Solar InstallersUpdated March 2026 · 2 min read

How to Quote a Solar Panel Installation in Australia

Guide to quoting residential solar installations. Covers system sizing, STC rebates, panel and inverter selection, and how to present competitive solar quotes.

What to Include in a Solar Quote

A solar installation quote should include: panel brand, model, and wattage; inverter brand and capacity; number of panels and system size (kW); mounting system; electrical work (isolators, meter board upgrade if needed); STC rebate breakdown showing gross and net price; expected annual energy production (kWh); estimated payback period; and warranty details for panels and inverter.

System Sizing Guide

A typical Australian household uses 15–25kWh per day. A 6.6kW system (16x 415W panels) produces approximately 24–28kWh/day in most Australian locations. Size the system based on the customer's electricity bill and roof space. Oversizing slightly is common since feed-in tariffs offset excess production. Always check roof orientation and shading.

STC Rebate Calculations

The STC (Small-scale Technology Certificate) rebate significantly reduces the upfront cost. The number of STCs depends on system size, location (postcode zone), and the current deeming period. In 2026, a 6.6kW system in Sydney generates roughly 80–90 STCs. At approximately $37–$40 per STC, that's a $3,000–$3,600 rebate. Always show the gross price and rebate as separate line items.

Presenting a Competitive Solar Quote

Customers typically get 3+ solar quotes, so presentation matters. Include: a clear price breakdown (not just a total), the STC rebate as a visible line item, estimated annual savings in dollars, payback period calculation, and warranty summary. A professional PDF quote with your logo and ABN builds trust. QuoteMate generates this automatically.

Common Solar Quoting Mistakes

1. Not checking roof condition (may need repairs before installation). 2. Ignoring shading from trees or neighbouring buildings. 3. Not factoring in meter board upgrades. 4. Quoting a system too large for the available roof space. 5. Not showing the STC rebate breakdown clearly. 6. Forgetting to include electrical safety inspection costs.

Pro Tips

Always conduct a site visit or use satellite imagery to check roof suitability
Show the STC rebate as a separate line item — customers want to see the discount
Include estimated annual production and dollar savings
Specify warranty periods for panels, inverter, and workmanship separately
Check if meter board upgrade is needed and include it in the quote
Present payback period to help the customer justify the investment