How to read your electricity bill (and the three numbers that matter for solar)

Every retailer lays out its bill differently, but the same few figures are on all of them. These are the ones that decide what solar and a battery can do for you.

1. Your usage (kWh)

Look for 'usage', 'consumption' or 'general usage', measured in kilowatt-hours (kWh), for the billing period. Divide by the number of days to get your average daily use. Some bills split it into peak, off-peak and shoulder times: that tells us when you use it.

2. Your price per kWh

This is the rate you pay for each kWh from the grid, often 25 to 40 cents. Every kWh your solar or battery covers is one you don't buy at this price.

3. Your feed-in tariff

If you already have solar, your bill shows the electricity you exported and the credit per kWh. Feed-in credits are usually much lower than the price you pay, which is why using your own solar (or storing it) is worth more than exporting it.

Things you can ignore for sizing

• The daily supply charge: you pay it with or without solar.
• Your account number, NMI and personal details: we don't need or ask for them.
• Discounts and concessions: they change what you pay, not how much you use.

When you upload your bill to RENUABL, we read these figures for you and only keep the numbers: the file itself isn't stored. We also check the bill is for the address you entered.