WattNavi Data Sources and Methodology: How We Source Data

Our rules for data

Official first. If a regulator or government publishes a figure, we use theirs.
Named and dated. Every page lists its sources and when we last checked them.
No estimates dressed as facts. Worked examples state their assumptions, such as appliance efficiency or how much solar a home uses.
Industry data only where nothing official exists. This applies to installed solar and battery prices, which come from the Solar Choice price indices.

Regulated electricity prices

State rate pages, average bills and calculators use the 2026-27 regulated prices: the AER's Default Market Offer in NSW, South East Queensland and South Australia, the Victorian Default Offer, the QCA's notified prices for regional Queensland, the regulated standing offers in Tasmania and the ACT, and the government-set tariffs in WA and the NT. A "typical bill" means 4,000 kWh a year on the state's regulated tariff, supply charge included.

Retail plan data and rankings

Retailer pages and comparisons use every generally available residential plan published to the AER's Energy Made Easy product reference data under the Consumer Data Right, as at 14 October 2026. That data excludes GST, so we add it to usage and supply charges.

How we price and rank electricity plans
Usage levels	2,500, 4,000 and 6,500 kWh a year
Plans ranked	Flat-rate plans that any household in the network can join
Left out	Plans restricted to members, existing customers or particular equipment; wholesale-price plans, whose rates are estimates
Discounts	Guaranteed discounts included; conditional discounts such as pay on time left out

Usage benchmarks and climate zones

Household usage figures come from the AER's residential consumption benchmarks (Frontier Economics, December 2020), by household size, season and climate zone. City pages assign each town its zone from the Australian Building Codes Board's climate zone tables, and its solar zone from the Clean Energy Regulator's postcode list.

Local solar, battery and heat pump installation counts are CER postcode data to August 2026.

Electricity and gas networks

Network size, ownership and reliability come from the AER's State of the energy market 2025 data (electricity figures as at 30 June 2024). Faults and leak numbers were checked on each network's own website or the state safety regulator.

Rebates and concessions

Every program page takes its amounts and eligibility from the government agency that runs it, checked in October 2026. The program pages list 49 programs in total.

Show all 42 rebate sources

Solar and batteries

STC rules, zone ratings and the battery discount schedule come from the Clean Energy Regulator. State solar and battery programs come from the state governments. Because there is no official price series for installed solar or batteries, system and battery prices come from the Solar Choice Price Index and Battery Price Index, labelled as industry data wherever they appear.

Brand pages

Panel, inverter and battery specifications and warranty terms come from manufacturers' Australian datasheets and warranty documents. Terms vary by model, so each page tells readers to check the certificate for their exact product.

Gas

Gas plan prices come from the AER's plan data as at 14 October 2026. We price each plan for a real postcode in each gas network using the AER's gas usage benchmark for the state, its seasonal pattern and each plan's block and seasonal rates. WA gas prices are the WA Government's regulated maximum tariffs.

Updates and corrections

Regulated prices change each July, and some programs change mid-year. We recheck sources when they change and update the "last checked" date on each page. If you find an error, please contact us. Read more about WattNavi.