Skip to content
KardashevLabs
Live accuracy tracker

How good is ERCOT's own load forecast?

Every day ERCOT publishes a day-ahead forecast of Texas load, hour by hour. This page is not our model. It is ERCOT's own number, scored against what actually happened. History runs back to 2019 and updates daily. Transmission planning, reserve margins, and market prices lean on this forecast; when it misses, the miss shows up downstream.

How to read this page
MAPE (mean absolute % error). On average, how far off is the day-ahead forecast from what actually happened, as a percentage of actual demand. Lower is better. Utility-grade load forecasts typically run 1-3% MAPE.
Bias. Whether the forecast consistently runs high or low. Positive means ERCOT systematically under-forecasts (actual load comes in higher than predicted); negative means it over-forecasts. Near zero is best; a small nonzero bias that's stable is normal and not necessarily a flaw.
Why this matters. ERCOT commits reserves and clears the day-ahead market based on this forecast. A forecast that runs low on hot summer afternoons is exactly the condition that produces scarcity pricing and reliability risk. Tracking this publicly turns a number buried in operational reports into something anyone can watch.

Live track record

Hours scored
67,459
2019-01-01 → 2026-09-16
MAPE
2.43%
mean absolute % error, all-time
Bias
-0.47%
ERCOT over-forecasts, on average
MAE
1,196 MW
mean absolute error in megawatts
Day (UTC)MAPEBiasMAE
2026-09-160.75%-0.54%536 MW
2026-09-151.75%1.40%1,264 MW
2026-09-142.07%1.56%1,504 MW
2026-09-133.31%3.31%2,251 MW
2026-09-120.87%-0.45%608 MW
2026-09-110.90%-0.17%615 MW
2026-09-101.89%1.54%1,303 MW
2026-09-090.96%0.67%662 MW
2026-09-081.07%0.20%838 MW
2026-09-070.92%-0.72%580 MW
2026-09-061.44%0.72%1,031 MW
2026-09-051.03%0.54%779 MW
2026-09-040.70%-0.70%537 MW
2026-09-032.27%0.05%1,688 MW
2026-09-021.19%1.19%827 MW
2026-09-011.05%-1.05%741 MW
2026-08-310.96%0.86%689 MW
2026-08-301.78%1.78%1,273 MW
2026-08-291.66%-1.55%1,160 MW
2026-08-281.75%1.70%1,340 MW
2026-08-271.65%1.22%1,272 MW
2026-08-261.74%0.43%1,292 MW
2026-08-251.52%-1.24%1,177 MW
2026-08-241.42%0.73%1,049 MW
2026-08-231.40%-1.37%1,029 MW
2026-08-220.52%-0.43%390 MW
2026-08-211.02%0.36%784 MW
2026-08-200.44%0.06%356 MW
2026-08-191.02%0.84%722 MW
2026-08-180.88%0.51%621 MW

Methodology

Forecast and actual load come from EIA-930 (respondent ERCO): the DF series is ERCOT's published day-ahead demand forecast, the D series is realized demand. Both are hourly, system-wide. Every hour is scored exactly once, permanently: nothing here is revised after the fact.

This is a companion to our RT-DA spread forecast: that page scores our own model's price predictions; this one scores ERCOT's own load forecast. Same discipline: public, immutable, updated daily.