Total HVAC kWh
—
heat pump + air handler, all time
Air Handler Share
of combined HP+AH consumption
Pearson r (AH vs Temp)
—
target: −0.65 to −0.80
Whole-Home kWh
—
Alectra metered, all time
Grid Carbon Intensity
—
gCO2eq/kWh · Ontario grid · live
Fossil Fuel %
—
Ontario grid generation mix · live
Air Handler ↔ Outdoor Temperature Correlation
Pearson r — last 60 days of hourly data
—
Aux Heat Runtime — Full Heating Season
Hourly air handler wattage vs outdoor temperature · Nov 2025 – present · fix date: Apr 23, 2026
Pre-Fix AH Firing Rate
—
% of hours aux heat active
Post-Fix AH Firing Rate
—
% of hours aux heat active
Pre-Fix Avg Temp When Firing
—
°C · should be below −5°C
Pre-Fix Aux Heat kWh
—
resistance strip consumption
Vertical line marks fix date (Apr 23, 2026). Air handler wattage should trend toward zero post-fix except in extreme cold.
Pre-Fix: AH Wattage vs Outdoor Temp
Post-Fix: AH Wattage vs Outdoor Temp
HP vs Air Handler — Monthly kWh
Daikin Skyport data — heat pump and resistance strips
Air Handler Share %
Resistance strip use as % of total HVAC — should drop post-fix
Whole-Home Daily Consumption
Alectra metered kWh — last 30 days
Outdoor Temperature
Open-Meteo hourly reanalysis — Southern Ontario
Alectra Billing History
Electricity billing history
| Period | Days | Adj kWh | Total Bill | Rate Plan |
|---|---|---|---|---|
Loading billing data… | ||||
Ontario Grid Carbon Intensity
gCO2eq/kWh — 10-day history · Electricity Maps via Home Assistant
Fossil Fuel Percentage
% of Ontario grid generation from fossil sources — 10-day history
TOU vs Ultra-Low Overnight — Rate Comparison
Supply charges only · OEB rates effective Nov 1 2025 · based on actual Sense consumption pattern
TOU Total (supply)
—
your current plan
ULO Total (supply)
—
if you switched
Estimated Difference
—
supply charges over period analysed
Your TOU Consumption Breakdown
How ULO Would Classify Same Hours
Recommendations
OEB Rate Reference (supply charges only)
| Period | Hours (weekdays) | TOU ¢/kWh | ULO ¢/kWh |
|---|---|---|---|
| Overnight | 11pm – 7am | 9.8 (off-peak) | 3.9 |
| Morning off-peak / ULO off-peak | 7am – period start | 9.8 | 11.5 |
| Mid-peak (winter) / On-peak (summer) | 11am – 5pm (summer) | 14.4 / 20.3 | 11.5 |
| On-peak (winter) morning | 7 – 11am | 20.3 | 11.5 |
| ULO On-peak / TOU On-peak evening | 4 – 9pm (ULO) · 5 – 7pm (TOU) | 20.3 | 39.1 |
Weekends and statutory holidays = off-peak all day (TOU) or overnight/off-peak (ULO). Delivery, regulatory charges, and HST are identical on all plans.
Data Sources
Sense Energy Monitor (hourly device-level power draw) ·
Daikin Skyport cloud API (monthly HP + AH kWh) ·
Open-Meteo historical reanalysis (hourly temperature, Southern Ontario) ·
Alectra Utilities PDF bills (18 months, manually parsed + loaded) ·
Electricity Maps via Home Assistant (carbon intensity + fossil fuel %, zone CA-ON, 15-min polling)
Key Finding
Pre-fix Pearson r between air handler wattage and outdoor temperature was −0.145 (R² = 0.02),
indicating the aux heat lockout was set to +10°C (Daikin default) instead of −5°C.
Resistance strips were firing at mild temperatures, costing an estimated
$730–$1,200/year in unnecessary electricity consumption.
Issue resolved by Shipton's Heating & Cooling, May 2026.
Stack
SQLite database · Python (pandas, sqlite3, requests) ·
Windows Task Scheduler (hourly export) ·
Chart.js · Vanilla JS ·
Statistical analysis: Pearson correlation, regression, time-series decomposition