Electricity Power Use

What drives power use in Toronto?

Daily Power Use

Use top left buttons or bottom slider to explore different time periods

Factors Impacting Power Use

Feeding power use data along with several time and environmental factors into an ML boosting model then into a SHAP explainer model reveals the impact of each factor

Top 3 impactful factors

  • Hour of day is the most important factor with 2200 MWh swing throughout the day (average hourly use = 5800 MWh)
  • Temperature The warmest hours of the year can increase power use 3x the lowest use hours
  • Weekday vs Weekend is also very impactful with up to 1500 MWh throughout the week

There's a few minor factors that also have some impact

  • Holidays shows significant power reduction
  • High humidity and daylight weather factors also increase power use slightly



SHAP values attempt to capture the effect of each factor independantly
Factors with the greatest impact are listed top to buttom
Red dots = higher value for the factors (higher temperature, later hours in the day)
Dots to the right = increases power use

Power use is highly cyclical

1. Daily power use ramps up in the morning, peaks around 5-7pm and drops to a low around 3am
2. The weekly cycle is also very visible, with weekends (days 6-7) using significantly less power than weekdays (days 1-5); Sunday's power use cycle starts increasing later in the day vs Saturday

Temperature is the other key factor

  • Power use lowest around 13 C and increase at both hotter and colder temperatures; usage during hours of the hottest summer afternoons can triple the lowest midnight hours
  • Highest hourly power use in the last 10 years was 10,285 MWh which occured on 2011-07-21 2pm with temperature at 37.2 C

    • Temperature increase will significantly increase peak power usage

    Simulated 2021 power usage with ML model using modified temperatures

    • Power usage increases are greatest during the summer, flat during spring, and may even decrease during winter as heating needs lessen
    • Small temperature increases during the summer can have great effect on peak power usage; +2c on the hottest days can increase peak power use up to 7%

      • Sources: IESO (Power); Environment Canada (Weather)
      Models: Catboost (ML Gradient Boosting); SHAP (ML Model Explainer)