check_hot_water_switch
Use when someone asks whether a heat pump hot water system is worth it in Australia, which rebates they can stack, how much a heat pump costs after rebates, or how long it takes to pay off — including "can I combine the STC rebate with Victorian Energy Upgrades or Solar Victoria", "do I qualify", and "is a heat pump cheaper to run than gas". Given a postcode, the current hot water system and a few household facts, returns the rebates actually stackable at that postcode (with each scheme's eligibility gates and source), the net-of-rebate outlay, the payback period, and which term — rebates, the avoidable gas supply charge, the energy saving, or a replacement you were buying anyway — is really carrying the decision. Modelled estimate, not financial advice.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| people | No | household size (drives hot water demand) | |
| postcode | Yes | AU postcode — rebate eligibility is postcode-gated | |
| locally_made | No | an eligible locally made unit, which raises the Victorian caps | |
| current_system | Yes | what you have now | |
| owner_occupier | No | tenure — gates the means-tested state rebates | |
| property_value | No | property value — Solar Victoria requires under $3,000,000 | |
| replacement_due | No | true if the existing system is failing and you were replacing it anyway | |
| household_income | No | combined owner taxable income, for means-tested schemes (Solar Victoria caps at $150,000) | |
| system_age_years | No | age of the system being replaced; Solar Victoria requires at least 3 years | |
| building_age_years | No | age of the building; Victorian Energy Upgrades requires at least 2 years | |
| gas_only_for_hot_water | No | true if hot water is your last gas appliance, so the daily supply charge can be avoided |