Energy Rebate & Upgrade Cost Calculator Australia

AUSTRALIA · REBATE & UPGRADE COST CALCULATOR

Compare the upfront cost of a household energy upgrade before and after a confirmed rebate, grant or discount. You can also add your own annual bill-savings estimate to calculate a simple payback period.

HomeBillLab calculator

Estimate upgrade cost after rebates and discounts

Enter the project cost and a rebate, grant or discount amount you have already confirmed. This calculator works out an estimated out-of-pocket cost and, optionally, a simple payback from your own annual-savings estimate.

This calculator does not determine eligibility. Australian rebate and assistance programs vary by location, technology, household circumstances and program dates. Use an amount or percentage from the relevant official program, provider or approved quote.
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Use the total amount you are actually comparing, including GST where applicable to the quote.
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Optional: retailer discount, certificate value or another confirmed contribution.
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Optional. Enter your own estimate if you want a simple payback calculation.
Estimated out-of-pocket upgrade cost—Before finance costs, maintenance, tariff changes or any unconfirmed support.
Primary rebate / grant—
Other discounts—
Total confirmed support—
Support as share of project cost—
Simple payback—
Does this tell me which rebates I qualify for?

No. Eligibility can depend on your state or territory, household circumstances, property, technology, approved provider, application timing and other program conditions.

What should I enter as project cost?

Use the cost basis that matches the rebate or quote you are evaluating. If the official program applies only to eligible costs or has a cap, use the eligible amount stated by that program rather than assuming the whole project receives the percentage.

Is simple payback a guaranteed return?

No. It is only net upfront cost divided by the annual savings value you enter. Real savings can change with tariffs, equipment performance, climate, maintenance and household use.

Privacy: calculations run in your browser. The numbers you enter are not submitted to HomeBillLab.

What this calculator is designed to do

Fixed rebate

Use this when the program or provider gives you a specific dollar amount.

Percentage rebate

Use this when the support is stated as a percentage of an eligible cost. Check for caps or exclusions before entering the percentage.

Other confirmed discounts

Add another known contribution such as a retailer discount or certificate value, but do not include amounts you have not confirmed.

Optional simple payback

If you already have a credible annual energy-bill savings estimate, the calculator can divide net upfront cost by that annual amount.

Eligibility comes from the official program, not this calculator

Australian household-energy rebates and assistance can vary by state or territory, technology, eligibility category and program date. HomeBillLab deliberately does not embed a permanent list of rebate amounts into this calculator.

Confirm the current program rules first, then use this tool to compare the numbers that apply to your situation.

How the calculation works

Estimated net cost = project cost − confirmed rebate/grant − other confirmed discounts.

For percentage mode, the calculator first multiplies the entered project cost by the rebate percentage. If a program only applies the percentage to an eligible-cost cap, enter the appropriate eligible cost or confirmed support amount rather than applying the percentage to the entire quote.

Official Australian rebate information

Reviewed: 21 August 2026.

Energy rebate calculator FAQs

Can I use this for solar, batteries, hot water or insulation?

Yes, as a generic net-cost comparison, provided you enter the confirmed project cost and support amount that actually applies to the upgrade.

Can two rebates be combined?

Only if the relevant program rules allow it. The calculator can add another confirmed discount, but it does not determine whether programs can legally or administratively be stacked.

Why does the calculator reject support above the project cost?

For a simple out-of-pocket comparison, total entered rebates and discounts cannot exceed the project cost. If a scheme is structured differently, use the official calculation instead.

Should I include finance costs?

No finance cost is added automatically. If you are using a loan, compare its fees and interest separately because simple payback based only on upfront net cost will not include financing costs.

Related Australian energy guides

Use these guides to check assumptions, follow worked examples and compare common household scenarios.

Browse all Rebates guides