TOU plans do not punish total usage—they punish when usage happens. A home that consumes the same kWh as last year can owe less simply because the dishwasher, EV, and dryer stopped buying electrons during the expensive window.
How Time-of-Use works for residential customers
Most TOU schedules define:
- On-peak — high $/kWh, often weekdays 4–9 p.m. summer
- Off-peak — low $/kWh overnight and mid-day shoulder
- Super-off-peak (some utilities) — cheapest deep-night block
Your bill multiplies each bucket by its rate. Two homes with identical annual kWh diverge wildly if one charges an EV at 6 p.m. and the other at 1 a.m.
Why utilities care about your clock
Peak demand drives infrastructure cost—substation upgrades follow the highest 15-minute interval, not your annual kWh. TOU passes that signal to the meter so customers who flex share fewer system costs.
Best appliances to move off-peak
Prioritize large, flexible, schedulable loads:
| Appliance | Shift tactic | Typical win |
|---|---|---|
| EV charging | Departure-time scheduling; avoid 5–9 p.m. plug-in starts | High $/session |
| Clothes dryer | Delay start to super-off-peak | Medium $/week |
| Dishwasher | “Delay 2h” after dinner | Small but easy |
| Pool pump | Timer to run 10 a.m.–2 p.m. or overnight | Steady kWh block |
| Water heater | Timer or heat-pump utility program | Depends on fuel backup |
Harder to shift: central AC during occupancy, cooking, home offices with afternoon cooling.
Automation beats reminders
- EV app: charge by finish time, not “start now”
- Smart plug + dryer delay for noise-allowed hours
- Utility rate APIs in Home Assistant for pre-cooling before peak
Measure what you can actually shift
Do not assume 80% of peak load is movable—HVAC and dinner cooking stay put. Use 30–50% as a first-pass planning figure, then raise it as automation proves reliable.
Enter your utility’s peak/off-peak kWh split, both rates, and a realistic shift percentage—the bar chart shows whether your spreadsheet discipline matches dollars on the bill.
When TOU shifting is weak
- Flat legacy rates
- Peak/off-peak spread under ~$0.08/kWh
- Renters without meter access or landlord approval for EV chargers
In those cases, efficiency upgrades beat scheduling—but when TOU exists, shifting is the fastest no-capex upgrade.
TOU literacy is household infrastructure. Run the flexible machines on the cheap clock, and let peak pricing fund your off-peak lifestyle.