Australian home energy calculators
Free calculators for Australian homes: batteries, appliances, heating and cooling, transport, electricity and solar. Every formula, rate and source is shown.
BatteriesBattery rebate calculatorThe federal battery rebate and payback for your battery, with rates for each state.$3,367 on 13.5 kWh until 31 Dec 2026BatteriesBattery buy now or wait calculatorThe rebate you lose by waiting, and how far prices must fall for waiting to pay off.$555 lost on 13.5 kWh by waiting past 31 Dec 2026BatteriesBattery size calculatorWhat size home battery your evening use and solar can fill, with the rebate and payback for common sizes.12.4 kWh for 3 people and 10 kW of solarBatteriesAdd a battery to solar calculatorPayback for a battery on the solar you already have, with the QLD, SA and ACT premium feed-in rules.10.2 years payback on 10 kWh until 31 Dec 2026BatteriesBlackout backup calculatorHow long your home battery runs the fridge, lights and Wi-Fi in a power outage.6.3 days on a full Powerwall 3BatteriesBattery runtime calculatorHow long a 12, 24 or 48 V battery runs a load, with inverter losses and idle draw counted.10.8 hours for an 80 W TV on 100 Ah lithiumBatteriesCaravan fridge battery calculatorThe battery a 12 V fridge needs off-grid, and whether your solar and DC-DC charger keep up.68 Ah for 3 days of a 46 L fridgeBatteriesBattery charge time calculatorHours to charge a battery from a charger, or days from a solar panel, with the slow last stage shown.3.5 hours for 100 Ah lithium on a 25 A chargerBatteriesInverter size calculatorThe inverter size your appliances need, their start-up surge, and the current they pull from the battery.2,700 W for a 2,000 W heater and a fridge
Battery rebate by state
The federal rebate is the same everywhere. Electricity rates and state schemes are not. Each state page says what that state offers and shows the payback at its default rates.
AppliancesAppliance running cost calculatorWhat an appliance costs to run an hour, a day and a year at your rate.$128 a year for a fridgeAppliancesAir fryer vs oven costMeasured kWh per dish: an air fryer against a fan, conventional or gas oven, per cook and per year.$29 a year saved at 3 meals a weekAppliancesHeat pump hot water cost and rebateHeat pump against electric and gas hot water: yearly cost, STCs by postcode, state rebates and payback.$793 a year saved vs a peak-rate electric tankAppliancesCost to run a dishwasherCost per load and per year from the dishwasher label, your program and your state electricity and water prices.$0.32 a load on normalAppliancesGas vs induction cooktopYearly cooking cost on gas, induction and ceramic, the gas supply charge you save by leaving gas, and the payback.$325 a year saved by leaving gasAppliancesStandby power costThe watts, kWh and dollars your devices use on standby each year, and which ones are worth switching off.$135 a year on standby
Heating & coolingHeater running cost comparisonCompare fan, oil, panel, gas and reverse-cycle heaters at the same heat, per hour and per winter.$70 a winter on reverse-cycleHeating & coolingAir conditioner running cost calculatorWhat your split system or ducted aircon costs a year from its energy label, and per hour, at your rate.$511 a year for a 7.1 kW splitHeating & coolingWood heater vs reverse-cycleWhat a winter on your wood heater costs against reverse-cycle for the same heat. Defaults to bought wood in Victoria; set your own price.$1,900 a winter of bought wood in VictoriaHeating & coolingWhat one degree costs youWhat turning your thermostat up or down a few degrees does to your heating or cooling bill, as a range from government sources.$30 to $60 one degree on an example $600 heating seasonHeating & coolingEvaporative cooling running costWhat ducted evaporative cooling costs a summer in electricity plus water, at your state's rates.$143 a summer for a 10.4 kW ducted system, power plus water
TransportEV charging cost vs petrol calculatorWhat your EV costs to charge per 100 km and per year, at home, on EV plans and fast chargers, against petrol.$2,681 a year less than petrolTransportFuel cost calculatorAny trip's fuel cost at the latest weekly petrol or diesel price (week ending 27 September 2026), with Green Vehicle Guide car figures, per km and per person.$33.84 Sydney to Canberra, one wayTransportFuel consumption calculatorYour real L/100km from one fill-up, your cost per km, and how it compares with the car's label and AAA road tests.8 L/100km example: 500 km on 40 LTransportEV charging time calculatorHow long your EV takes to charge on a power point, a wall charger, three-phase or a DC fast charger, with Australian specs.5 h 23 min MG4 Urban 54, 20 to 80%, 7 kW wall charger
ElectricityElectricity cost per kWh calculatorYour real price per kWh from a bill, with and without the supply charge, against your state’s average.32c/kWh Australian average usage priceElectricitySolar Sharer and Midday Power Saver calculatorIs 3 hours of free power a day worth switching for? Your plan against the Solar Sharer or Midday Power Saver, with a battery, solar or an EV.$127 a year less in Ausgrid, dishwasher moved to middayElectricityWatts to amps calculatorConvert watts, kW, amps and kVA at Australian voltage, and check a load against a power point.10.43 A for 2,400 W at 230 VElectricityElectricity bill calculatorEstimate your power bill for a quarter, month or year, and see what a home like yours pays on the default offer.$582 a quarter, 2 people in Sydney, Ausgrid default offerElectricityPeak and off-peak times calculatorPeak, shoulder and off-peak times for every network we cover, and whether time of use beats a flat rate for your home.34.8% break-even peak share, Ausgrid
SolarSolar feed-in tariff calculatorWhat your solar exports earn a year at your feed-in tariff, and what the same power saves used at home.$624 a year for 10.5 kW in SydneySolarSolar EV charging calculatorHow much of your EV charging your rooftop solar can cover, by month and charger type, how many panels the car needs and what you save.1.45 kW of panels makes the energy for 12,600 km a year (Model Y AWD 600 km, Sydney)
Where the numbers come from
We prefer official sources: regulators, government schemes and published tariffs. We review every figure at least every 90 days, and each calculator shows the date it was checked.
- 50 topics · 290 sources
- Reviewed 23 September 2026
