072 MW |
| 18 Sept, 09:00 | 9,585 MW | 12,191 MW |
| 18 Sept, 10:00 | 7,912 MW | 12,044 MW |
| 18 Sept, 11:00 | 6,549 MW | 12,367 MW |
| 18 Sept, 12:00 | 6,626 MW | 12,141 MW |
| 18 Sept, 13:00 | 6,590 MW | 12,228 MW |
| 18 Sept, 14:00 | 7,037 MW | 12,133 MW |
| 18 Sept, 15:00 | 7,719 MW | 12,028 MW |
| 18 Sept, 16:00 | 7,962 MW | 11,969 MW |
| 18 Sept, 17:00 | 8,717 MW | 12,223 MW |
| 18 Sept, 18:00 | 9,945 MW | 12,431 MW |
| 18 Sept, 19:00 | 10,406 MW | 12,766 MW |
| 18 Sept, 20:00 | 10,138 MW | 13,067 MW |
| 18 Sept, 21:00 | 10,079 MW | 12,921 MW |
| 18 Sept, 22:00 | 10,000 MW | 12,552 MW |
| 18 Sept, 23:00 | 9,773 MW | 12,087 MW |
| 19 Sept, 00:00 | 9,743 MW | 11,669 MW |
| 19 Sept, 01:00 | 9,573 MW | 10,948 MW |
| 19 Sept, 02:00 | 9,305 MW | 10,470 MW |
| 19 Sept, 03:00 | 9,301 MW | 10,358 MW |
| 19 Sept, 04:00 | 9,386 MW | 10,472 MW |
| 19 Sept, 05:00 | 9,389 MW | 10,417 MW |
| 19 Sept, 06:00 | 9,392 MW | 10,316 MW |
| 19 Sept, 07:00 | 9,554 MW | 10,403 MW |
| 19 Sept, 08:00 | 9,709 MW | 10,193 MW |
| 19 Sept, 09:00 | 9,636 MW | 9,574 MW |
| 19 Sept, 10:00 | 8,810 MW | 8,941 MW |
| 19 Sept, 11:00 | 8,426 MW | 8,522 MW |
| 19 Sept, 12:00 | 8,062 MW | 8,257 MW |
| 19 Sept, 13:00 | 7,976 MW | 8,319 MW |
| 19 Sept, 14:00 | 8,147 MW | 8,107 MW |
| 19 Sept, 15:00 | 8,277 MW | 7,768 MW |
| 19 Sept, 16:00 | 8,888 MW | 8,271 MW |
| 19 Sept, 17:00 | 9,798 MW | 9,429 MW |
| 19 Sept, 18:00 | 10,290 MW | 10,417 MW |
| 19 Sept, 19:00 | 10,223 MW | 11,282 MW |
| 19 Sept, 20:00 | 10,267 MW | 11,673 MW |
| 19 Sept, 21:00 | 10,028 MW | 11,727 MW |
| 19 Sept, 22:00 | 9,920 MW | 11,377 MW |
| 19 Sept, 23:00 | 9,946 MW | 10,946 MW |
| 20 Sept, 00:00 | 9,883 MW | 11,671 MW |
| 20 Sept, 01:00 | 9,764 MW | 11,387 MW |
| 20 Sept, 02:00 | 9,840 MW | 10,981 MW |
| 20 Sept, 03:00 | 9,978 MW | 10,623 MW |
| 20 Sept, 04:00 | 9,747 MW | 10,303 MW |
| 20 Sept, 05:00 | 9,506 MW | 10,222 MW |
| 20 Sept, 06:00 | 9,392 MW | 10,158 MW |
| 20 Sept, 07:00 | 9,723 MW | 10,347 MW |
| 20 Sept, 08:00 | 9,816 MW | 10,785 MW |
| 20 Sept, 09:00 | 9,399 MW | 11,298 MW |
| 20 Sept, 10:00 | 8,501 MW | 11,581 MW |
| 20 Sept, 11:00 | 7,388 MW | 11,933 MW |
| 20 Sept, 12:00 | 6,165 MW | 12,185 MW |
| 20 Sept, 13:00 | 5,494 MW | 12,050 MW |
Assumptions
- Only hours with both a forecast and a positive demand reading count (673 of 686 hours in the window). Missing and zero values, and readings under 30% or over 3 times the grid's own median for the window, are treated as reporting faults and left out.
- Error is (forecast minus reported demand) divided by reported demand; average error uses absolute values so high and low misses do not cancel. Bias keeps the sign and does cancel.
- Reported demand is preliminary and may be revised. A 30 day window is a short sample and one heat wave or holiday can move these figures.
- European figures are for the ENTSO-E bidding zone named on this page. US and European grids are ranked separately.