GVL Demand Forecast Accuracy: Error, Bias and Worst Miss, 13 October to 12 November 2026

The day-ahead demand forecast for GVL was off by 7.7% on average (mean absolute percentage error) over 491 hours from 13 October to 12 November 2026, and 28% of hours landed within 5% of the reading. Its bias was -6.8%: it ran low on average, an under forecast. The largest miss was 72 MW (30.0%) too low at 17 Oct 2026, 00:00 EDT (UTC-04:00). Dates and times are local (America/New_York).

This grid has 491 compared hours out of the 720 in its 30 day window, because the forecast or the demand reading is missing for the rest. Treat the figures as a shorter sample.

Key Facts

The day-ahead demand forecast for GVL was off by 7.7% on average (mean absolute percentage error) over 491 hours from 13 October to 12 November 2026, and 28% of hours landed within 5% of the reading. Its bias was -6.8%: it ran low on average, an under forecast. The largest miss was 72 MW (30.0%) too low at 17 Oct 2026, 00:00 EDT (UTC-04:00).
Across 53 US grids ranked by average error over their own latest 30 day windows, GVL came 39 (1 is the smallest error).
On average the forecast differed from reported demand by 17 MW, against average demand of 208 MW.
The forecast was above reported demand in 12% of compared hours.

Forecast Error at a Glance

491 hours from 13 October to 12 November 2026

Average error7.7%

Bias-6.8%

Hours within 5%28%

Worst miss72 MW

Average error is the mean absolute percentage gap between the forecast and reported demand. Bias is the signed mean (-15 MW per hour on average): the forecast ran low on average, an under forecast. The worst miss was 72 MW (30.0%) too low at 17 Oct 2026, 00:00 EDT (UTC-04:00): forecast 168 MW, reported 240 MW.

Source: U.S. Energy Information Administration (EIA). (US Government work, public domain) Data as of 2026-11-12. 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 12 Nov 2026, 07:00 EST (UTC-05:00)

Hourly reported demand and the day-ahead forecast for GVL over the last 7 days of the window, to 12 Nov 2026, 07:00 EST (UTC-05:00). Gaps are hours with a missing, zero or implausible report.

Data to 2026-11-12

Show the data table (168 rows)

