Estonia Demand Forecast Accuracy: Error, Bias and Worst Miss, 23 August to 20 September 2026
The day-ahead demand forecast for Estonia was off by 13.4% on average (mean absolute percentage error) over 685 hours from 23 August to 20 September 2026, and 31% of hours landed within 5% of the reading. Its bias was +10.5%: it ran high on average, an over forecast. The largest miss was 472 MW (103.7%) too high at 12 Sept 2026, 11:00 EEST (UTC+03:00). Dates and times are local (Europe/Tallinn).
Key Facts
- The day-ahead demand forecast for Estonia was off by 13.4% on average (mean absolute percentage error) over 685 hours from 23 August to 20 September 2026, and 31% of hours landed within 5% of the reading. Its bias was +10.5%: it ran high on average, an over forecast. The largest miss was 472 MW (103.7%) too high at 12 Sept 2026, 11:00 EEST (UTC+03:00).
- Across 47 European bidding zones ranked by average error over their own latest 30 day windows, Estonia came 44 (1 is the smallest error).
- On average the forecast differed from reported demand by 99 MW, against average demand of 783 MW.
- The forecast was above reported demand in 74% of compared hours.
Forecast Error at a Glance
685 hours from 23 August to 20 September 2026Average error13.4%
Bias+10.5%
Hours within 5%31%
Worst miss472 MW
Average error is the mean absolute percentage gap between the forecast and reported demand. Bias is the signed mean (+73 MW per hour on average): the forecast ran high on average, an over forecast. The worst miss was 472 MW (103.7%) too high at 12 Sept 2026, 11:00 EEST (UTC+03:00): forecast 926 MW, reported 455 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, 15:00 EEST (UTC+03:00)Data to 2026-09-20
| Local hour | Reported demand | Day-ahead forecast |
|---|---|---|
| 13 Sept, 16:00 | 775 MW | 950 MW |
| 13 Sept, 17:00 | 743 MW | 883 MW |
| 13 Sept, 18:00 | 716 MW | 861 MW |
| 13 Sept, 19:00 | 739 MW | 858 MW |
| 13 Sept, 20:00 | 705 MW | 872 MW |
| 13 Sept, 21:00 | 700 MW | 875 MW |
| 13 Sept, 22:00 | 697 MW | 825 MW |
| 13 Sept, 23:00 | 661 MW | 766 MW |
| 14 Sept, 00:00 | 639 MW | 742 MW |
| 14 Sept, 01:00 | 715 MW | 735 MW |
| 14 Sept, 02:00 | 703 MW | 774 MW |
| 14 Sept, 03:00 | 699 MW | 750 MW |
| 14 Sept, 04:00 | 695 MW | 712 MW |
| 14 Sept, 05:00 | 723 MW | 734 MW |
| 14 Sept, 06:00 | 737 MW | 803 MW |
| 14 Sept, 07:00 | 848 MW | 910 MW |
| 14 Sept, 08:00 | 882 MW | 964 MW |
| 14 Sept, 09:00 | 1,010 MW | 968 MW |
| 14 Sept, 10:00 | 983 MW | 959 MW |
| 14 Sept, 11:00 | 983 MW | 952 MW |
| 14 Sept, 12:00 | 924 MW | 944 MW |
| 14 Sept, 13:00 | 828 MW | 941 MW |
| 14 Sept, 14:00 | 740 MW | 998 MW |
| 14 Sept, 15:00 | 816 MW | 957 MW |
| 14 Sept, 16:00 | 786 MW | 917 MW |
