Montenegro Demand Forecast Accuracy: Error, Bias and Worst Miss, 23 August to 19 September 2026
The day-ahead demand forecast for Montenegro was off by 9.1% on average (mean absolute percentage error) over 672 hours from 23 August to 19 September 2026, and 45% of hours landed within 5% of the reading. Its bias was +3.9%: it ran high on average, an over forecast. The largest miss was 211 MW (67.1%) too high at 4 Sept 2026, 21:00 CEST (UTC+02:00). Dates and times are local (Europe/Podgorica).
Key Facts
- The day-ahead demand forecast for Montenegro was off by 9.1% on average (mean absolute percentage error) over 672 hours from 23 August to 19 September 2026, and 45% of hours landed within 5% of the reading. Its bias was +3.9%: it ran high on average, an over forecast. The largest miss was 211 MW (67.1%) too high at 4 Sept 2026, 21:00 CEST (UTC+02:00).
- Across 47 European bidding zones ranked by average error over their own latest 30 day windows, Montenegro came 41 (1 is the smallest error).
- On average the forecast differed from reported demand by 36 MW, against average demand of 417 MW.
- The forecast was above reported demand in 65% of compared hours.
Forecast Error at a Glance
672 hours from 23 August to 19 September 2026Average error9.1%
Bias+3.9%
Hours within 5%45%
Worst miss211 MW
Average error is the mean absolute percentage gap between the forecast and reported demand. Bias is the signed mean (+11 MW per hour on average): the forecast ran high on average, an over forecast. The worst miss was 211 MW (67.1%) too high at 4 Sept 2026, 21:00 CEST (UTC+02:00): forecast 526 MW, reported 315 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 2026-09-19. 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 19 Sept 2026, 23:00 CEST (UTC+02:00)Data to 2026-09-19
| Local hour | Reported demand | Day-ahead forecast |
|---|---|---|
| 13 Sept, 00:00 | 341 MW | 337 MW |
| 13 Sept, 01:00 | 304 MW | 297 MW |
| 13 Sept, 02:00 | 305 MW | 274 MW |
| 13 Sept, 03:00 | 304 MW | 267 MW |
| 13 Sept, 04:00 | 305 MW | 258 MW |
| 13 Sept, 05:00 | 282 MW | 262 MW |
| 13 Sept, 06:00 | 313 MW | 274 MW |
| 13 Sept, 07:00 | 395 MW | 305 MW |
| 13 Sept, 08:00 | 452 MW | 339 MW |
| 13 Sept, 09:00 | 485 MW | 367 MW |
| 13 Sept, 10:00 | 463 MW | 381 MW |
| 13 Sept, 11:00 | 445 MW | 398 MW |
| 13 Sept, 12:00 | 451 MW | 415 MW |
| 13 Sept, 13:00 | 458 MW | 434 MW |
| 13 Sept, 14:00 | 474 MW | 448 MW |
| 13 Sept, 15:00 | 489 MW | 461 MW |
| 13 Sept, 16:00 | 454 MW | 467 MW |
| 13 Sept, 17:00 | 428 MW | 473 MW |
| 13 Sept, 18:00 | 385 MW | 483 MW |
| 13 Sept, 19:00 | 392 MW | 496 MW |
| 13 Sept, 20:00 | 389 MW | 496 MW |
| 13 Sept, 21:00 | 361 MW | 475 MW |
| 13 Sept, 22:00 | 324 MW | 435 MW |
| 13 Sept, 23:00 | 283 MW | 391 MW |