Local hour	Reported demand	Day-ahead forecast
5 Nov, 08:00	n/a	n/a
5 Nov, 09:00	n/a	n/a
5 Nov, 10:00	n/a	n/a
5 Nov, 11:00	n/a	n/a
5 Nov, 12:00	n/a	n/a
5 Nov, 13:00	n/a	n/a
5 Nov, 14:00	n/a	n/a
5 Nov, 15:00	n/a	n/a
5 Nov, 16:00	n/a	n/a
5 Nov, 17:00	n/a	n/a
5 Nov, 18:00	n/a	n/a
5 Nov, 19:00	n/a	n/a
5 Nov, 20:00	n/a	n/a
5 Nov, 21:00	n/a	n/a
5 Nov, 22:00	n/a	n/a
5 Nov, 23:00	n/a	n/a
6 Nov, 00:00	216 MW	n/a
6 Nov, 01:00	198 MW	n/a
6 Nov, 02:00	185 MW	n/a
6 Nov, 03:00	176 MW	n/a
6 Nov, 04:00	173 MW	n/a
6 Nov, 05:00	180 MW	n/a
6 Nov, 06:00	193 MW	n/a
6 Nov, 07:00	204 MW	n/a
6 Nov, 08:00	219 MW	n/a
6 Nov, 09:00	235 MW	n/a
6 Nov, 10:00	250 MW	n/a
6 Nov, 11:00	267 MW	n/a
6 Nov, 12:00	284 MW	n/a
6 Nov, 13:00	301 MW	n/a
6 Nov, 14:00	301 MW	n/a
6 Nov, 15:00	n/a	n/a
6 Nov, 16:00	302 MW	n/a
6 Nov, 17:00	296 MW	n/a
6 Nov, 18:00	293 MW	n/a
6 Nov, 19:00	281 MW	n/a
6 Nov, 20:00	268 MW	n/a
6 Nov, 21:00	253 MW	n/a
6 Nov, 22:00	235 MW	n/a
6 Nov, 23:00	217 MW	n/a
7 Nov, 00:00	201 MW	176 MW
7 Nov, 01:00	189 MW	164 MW
7 Nov, 02:00	179 MW	156 MW
7 Nov, 03:00	171 MW	151 MW
7 Nov, 04:00	164 MW	149 MW
7 Nov, 05:00	162 MW	150 MW
7 Nov, 06:00	164 MW	154 MW
7 Nov, 07:00	169 MW	162 MW
7 Nov, 08:00	182 MW	177 MW
7 Nov, 09:00	193 MW	192 MW
7 Nov, 10:00	207 MW	209 MW
7 Nov, 11:00	222 MW	225 MW
7 Nov, 12:00	238 MW	238 MW
7 Nov, 13:00	252 MW	235 MW
7 Nov, 14:00	263 MW	244 MW
7 Nov, 15:00	268 MW	244 MW
7 Nov, 16:00	262 MW	245 MW
7 Nov, 17:00	249 MW	243 MW
7 Nov, 18:00	240 MW	242 MW
7 Nov, 19:00	225 MW	232 MW
7 Nov, 20:00	212 MW	222 MW
7 Nov, 21:00	202 MW	212 MW
7 Nov, 22:00	190 MW	199 MW
7 Nov, 23:00	183 MW	186 MW
8 Nov, 00:00	172 MW	157 MW
8 Nov, 01:00	159 MW	148 MW
8 Nov, 02:00	149 MW	143 MW
8 Nov, 03:00	143 MW	140 MW
8 Nov, 04:00	141 MW	139 MW
8 Nov, 05:00	143 MW	141 MW
8 Nov, 06:00	147 MW	146 MW
8 Nov, 07:00	156 MW	152 MW
8 Nov, 08:00	169 MW	162 MW
8 Nov, 09:00	179 MW	168 MW
8 Nov, 10:00	190 MW	173 MW
8 Nov, 11:00	201 MW	180 MW
8 Nov, 12:00	212 MW	188 MW
8 Nov, 13:00	225 MW	196 MW
8 Nov, 14:00	238 MW	202 MW
8 Nov, 15:00	247 MW	205 MW
8 Nov, 16:00	251 MW	207 MW
8 Nov, 17:00	251 MW	214 MW
8 Nov, 18:00	251 MW	217 MW
8 Nov, 19:00	241 MW	212 MW
8 Nov, 20:00	230 MW	204 MW
8 Nov, 21:00	217 MW	195 MW
8 Nov, 22:00	201 MW	181 MW
8 Nov, 23:00	182 MW	167 MW
9 Nov, 00:00	167 MW	159 MW
9 Nov, 01:00	154 MW	149 MW
9 Nov, 02:00	147 MW	142 MW
9 Nov, 03:00	144 MW	138 MW
9 Nov, 04:00	146 MW	139 MW
9 Nov, 05:00	153 MW	143 MW
9 Nov, 06:00	170 MW	153 MW
9 Nov, 07:00	180 MW	161 MW
9 Nov, 08:00	186 MW	172 MW
9 Nov, 09:00	193 MW	181 MW
9 Nov, 10:00	200 MW	191 MW
9 Nov, 11:00	207 MW	202 MW
9 Nov, 12:00	218 MW	208 MW
9 Nov, 13:00	229 MW	213 MW
9 Nov, 14:00	238 MW	219 MW
9 Nov, 15:00	246 MW	222 MW
9 Nov, 16:00	251 MW	223 MW
9 Nov, 17:00	250 MW	226 MW
9 Nov, 18:00	252 MW	226 MW
9 Nov, 19:00	245 MW	221 MW
9 Nov, 20:00	232 MW	213 MW
9 Nov, 21:00	216 MW	204 MW
9 Nov, 22:00	198 MW	191 MW
9 Nov, 23:00	180 MW	179 MW
10 Nov, 00:00	166 MW	150 MW
10 Nov, 01:00	154 MW	142 MW
10 Nov, 02:00	147 MW	137 MW
10 Nov, 03:00	143 MW	135 MW
10 Nov, 04:00	144 MW	136 MW
10 Nov, 05:00	153 MW	142 MW
10 Nov, 06:00	170 MW	153 MW
10 Nov, 07:00	180 MW	162 MW
10 Nov, 08:00	187 MW	170 MW
10 Nov, 09:00	192 MW	177 MW
10 Nov, 10:00	198 MW	183 MW
10 Nov, 11:00	207 MW	191 MW
10 Nov, 12:00	216 MW	197 MW
10 Nov, 13:00	228 MW	203 MW
10 Nov, 14:00	241 MW	209 MW
10 Nov, 15:00	248 MW	214 MW
10 Nov, 16:00	250 MW	215 MW
10 Nov, 17:00	255 MW	215 MW
10 Nov, 18:00	258 MW	216 MW
10 Nov, 19:00	249 MW	209 MW
10 Nov, 20:00	235 MW	201 MW
10 Nov, 21:00	223 MW	193 MW
10 Nov, 22:00	207 MW	181 MW
10 Nov, 23:00	191 MW	168 MW
11 Nov, 00:00	177 MW	160 MW
11 Nov, 01:00	166 MW	149 MW
11 Nov, 02:00	158 MW	141 MW
11 Nov, 03:00	152 MW	137 MW
11 Nov, 04:00	152 MW	137 MW
11 Nov, 05:00	156 MW	144 MW
11 Nov, 06:00	167 MW	159 MW
11 Nov, 07:00	175 MW	170 MW
11 Nov, 08:00	186 MW	175 MW
11 Nov, 09:00	196 MW	181 MW
11 Nov, 10:00	210 MW	185 MW
11 Nov, 11:00	225 MW	191 MW
11 Nov, 12:00	240 MW	197 MW
11 Nov, 13:00	256 MW	200 MW
11 Nov, 14:00	257 MW	210 MW
11 Nov, 15:00	255 MW	220 MW
11 Nov, 16:00	250 MW	227 MW
11 Nov, 17:00	251 MW	232 MW
11 Nov, 18:00	251 MW	231 MW
11 Nov, 19:00	243 MW	233 MW
11 Nov, 20:00	232 MW	224 MW
11 Nov, 21:00	218 MW	211 MW
11 Nov, 22:00	200 MW	193 MW
11 Nov, 23:00	182 MW	175 MW
12 Nov, 00:00	167 MW	154 MW
12 Nov, 01:00	156 MW	143 MW
12 Nov, 02:00	147 MW	135 MW
12 Nov, 03:00	145 MW	131 MW
12 Nov, 04:00	146 MW	132 MW
12 Nov, 05:00	155 MW	137 MW
12 Nov, 06:00	172 MW	150 MW
12 Nov, 07:00	182 MW	160 MW