| 14 Sept, 17:00 | 768 MW | 924 MW |
| 14 Sept, 18:00 | 814 MW | 914 MW |
| 14 Sept, 19:00 | 759 MW | 901 MW |
| 14 Sept, 20:00 | 803 MW | 908 MW |
| 14 Sept, 21:00 | 761 MW | 887 MW |
| 14 Sept, 22:00 | 824 MW | 828 MW |
| 14 Sept, 23:00 | 778 MW | 779 MW |
| 15 Sept, 00:00 | 724 MW | 741 MW |
| 15 Sept, 01:00 | 685 MW | 740 MW |
| 15 Sept, 02:00 | 707 MW | 745 MW |
| 15 Sept, 03:00 | 718 MW | 777 MW |
| 15 Sept, 04:00 | 646 MW | 728 MW |
| 15 Sept, 05:00 | 784 MW | 726 MW |
| 15 Sept, 06:00 | 760 MW | 803 MW |
| 15 Sept, 07:00 | 791 MW | 890 MW |
| 15 Sept, 08:00 | 863 MW | 955 MW |
| 15 Sept, 09:00 | 967 MW | 975 MW |
| 15 Sept, 10:00 | 779 MW | 966 MW |
| 15 Sept, 11:00 | 685 MW | 950 MW |
| 15 Sept, 12:00 | 591 MW | 943 MW |
| 15 Sept, 13:00 | 699 MW | 984 MW |
| 15 Sept, 14:00 | 793 MW | 1,013 MW |
| 15 Sept, 15:00 | 871 MW | 998 MW |
| 15 Sept, 16:00 | 847 MW | 895 MW |
| 15 Sept, 17:00 | 754 MW | 907 MW |
| 15 Sept, 18:00 | 796 MW | 917 MW |
| 15 Sept, 19:00 | 784 MW | 903 MW |
| 15 Sept, 20:00 | 786 MW | 911 MW |
| 15 Sept, 21:00 | 801 MW | 892 MW |
| 15 Sept, 22:00 | 790 MW | 842 MW |
| 15 Sept, 23:00 | 771 MW | 778 MW |
| 16 Sept, 00:00 | 802 MW | 740 MW |
| 16 Sept, 01:00 | 802 MW | 724 MW |
| 16 Sept, 02:00 | 751 MW | 728 MW |
| 16 Sept, 03:00 | 706 MW | 730 MW |
| 16 Sept, 04:00 | 661 MW | 729 MW |
| 16 Sept, 05:00 | 621 MW | 758 MW |
| 16 Sept, 06:00 | 761 MW | 808 MW |
| 16 Sept, 07:00 | 874 MW | 886 MW |
| 16 Sept, 08:00 | 884 MW | 959 MW |
| 16 Sept, 09:00 | 754 MW | 994 MW |
| 16 Sept, 10:00 | 784 MW | 973 MW |
| 16 Sept, 11:00 | 839 MW | 952 MW |
| 16 Sept, 12:00 | 877 MW | 953 MW |
| 16 Sept, 13:00 | 811 MW | 964 MW |
| 16 Sept, 14:00 | 727 MW | 1,040 MW |
| 16 Sept, 15:00 | 808 MW | 1,027 MW |
| 16 Sept, 16:00 | 808 MW | 987 MW |
| 16 Sept, 17:00 | 886 MW | 957 MW |
| 16 Sept, 18:00 | 793 MW | 961 MW |
| 16 Sept, 19:00 | 817 MW | 970 MW |
| 16 Sept, 20:00 | 876 MW | 933 MW |
| 16 Sept, 21:00 | 807 MW | 929 MW |
| 16 Sept, 22:00 | 805 MW | 895 MW |
| 16 Sept, 23:00 | 807 MW | 821 MW |
| 17 Sept, 00:00 | 762 MW | 769 MW |
| 17 Sept, 01:00 | 757 MW | 774 MW |
| 17 Sept, 02:00 | 726 MW | 767 MW |
| 17 Sept, 03:00 | 729 MW | 764 MW |
| 17 Sept, 04:00 | 770 MW | 829 MW |
| 17 Sept, 05:00 | 767 MW | 785 MW |
| 17 Sept, 06:00 | 836 MW | 862 MW |
| 17 Sept, 07:00 | 823 MW | 940 MW |
| 17 Sept, 08:00 | 830 MW | 994 MW |
| 17 Sept, 09:00 | 812 MW | 1,005 MW |
| 17 Sept, 10:00 | 823 MW | 1,026 MW |
| 17 Sept, 11:00 | 833 MW | 1,073 MW |
| 17 Sept, 12:00 | 767 MW | 1,075 MW |
| 17 Sept, 13:00 | 761 MW | 1,060 MW |
| 17 Sept, 14:00 | 960 MW | 1,124 MW |
| 17 Sept, 15:00 | 1,042 MW | 1,081 MW |
| 17 Sept, 16:00 | 832 MW | 1,005 MW |
| 17 Sept, 17:00 | 922 MW | 975 MW |
