Gridly
Flat Rate Tariff
An electricity pricing structure where the same rate per kWh applies regardless of when you use electricity. Common across Australia for standard residential connections. Simpler to understand than time-of-use tariffs but offers no financial incentive for demand shifting.
What it is
A flat rate (also called a single rate or anytime rate) tariff charges the same price per kWh regardless of time. Most standard residential electricity connections in Australia default to flat rate pricing. The rate typically sits between 28¢/kWh and 42¢/kWh depending on the network and retailer.
The daily supply charge (sometimes called the service to property charge) is separate and applies regardless of usage - typically $0.90–$1.20 per day.
The solar trade-off
For most solar households without battery storage, flat rate is generally fine. Solar-generated electricity avoided during the day saves you the flat rate (say 32¢/kWh), which is straightforward to model. There’s no time-of-day complexity - every kWh self-consumed during daylight hours is worth exactly the flat rate.
The limitation is that flat rate gives you no incentive to shift load to cheap periods, because there are no cheap periods. A dishwasher run at midnight costs the same as one run at noon. This matters more as the grid moves toward TOU structures that better reflect actual wholesale costs.
When to consider switching to TOU
If you have or are considering battery storage, TOU tariffs become more attractive because they allow the battery to capture the spread between cheap overnight charging and expensive peak discharging. On a flat rate, a battery still has value (for solar self-consumption and backup), but the pure arbitrage case is weaker.
Without a battery, switching to TOU is risky unless you can genuinely shift your heavy loads (air conditioning, cooking, EV charging) out of the peak window. Many households that switch to TOU without behavioural changes or storage end up paying more than on flat rate, because their natural usage peaks align with the TOU peak period.
Check your historical interval data (available from your retailer or via the AEMO Meter Data Portal) before switching - it will show your hourly usage profile and let you model what you’d pay under alternative tariffs.