AC Running Cost Calculator
Hamilton, ON
Find out what your air conditioner actually costs to run each month β using Hamilton Hydro and Alectra’s real Ontario electricity rates, not a generic national number.
β‘ Hamilton Hydro / Alectra Rates
π Monthly & Annual
π Free
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Get Free QuotesWhat Your AC Is Costing You Every Month in Hamilton
Hamilton homeowners are served by two main utilities: Hamilton Hydro (serving most of the old city) and Alectra Utilities (covering significant portions of the greater area). Both operate under Ontario’s regulated electricity rate structure, which means the same TOU periods and similar commodity rates. The key variable is your rate plan β Time-of-Use billing (where time of day affects your rate) versus Tiered billing (where total usage volume determines your rate tier).
For a typical Hamilton home running a 2.5-tonne, 14 SEER2 central AC approximately 8 hours per day over 90 summer days, total cooling electricity cost runs roughlyΒ $195 to $360 per summerΒ depending on how much of that runtime falls in on-peak hours.
| AC Size | SEER2 | Monthly Cost (Ontario) | Full Summer |
|---|---|---|---|
| 1.5 tonnes | 14 SEER2 | $50 β $80 | $100 β $160 |
| 2 tonnes | 14 SEER2 | $70 β $105 | $140 β $210 |
| 2.5 tonnes | 14 SEER2 | $85 β $130 | $170 β $260 |
| 2.5 tonnes | 18 SEER2 | $65 β $100 | $130 β $200 |
| 3 tonnes | 14 SEER2 | $105 β $155 | $210 β $310 |
| 3 tonnes | 20 SEER2 | $72 β $110 | $145 β $220 |
*Based on Ontario TOU off-peak-biased operation, ~8 hrs/day, 90 cooling days, OER applied. Actual costs vary with usage timing, home insulation, and whether TOU or Tiered billing applies.
Ontario TOU Billing and Your Hamilton Summer Bill
The Time-of-Use rate structure creates a situation where running your AC for the same number of hours costs dramatically different amounts depending on when those hours fall. Ontario’s summer TOU structure means a weekday afternoon (11 AMβ5 PM) costs roughly twice as much per kWh as a weekend morning. For Hamilton homeowners who are home during peak hours β or who don’t have a programmable thermostat β this is the biggest controllable driver of summer electricity bills.
π Off-Peak (~$0.087/kWh)
Weekdays 7 PMβ7 AM; all-day weekends and holidays. Best time to run your AC, charge EVs, and do high-draw appliances. Pre-cool your home here before peak hours begin.
π€οΈ Mid-Peak (~$0.113/kWh)
Weekdays 7β11 AM and 5β7 PM. Moderate rates β fine for modest AC operation during cooler parts of the day. The evening mid-peak window is when many Hamilton homes are actively occupied and cooling demand is real.
βοΈ On-Peak (~$0.179/kWh)
Weekdays 11 AMβ5 PM. This 6-hour window is responsible for most of Hamilton’s summer electricity bill shock. Running a 3-tonne AC at full load here costs roughly 2Γ the off-peak rate per hour.
π Ontario Electricity Rebate (OER)
The province applies an automatic ~11.7% rebate to all residential electricity bills. It’s built into your Hamilton Hydro or Alectra bill automatically β no application needed. Our calculator includes it.
π‘ How Hamilton Homeowners Cut AC Electricity Bills
- Set thermostat to 25β26Β°C instead of 22Β°C β each degree warmer saves 5β8% on cooling electricity in Ontario
- Pre-cool to 22Β°C before 11 AM (off-peak), then let the house coast to 25Β°C through the afternoon peak window
- Install a smart thermostat that auto-schedules around TOU periods β $80β$150 savings/summer typical in Hamilton
- Use ceiling fans β they let you feel 3β4Β°C cooler at any thermostat setting, dramatically reducing compressor runtime
- Close blinds on south and west-facing windows 11 AMβ5 PM β blocks 30β40% of peak solar heat gain
- Annual AC tune-up β dirty coils reduce efficiency 15β20%, meaning more electricity for the same cooling
Frequently Asked Questions
I'm on Tiered billing, not TOU. Which is better for Hamilton AC users?
It depends on your usage pattern. Tiered billing charges a flat rate up to a monthly threshold (roughly 600 kWh/month in summer), then a higher rate above it. If you run a large AC and frequently exceed the threshold, TOU can actually be better if you can shift most runtime to off-peak hours. If you’re a lower consumer who rarely exceeds the threshold, Tiered billing is often simpler and cheaper. Your Hamilton Hydro or Alectra account shows your historical usage β that data tells you which structure would have saved you money in past summers.
How do I calculate my AC's exact kWh consumption?
The formula: (Tonnes Γ 12,000 BTU/h) Γ· (SEER2 Γ 1,000) = kW draw. A 2.5-tonne, 14 SEER2 unit: (2.5 Γ 12,000) Γ· (14 Γ 1,000) = 2.14 kW per hour of operation. At 8 hours/day, that’s 17.1 kWh daily. Multiply by Ontario’s blended rate (~$0.12β$0.14/kWh after OER) and you get roughly $2.05β$2.39/day, or approximately $60β$72/month for a 30-day billing cycle β assuming moderate off-peak bias.
Is Hamilton Hydro's rate different from Alectra's for AC purposes?
The regulated electricity commodity rates (the TOU and Tiered rates set by the Ontario Energy Board) are the same for both utilities. The difference shows up in the distribution and delivery charges, which vary slightly between utilities. For the purposes of estimating AC operating cost, the commodity rates are what drive the calculation β both utilities are close enough that the difference is under 5%.
Book an AC Tune-Up
A clean, properly charged AC uses significantly less electricity. Annual tune-ups typically pay for themselves in the same summer.