Time-of-Use Tariffs Explained: How to Actually Cut Your Bill

If your electricity bill charges you different rates at different times of day, you're on a time-of-use (TOU) tariff. Done right, it's a genuine way to cut costs without spending a cent on new equipment — you just move the power-hungry stuff to the cheap hours. Done wrong, or ignored, it can quietly cost you more than a plain flat rate. Here's how to tell the difference.

What the three windows actually mean

A TOU tariff splits the day into blocks, each with its own per-kWh price:

Peak — the most expensive block, when grid demand is highest. In most Australian states peak typically runs around 2pm–8pm (later in some states), but the exact window is set by your distributor and retailer.
Shoulder — a middle rate, usually mornings and late evenings either side of peak.
Off-peak — the cheapest block, usually overnight and sometimes the middle of the day.

The single most important thing you can do: read your actual bill. The peak/shoulder/off-peak times and rates are printed on it (or in your plan's Basic Plan Information sheet). Times vary by distributor, state and even season — don't assume the "2–8pm" rule of thumb applies to you. Confirm your real windows before you change anything.

How to shift usage into the cheap hours

The goal is simple: run heavy loads during off-peak, avoid them during peak. The biggest movable loads in most homes are:

Hot water — often the single biggest shiftable load. Electric and heat-pump systems can usually be timed or put on a controlled off-peak circuit.
Dishwasher and washing machine — use the delay-start timer to run overnight or in off-peak.
Clothes dryer and pool pump — schedule for off-peak; a cheap plug-in timer does the job for the pool pump.
EV charging — if you have one, charging overnight on off-peak is where the real money is.
Air conditioning — the hardest to shift, because you want it during hot late-afternoon peak. Pre-cooling the house during shoulder/off-peak and coasting through peak can help.

Where the free daytime power fits in

From 1 July 2026, a federal offer called Solar Sharer is being rolled out through participating retailers. On an eligible opt-in plan it provides free power in an 11am–2pm window, capped at 24 kWh per day, and requires a smart meter. That middle-of-the-day slot is perfect for the loads above — running your dishwasher, washing, pool pump or hot water heater in that window could mean running them for nothing.

The catch: availability varies by retailer and state, and it's opt-in on a specific plan — so you'll need to confirm whether it's offered where you are before you count on it.

Here's the catch — TOU doesn't suit everyone

This is the honest bit. A time-of-use tariff only saves you money if you can actually move your usage out of peak. It can backfire if:

Your household is home and active in the late afternoon and evening. Families with kids, shift workers, or anyone running aircon and cooking through the 2–8pm peak may find a flat-rate tariff is cheaper overall.
You can't shift your biggest loads. If hot water, cooking and heating all cluster in peak and can't be moved, TOU may cost more.
Your peak rate is steep and your usage mix is peak-heavy. The gap between peak and off-peak rates matters — a small gap means less to gain from shifting.

The only way to know for sure is to compare your actual half-hourly usage data against both a TOU plan and a flat-rate plan. Many retailers and the government's Energy Made Easy site let you upload or compare usage. If your peak-hour usage is stubbornly high, staying on (or switching back to) a flat rate may genuinely be the better call.

A simple way to decide

Before committing to a TOU plan, work through this:

Pull your last bill and note the exact peak, shoulder and off-peak windows and rates.
Look at when your household actually uses power — roughly what share falls in peak versus off-peak?
List which loads you can realistically shift (hot water, dishwasher, washing, EV, pool pump) and which you can't.
Compare the numbers against a flat-rate plan for the same usage.

If you can move a decent chunk of usage — and especially if you have solar or access to a free daytime window — TOU can pay off nicely. If you can't, don't force it.

We sell no plans, panels or batteries — so we've no reason to talk you onto a time-of-use tariff, or off one. Our only job is to model your real usage and tell you honestly whether shifting your peak-hour power will save money, or whether a plain flat rate leaves you better off.

Want to know what actually pays for your place?

Get an independent, engineered read on your whole bill — solar, battery, tariff and the rebates you're really entitled to — for a small fixed fee. No system to sell, no sales call.

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Figures in this guide are current at the date of publication and indicative only — rebate and certificate values change over time (federal battery certificates step down each January and July), and state schemes are amended often. Confirm the current numbers for your situation before you commit. This is general information, not personal financial advice.