| 14 Sept, 00:00 | 290 MW | 297 MW |
| 14 Sept, 01:00 | 257 MW | 267 MW |
| 14 Sept, 02:00 | 241 MW | 253 MW |
| 14 Sept, 03:00 | 235 MW | 249 MW |
| 14 Sept, 04:00 | 228 MW | 247 MW |
| 14 Sept, 05:00 | 241 MW | 257 MW |
| 14 Sept, 06:00 | 278 MW | 284 MW |
| 14 Sept, 07:00 | 322 MW | 330 MW |
| 14 Sept, 08:00 | 341 MW | 358 MW |
| 14 Sept, 09:00 | 338 MW | 375 MW |
| 14 Sept, 10:00 | 325 MW | 382 MW |
| 14 Sept, 11:00 | 319 MW | 390 MW |
| 14 Sept, 12:00 | 322 MW | 396 MW |
| 14 Sept, 13:00 | 326 MW | 405 MW |
| 14 Sept, 14:00 | 341 MW | 412 MW |
| 14 Sept, 15:00 | 362 MW | 427 MW |
| 14 Sept, 16:00 | 386 MW | 436 MW |
| 14 Sept, 17:00 | 392 MW | 442 MW |
| 14 Sept, 18:00 | 406 MW | 448 MW |
| 14 Sept, 19:00 | 425 MW | 457 MW |
| 14 Sept, 20:00 | 424 MW | 449 MW |
| 14 Sept, 21:00 | 408 MW | 428 MW |
| 14 Sept, 22:00 | 377 MW | 394 MW |
| 14 Sept, 23:00 | 339 MW | 358 MW |
| 15 Sept, 00:00 | 297 MW | 296 MW |
| 15 Sept, 01:00 | 267 MW | 266 MW |
| 15 Sept, 02:00 | 250 MW | 249 MW |
| 15 Sept, 03:00 | 240 MW | 243 MW |
| 15 Sept, 04:00 | 239 MW | 240 MW |
| 15 Sept, 05:00 | 250 MW | 250 MW |
| 15 Sept, 06:00 | 282 MW | 282 MW |
| 15 Sept, 07:00 | 333 MW | 326 MW |
| 15 Sept, 08:00 | 361 MW | 353 MW |
| 15 Sept, 09:00 | 366 MW | 371 MW |
| 15 Sept, 10:00 | 351 MW | 376 MW |
| 15 Sept, 11:00 | 339 MW | 376 MW |
| 15 Sept, 12:00 | 333 MW | 376 MW |
| 15 Sept, 13:00 | 343 MW | 380 MW |
| 15 Sept, 14:00 | 354 MW | 386 MW |
| 15 Sept, 15:00 | 371 MW | 396 MW |
| 15 Sept, 16:00 | 377 MW | 396 MW |
| 15 Sept, 17:00 | 386 MW | 405 MW |
| 15 Sept, 18:00 | 398 MW | 412 MW |
| 15 Sept, 19:00 | 419 MW | 426 MW |
| 15 Sept, 20:00 | 413 MW | 423 MW |
| 15 Sept, 21:00 | 395 MW | 402 MW |
| 15 Sept, 22:00 | 368 MW | 374 MW |
| 15 Sept, 23:00 | 333 MW | 337 MW |
| 16 Sept, 00:00 | 289 MW | 293 MW |
| 16 Sept, 01:00 | 258 MW | 261 MW |
| 16 Sept, 02:00 | 241 MW | 245 MW |
| 16 Sept, 03:00 | 232 MW | 238 MW |
| 16 Sept, 04:00 | 228 MW | 237 MW |
| 16 Sept, 05:00 | 243 MW | 248 MW |
| 16 Sept, 06:00 | 284 MW | 285 MW |
| 16 Sept, 07:00 | 329 MW | 328 MW |
| 16 Sept, 08:00 | 345 MW | 351 MW |
| 16 Sept, 09:00 | 339 MW | 354 MW |
| 16 Sept, 10:00 | 318 MW | 356 MW |
| 16 Sept, 11:00 | 312 MW | 358 MW |
| 16 Sept, 12:00 | 316 MW | 361 MW |
| 16 Sept, 13:00 | 326 MW | 368 MW |
| 16 Sept, 14:00 | 340 MW | 374 MW |
| 16 Sept, 15:00 | 353 MW | 385 MW |
| 16 Sept, 16:00 | 375 MW | 395 MW |
| 16 Sept, 17:00 | 394 MW | 404 MW |
| 16 Sept, 18:00 | 412 MW | 410 MW |
| 16 Sept, 19:00 | 431 MW | 424 MW |
| 16 Sept, 20:00 | 425 MW | 420 MW |
| 16 Sept, 21:00 | 403 MW | 400 MW |
| 16 Sept, 22:00 | 373 MW | 368 MW |
| 16 Sept, 23:00 | 334 MW | 335 MW |
| 17 Sept, 00:00 | 292 MW | 297 MW |
| 17 Sept, 01:00 | 258 MW | 265 MW |
