Benchmark-verified demand forecasts for U.S. power markets.

Gramm forecasts how much electricity the grid will need, sharper than each operator’s own forecast. 1.56–2.82% error across 7 U.S. markets.*

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7 U.S. gridsOASIS-compatible APIU.S. data residencySOC 2 infrastructure
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Day-ahead MAPE — 7 U.S. grids
Jan–Dec 2025
Territory
Baseline
Gramm
Δ
CAISO
4.80%
2.63%
−45.2%
ERCOT
5.10%
1.56%
−69.4%
PJM
3.90%
1.70%
−56.4%
MISO
4.30%
1.67%
−61.2%
NYISO
4.10%
1.76%
−57.1%
ISO-NE
3.70%
2.46%
−33.5%
SPP
4.60%
2.82%
−38.7%
8,760 hr / region · vs. each ISO's published DA forecastMethodology →

Illustrative savings by utility footprint.

    • Major ERCOT LSE
      $4.2M/yr· ERCOT
    • Texas retailer
      $3.8M/yr· ERCOT
    • ERCOT utility
      $3.8M/yr· ERCOT
    • Mid-Atlantic IOU
      $2.1M/yr· PJM
    • Chicago-area IOU
      $3.4M/yr· PJM
    • Midwest IOU
      $2.6M/yr· MISO
    • Gulf-area LSE
      $2.4M/yr· MISO
    • Michigan utility
      $2.1M/yr· MISO
    • Northern CA LSE
      $1.8M/yr· CAISO
    • Virginia IOU
      $3.1M/yr· PJM
    • Southern CA LSE
      $1.6M/yr· CAISO
    • Upstate NY IOU
      $1.8M/yr· NYISO
    • NYC-area IOU
      $2.1M/yr· NYISO
    • New England IOU
      $1.2M/yr· ISO-NE
    • SPP utility
      $1.2M/yr· SPP
    • Plains IOU
      $1.1M/yr· SPP

Illustrative only — MAPE reduction × avg hourly load × typical imbalance penalty × 8,760 hours. Past performance is not a guarantee of future results. Methodology · Disclaimer

Public benchmark

Territory-level accuracy, with the baseline visible.

Day-ahead MAPE over a 12-month holdout window. Each region measured against its own published ISO baseline.

Territory
ISO Baseline
Gramm
Reduction
CaliforniaCAISODetails →
4.80%
2.63%
45.2%
TexasERCOTDetails →
5.10%
1.56%
69.4%
Mid-Atlantic & MidwestPJMDetails →
3.90%
1.70%
56.4%
Central U.S.MISO
4.30%
1.67%
61.2%
New YorkNYISO
4.10%
1.76%
57.1%
New EnglandISO-NE
3.70%
2.46%
33.5%
Great PlainsSPP
4.60%
2.82%
38.7%
Evaluation window: Jan–Dec 2025. 8,760 hours per region. See full details →
Baselines: CAISO OASIS SLD_FCST, ERCOT Seven-Day Load Forecast, PJM DA, MISO DA, NYISO DA, ISO-NE DA, SPP DA.

Live API

One request, full forecast.

Bearer token auth, JSON response, prediction intervals included. Day-ahead ERCOT forecast in 47ms.

View API docs
GET /v1/demand/forecast?region=ERCOT&horizon=day_ahead
200 OK47msapplication/json
{
"region": "ERCOT",
"horizon": "day_ahead",
"generated_at": "2026-04-11T06:00:00Z",
"forecast": [
{ "hour": 1, "mw": 42318, "p10": 41205, "p90": 43431 },
{ "hour": 2, "mw": 41856, "p10": 40780, "p90": 42932 },
{ "hour": 3, "mw": 41294, "p10": 40250, "p90": 42338 },
{ "hour": 4, "mw": 40987, "p10": 39960, "p90": 42014 },
// ... 20 more hours
],
"mape_trailing_30d": 1.56,
}

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