| 17 Sept, 18:00 | 834 MW | 943 MW |
| 17 Sept, 19:00 | 812 MW | 958 MW |
| 17 Sept, 20:00 | 780 MW | 963 MW |
| 17 Sept, 21:00 | 849 MW | 927 MW |
| 17 Sept, 22:00 | 814 MW | 866 MW |
| 17 Sept, 23:00 | 778 MW | 806 MW |
| 18 Sept, 00:00 | 738 MW | 767 MW |
| 18 Sept, 01:00 | 696 MW | 759 MW |
| 18 Sept, 02:00 | 708 MW | 728 MW |
| 18 Sept, 03:00 | 661 MW | 721 MW |
| 18 Sept, 04:00 | 638 MW | 776 MW |
| 18 Sept, 05:00 | 672 MW | 783 MW |
| 18 Sept, 06:00 | 800 MW | 841 MW |
| 18 Sept, 07:00 | 791 MW | 893 MW |
| 18 Sept, 08:00 | 743 MW | 953 MW |
| 18 Sept, 09:00 | 863 MW | 981 MW |
| 18 Sept, 10:00 | 851 MW | 956 MW |
| 18 Sept, 11:00 | 980 MW | 947 MW |
| 18 Sept, 12:00 | 1,099 MW | 995 MW |
| 18 Sept, 13:00 | 928 MW | 1,038 MW |
| 18 Sept, 14:00 | 938 MW | 1,077 MW |
| 18 Sept, 15:00 | n/a | 1,033 MW |
| 18 Sept, 16:00 | n/a | 942 MW |
| 18 Sept, 17:00 | 987 MW | 958 MW |
| 18 Sept, 18:00 | 898 MW | 941 MW |
| 18 Sept, 19:00 | 856 MW | 931 MW |
| 18 Sept, 20:00 | 893 MW | 926 MW |
| 18 Sept, 21:00 | 874 MW | 896 MW |
| 18 Sept, 22:00 | 825 MW | 848 MW |
| 18 Sept, 23:00 | 760 MW | 794 MW |
| 19 Sept, 00:00 | 689 MW | 764 MW |
| 19 Sept, 01:00 | 686 MW | 704 MW |
| 19 Sept, 02:00 | 650 MW | 682 MW |
| 19 Sept, 03:00 | 620 MW | 671 MW |
| 19 Sept, 04:00 | 626 MW | 665 MW |
| 19 Sept, 05:00 | 634 MW | 658 MW |
| 19 Sept, 06:00 | 665 MW | 654 MW |
| 19 Sept, 07:00 | 672 MW | 686 MW |
| 19 Sept, 08:00 | 722 MW | 744 MW |
| 19 Sept, 09:00 | 795 MW | 763 MW |
| 19 Sept, 10:00 | 798 MW | 776 MW |
| 19 Sept, 11:00 | 819 MW | 789 MW |
| 19 Sept, 12:00 | 843 MW | 847 MW |
| 19 Sept, 13:00 | 723 MW | 869 MW |
| 19 Sept, 14:00 | 722 MW | 832 MW |
| 19 Sept, 15:00 | 736 MW | 828 MW |
| 19 Sept, 16:00 | 780 MW | 806 MW |
| 19 Sept, 17:00 | 799 MW | 812 MW |
| 19 Sept, 18:00 | 813 MW | 806 MW |
| 19 Sept, 19:00 | 831 MW | 814 MW |
| 19 Sept, 20:00 | 848 MW | 830 MW |
| 19 Sept, 21:00 | 809 MW | 836 MW |
| 19 Sept, 22:00 | 767 MW | 795 MW |
| 19 Sept, 23:00 | 709 MW | 752 MW |
| 20 Sept, 00:00 | 653 MW | 693 MW |
| 20 Sept, 01:00 | 667 MW | 688 MW |
| 20 Sept, 02:00 | 652 MW | 685 MW |
| 20 Sept, 03:00 | 642 MW | 695 MW |
| 20 Sept, 04:00 | 639 MW | 689 MW |
| 20 Sept, 05:00 | 645 MW | 690 MW |
| 20 Sept, 06:00 | 662 MW | 689 MW |
| 20 Sept, 07:00 | 691 MW | 719 MW |
| 20 Sept, 08:00 | 771 MW | 768 MW |
| 20 Sept, 09:00 | 872 MW | 815 MW |
| 20 Sept, 10:00 | 922 MW | 886 MW |
| 20 Sept, 11:00 | 929 MW | 900 MW |
| 20 Sept, 12:00 | 741 MW | 914 MW |
| 20 Sept, 13:00 | 732 MW | 921 MW |
| 20 Sept, 14:00 | 704 MW | 917 MW |
| 20 Sept, 15:00 | 744 MW | 884 MW |
Assumptions
- Only hours with both a forecast and a positive demand reading count (685 of 688 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.