How to Quote a Solar Installation in Australia
Solar is a competitive quote — your customer is almost certainly holding three others. Here's how to size the system to their bill, get the STC rebate numbers straight, and present a price that wins for the right reasons.
Solar is a competitive quote — your customer is almost certainly holding three others. Win the job and you still have to size the system right, get the STC rebate numbers straight, and show a payback that stacks up on paper. This guide covers what a solar quote should include, how to size to the customer's bill, and how to present a price that stands out for the right reasons.
What a solar quote should include
A solar quote is as much a sales document as a price. A strong one covers all of this:
- Panels — brand, model, wattage, and the panel count.
- Inverter — brand and capacity.
- System size — the total in kW.
- Mounting and electrical — the racking system, isolators, and a meter board upgrade if it's needed.
- STC rebate — the gross price and the net after the rebate, as separate lines.
- The numbers that sell it — expected annual production in kWh, estimated dollar savings, and the payback period.
- Warranties — panels, inverter and workmanship, each stated separately.
Sizing the system to the customer
Size the system to the customer's actual use, not a round number. A typical Australian household uses 15–25kWh a day, and a 6.6kW system — around 16 x 415W panels — produces roughly 24–28kWh/day across most of the country. Read their electricity bill and check the roof before you settle on a size.
| Household use | Suggested system | Rough daily output |
|---|---|---|
| 10–15 kWh/day | 5–6.6 kW | 18–28 kWh |
| 15–25 kWh/day | 6.6 kW | 24–28 kWh |
| 25 kWh+/day | 8–10 kW+ | 30 kWh+ |
Slight oversizing is common and sensible — feed-in tariffs pay for the excess, and it leaves headroom for a battery or an EV later. Just don't quote a system bigger than the roof can physically take.
STC rebates, in plain numbers
The STC (Small-scale Technology Certificate) rebate is the number customers care about most, so get it right and show your working. How many STCs a system earns depends on its size, the postcode zone and the current deeming period. In 2026, a 6.6kW system in Sydney earns roughly 80–90 STCs.
| STCs earned | Value per STC | Rebate |
|---|---|---|
| 80–90 | $37–$40 | $3,000–$3,600 |
Always show the gross price and the rebate as separate line items — customers want to see the discount, not just a net figure they can't check against a rival's quote.
Presenting a quote that wins against three others
Customers get three or more solar quotes, so how you present yours decides as much as the price. Make it easy to compare and easy to trust:
- Give a clear breakdown, not just a total — panels, inverter, install and rebate.
- Show the STC rebate as a visible line so the discount is obvious.
- Include estimated annual savings in dollars, not just kWh.
- Add the payback period so the customer can justify the spend.
- Summarise the warranties for panels, inverter and workmanship.
- Send a professional PDF with your logo and ABN — it reads as a real business, not a back-of-envelope number.
Common mistakes that cost you the job
- Not checking the roof condition. An old roof may need repairs before panels go on. Spot it now, not after you've committed to a price.
- Ignoring shading. Trees, chimneys or a neighbour's roof cut output and change the layout. Assess shading before you promise production figures.
- Missing the meter board upgrade. Many older boards need upgrading for solar. Leave it out and it comes off your margin — check and quote it.
- Oversizing for the roof. A system that won't physically fit is a redesign and an awkward conversation. Confirm the usable roof area against the panel count.
- Burying the STC rebate. If the discount isn't a clear line, customers can't compare your quote to the others. Show gross, rebate and net.
- Forgetting the safety inspection. An electrical safety inspection is a real cost. Include it rather than absorbing it after the win.
Pro tips for a competitive solar quote
- Do a site visit or use satellite imagery to confirm the roof suits before you quote.
- Show the STC rebate as its own line — customers want to see the discount.
- Include estimated annual production and the dollar savings that come with it.
- State warranty periods for panels, inverter and workmanship separately.
- Check whether the meter board needs upgrading and put it in the quote.
- Present the payback period to help the customer justify the investment.
ServiceYak keeps your panel, inverter and install rates in a reusable kit and does the maths as you go, so you can build a competitive solar quote — gross price, STC rebate and net — and send a branded PDF the same day you visit.
Frequently asked questions
What size solar system does a typical home need?
Most Australian households use 15–25kWh a day, which a 6.6kW system covers well — it produces around 24–28kWh/day in most locations. Size it off the customer's actual electricity bill and the usable roof area, not a round number.
How much is the STC rebate on a 6.6kW system?
In 2026 a 6.6kW system in Sydney earns roughly 80–90 STCs. At about $37–$40 each, that's a $3,000–$3,600 discount off the upfront price. It varies with system size, postcode zone and the deeming period, so calculate it per job.
How do I win a solar quote when the customer has three others?
Make yours the easiest to trust and compare. Show a full breakdown rather than one total, put the STC rebate on its own line, include annual savings and a payback period, and send a professional PDF with your logo and ABN. Clear beats cheap more often than you'd think.