How do I read my power bill to work out what solar and battery I need?
You need three things from your bill: how much power you use per day (kWh), when you use it (peak, shoulder, off-peak) and what the supply charge is. Send us one or two recent bills and we do the rest as part of your free energy assessment.
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We’ll text you within minutes. Or call 0483 903 020.
The parts of the bill that matter
- Usage (kWh): the energy you used in the billing period. Divide by the number of days for your daily average. This sizes the solar and the battery.
- Usage charge: the price per kWh. The AER calls this the variable charge: what you pay for each unit you use.
- Supply charge: a fixed daily charge for being connected. It is not based on how much you use, so solar and batteries do not change it.
- Time-of-use periods: some tariffs charge different prices for peak, shoulder and off-peak. The split of your usage across those periods tells us how much a battery can shift.
- Demand charges: on some tariffs, mostly businesses, a charge based on your highest use in a short period. A battery can help with these on some tariffs.
- Export or feed-in: what you are paid for solar you send to the grid, if you have solar.
What we read from it
- Your daily use, and whether it is mostly day or night. Day-heavy suits solar; night-heavy suits a battery.
- Seasonal swings: air conditioning in summer, heating in winter.
- Whether you already have solar, and how much you export.
- Your tariff type, because the right design depends on how the bill is worked out.
From that we size solar and battery to your real usage: a bigger battery is not always better. See what size home battery do I need? and adding a battery to existing solar. We do not quote prices online or promise savings, because they depend on your usage and your retailer.
No bill handy?
Your retailer’s app or website holds past bills. If you have a smart meter, your usage data is often there too, and it is even better than a bill. We can work from either.
Why locals choose us
- Our own in-house team designs every system and does every install. 25 years in solar and large commercial electrical work. No subcontractors.
- A face-to-face site visit before every install: compliant battery position, switchboard and RCBO check, no surprises on the day.
- SAA-accredited installer and Sigenergy-approved, with a 25-year workmanship warranty on our installation work.
Questions we get asked
How many bills do you need?
One or two recent bills is enough to start, ideally from different seasons. We can also work from your retailer’s usage data.
Which number on the bill is my usage?
The kWh figure, usually shown as total usage for the period, and often split into peak, shoulder and off-peak. Divide by the days in the period for a daily average.
Does solar reduce my supply charge?
No. The supply charge is a fixed daily charge, not based on usage.
What is a demand charge?
On some tariffs, a charge based on the highest amount of power you use in a set period, commonly a 30-minute window. More common for businesses.
Do I need a battery?
Not always. We tell you honestly whether one makes sense for your usage.
Sources
Last checked 7 October 2026. Only the manufacturer’s, the network’s or the government’s own documents are used; app menus and defaults change between models and versions, so if your screen looks different, call us rather than guess.
- Australian Energy Regulator: Your energy bill
- Energy Made Easy (Australian Government): Understanding gas and electricity charges
- Australian Energy Regulator: About energy bills fact sheet
