Time-of-use: price changes by time of day
On a time-of-use (TOU) plan, electricity costs more during the evening peak and less overnight and on weekends. If you can shift when you use power, this tariff rewards you for it.
How it works
A time-of-use tariff splits the day into two or three pricing bands:
Peak
The most expensive band. Usually weekday afternoons into the evening (e.g. 3pm–9pm). This is when everyone gets home, turns on the AC, cooks dinner, and watches TV — grid demand is highest.
Shoulder
A middle rate on some (not all) plans. Typically covers mid-morning to early afternoon on weekdays. Not every retailer uses a shoulder band — some just have peak and off-peak.
Off-peak
The cheapest band. Overnight hours, early morning, and often all weekend. This is when grid demand is lowest and wholesale prices are cheapest.
What the day looks like
Illustrative weekday schedule. Exact times vary by state, distributor, and retailer.
Worked example: same 15 kWh, different cost
Imagine a household using 15 kWh in a day. On a flat rate vs. TOU plan, the daily cost can be quite different depending on when those kWh are used:
| Scenario | Usage split | Daily cost |
|---|---|---|
| Flat rate (28c/kWh) | 15 kWh × 28c | $4.20 |
| TOU — mostly peak | 10 kWh peak (35c) + 5 kWh off-peak (18c) | $4.40 |
| TOU — mostly off-peak | 5 kWh peak (35c) + 10 kWh off-peak (18c) | $3.55 |
The savings are real
Typical peak windows by state
| State | Typical peak window |
|---|---|
| NSW | 2pm–8pm or 4pm–8pm weekdays |
| QLD (SEQ) | 4pm–9pm weekdays |
| VIC | 3pm–9pm every day |
| SA | 6pm–10pm (summer peak) |
| TAS | 7am–10am and 4pm–9pm weekdays |
Always check your actual plan documents — times vary by distributor and retailer even within the same state.
Who TOU tariffs suit best
- Solar households — you’re already using free solar during the day, reducing your peak-priced imports.
- EV owners — charge overnight at off-peak rates instead of evening peak.
- Flexible schedules — if you can run laundry, dishwashers, and pool pumps outside peak hours.
- Battery owners — charge from solar midday, discharge during peak to avoid buying expensive grid power.
If you can’t shift much usage and tend to use most power in the evening, consider a flat rate instead — TOU only saves money if you actually shift loads.