| 17 Sept, 02:00 | 240 MW | 246 MW |
| 17 Sept, 03:00 | 234 MW | 240 MW |
| 17 Sept, 04:00 | 229 MW | 237 MW |
| 17 Sept, 05:00 | 242 MW | 246 MW |
| 17 Sept, 06:00 | 277 MW | 287 MW |
| 17 Sept, 07:00 | 325 MW | 333 MW |
| 17 Sept, 08:00 | 341 MW | 363 MW |
| 17 Sept, 09:00 | 336 MW | 370 MW |
| 17 Sept, 10:00 | 329 MW | 365 MW |
| 17 Sept, 11:00 | 320 MW | 361 MW |
| 17 Sept, 12:00 | 328 MW | 361 MW |
| 17 Sept, 13:00 | 337 MW | 365 MW |
| 17 Sept, 14:00 | 347 MW | 374 MW |
| 17 Sept, 15:00 | 360 MW | 385 MW |
| 17 Sept, 16:00 | 376 MW | 394 MW |
| 17 Sept, 17:00 | 396 MW | 401 MW |
| 17 Sept, 18:00 | 413 MW | 412 MW |
| 17 Sept, 19:00 | 434 MW | 428 MW |
| 17 Sept, 20:00 | 427 MW | 422 MW |
| 17 Sept, 21:00 | 402 MW | 403 MW |
| 17 Sept, 22:00 | 355 MW | 377 MW |
| 17 Sept, 23:00 | 314 MW | 346 MW |
| 18 Sept, 00:00 | 300 MW | 302 MW |
| 18 Sept, 01:00 | 260 MW | 268 MW |
| 18 Sept, 02:00 | 241 MW | 252 MW |
| 18 Sept, 03:00 | 233 MW | 245 MW |
| 18 Sept, 04:00 | 231 MW | 239 MW |
| 18 Sept, 05:00 | 241 MW | 253 MW |
| 18 Sept, 06:00 | 272 MW | 287 MW |
| 18 Sept, 07:00 | 312 MW | 338 MW |
| 18 Sept, 08:00 | 327 MW | 361 MW |
| 18 Sept, 09:00 | 322 MW | 365 MW |
| 18 Sept, 10:00 | 311 MW | 359 MW |
| 18 Sept, 11:00 | 318 MW | 358 MW |
| 18 Sept, 12:00 | 322 MW | 360 MW |
| 18 Sept, 13:00 | 342 MW | 366 MW |
| 18 Sept, 14:00 | 364 MW | 373 MW |
| 18 Sept, 15:00 | 383 MW | 384 MW |
| 18 Sept, 16:00 | 392 MW | 394 MW |
| 18 Sept, 17:00 | 407 MW | 406 MW |
| 18 Sept, 18:00 | 415 MW | 418 MW |
| 18 Sept, 19:00 | 434 MW | 437 MW |
| 18 Sept, 20:00 | 420 MW | 431 MW |
| 18 Sept, 21:00 | 397 MW | 409 MW |
| 18 Sept, 22:00 | 366 MW | 377 MW |
| 18 Sept, 23:00 | 334 MW | 345 MW |
| 19 Sept, 00:00 | 299 MW | 298 MW |
| 19 Sept, 01:00 | 267 MW | 264 MW |
| 19 Sept, 02:00 | 248 MW | 246 MW |
| 19 Sept, 03:00 | 241 MW | 238 MW |
| 19 Sept, 04:00 | 234 MW | 234 MW |
| 19 Sept, 05:00 | 242 MW | 241 MW |
| 19 Sept, 06:00 | 260 MW | 266 MW |
| 19 Sept, 07:00 | 299 MW | 295 MW |
| 19 Sept, 08:00 | 332 MW | 337 MW |
| 19 Sept, 09:00 | 353 MW | 352 MW |
| 19 Sept, 10:00 | 353 MW | 355 MW |
| 19 Sept, 11:00 | 344 MW | 356 MW |
| 19 Sept, 12:00 | 352 MW | 360 MW |
| 19 Sept, 13:00 | 382 MW | 368 MW |
| 19 Sept, 14:00 | 378 MW | 377 MW |
| 19 Sept, 15:00 | 372 MW | 386 MW |
| 19 Sept, 16:00 | 374 MW | 384 MW |
| 19 Sept, 17:00 | 389 MW | 390 MW |
| 19 Sept, 18:00 | 402 MW | 403 MW |
| 19 Sept, 19:00 | 422 MW | 419 MW |
| 19 Sept, 20:00 | 410 MW | 410 MW |
| 19 Sept, 21:00 | 389 MW | 388 MW |
| 19 Sept, 22:00 | 365 MW | 361 MW |
| 19 Sept, 23:00 | 332 MW | 333 MW |
Assumptions
- Only hours with both a forecast and a positive demand reading count (672 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.