Australia leads the world in rooftop solar adoption, but the booming market has attracted installers of varying quality — and contracts of varying fairness. A solar panel installation typically costs $4,000-$15,000+ after rebates, and the system is expected to last 25+ years. The contract you sign determines your warranty protection, performance guarantees, and recourse if things go wrong. The difference between a reputable installer and a problematic one often shows up in the contract terms: vague performance claims, limited warranties, and missing compliance details are the clearest red flags.
What is a Installation Agreement?
A solar panel installation contract is an agreement between a homeowner and a solar installer for the supply and installation of a photovoltaic (PV) system. It covers the system specifications (panel brand, model, wattage, inverter type), installation timeline, total cost (including any rebates applied), payment terms, warranties (manufacturer's product warranty, performance warranty, and installer's workmanship warranty), grid connection obligations, and compliance requirements. In Australia, installers should be Clean Energy Council (CEC) accredited, and the system should be designed and installed to CEC guidelines and Australian Standard AS/NZS 5033.
Red flags to watch for
CEC accreditation is required to create Small-scale Technology Certificates (STCs) — the government rebate that reduces your upfront cost. Non-CEC installers may offer lower prices but you'll lose the STC rebate, and their work may not meet Australian Standards.
Without specific product details in the contract, the installer can substitute cheaper components. You might pay for Tier 1 panels and receive an unknown brand with inferior performance and shorter warranty life.
Reputable installers provide an estimated annual energy generation (kWh) for your specific roof orientation, shading, and location. Without this, you have no basis to assess whether the system is delivering on its promise.
CEC guidelines recommend a minimum 5-year workmanship warranty from the installer. Manufacturer warranties cover the panels and inverter, but installation defects (roof leaks, wiring issues, mounting failures) are covered by the installer's own warranty.
Reasonable payment terms might be a deposit (10-20%), progress payment, and final payment after installation and successful grid connection. Full upfront payment removes your leverage if problems arise.
Your system can't export power (and earn feed-in tariff credits) until your distribution network service provider (DNSP) approves the connection. If the installer doesn't handle this, you may face weeks of delays earning no return on your investment.
Your legal rights
The Australian Consumer Law (Schedule 2 of the Competition and Consumer Act 2010) provides consumer guarantees that cannot be excluded by contract: the system must be of acceptable quality, fit for purpose, match its description, and be installed with due care and skill. If the system fails to meet these guarantees, you have rights to repair, replacement, or refund. CEC-accredited installers must comply with the CEC Code of Conduct. The Clean Energy Regulator oversees the Small-scale Renewable Energy Scheme (SRES) that provides STCs. State fair trading bodies (e.g., NSW Fair Trading, Consumer Affairs Victoria) handle complaints about solar installers. The 10-day cooling-off period applies to unsolicited sales (door-to-door or telemarketing).
Questions to ask before you sign
- 1Are you CEC-accredited, and are all proposed products CEC-approved?
- 2What is the estimated annual energy generation (kWh) for my specific installation?
- 3What is the workmanship warranty period, and what does it cover?
- 4Who handles the grid connection application, and what is the expected timeline?
- 5What are the payment terms, and is the final payment tied to successful grid connection?
- 6What happens if the system underperforms the estimated generation by more than 10%?
- 7Can you provide details of recent installations with similar roof orientation and system size?
Disclaimer: This guide is for educational purposes only and does not constitute legal advice. Contract law varies by jurisdiction and individual circumstances. Always consult a qualified legal professional before making decisions based on this information.