Assumptions

Only hours with both a forecast and a positive demand reading count (491 of 720 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.
US figures are for the EIA balancing authority or region named on this page. US and European grids are ranked separately.

Cite this page

APA 7

World Power Monitor. (2026). GVL Demand Forecast Accuracy: Error, Bias and Worst Miss. https://worldpowermonitor.com/forecast-accuracy/gvl/

Plain text

World Power Monitor. GVL Demand Forecast Accuracy: Error, Bias and Worst Miss. Data as of 2026-11-12. Data from U.S. Energy Information Administration. https://worldpowermonitor.com/forecast-accuracy/gvl/

BibTeX

@misc{wpm_forecast_accuracy_gvl_2026,
  title = {{GVL Demand Forecast Accuracy: Error, Bias and Worst Miss}},
  author = {{World Power Monitor}},
  year = {2026},
  note = {Data as of 2026-11-12. Data from U.S. Energy Information Administration.},
  url = {https://worldpowermonitor.com/forecast-accuracy/gvl/}
}

Permalink: https://worldpowermonitor.com/forecast-accuracy/gvl/

The Copy buttons add today's date as the access date.

GVL Demand Forecast Accuracy: Error, Bias and Worst Miss, 13 October to 12 November 2026

Key Facts

Forecast Error at a Glance

Forecast and Reported Demand, Last 7 Days

Assumptions

Related