How I read a solar quote
By Oliver Hill · Independent, not affiliated with any installer
I sold solar for eleven years. This is a real quote, identifying details removed and with the homeowner's permission, read the way I read one when someone sends it to me. Two lines were padding. One was arguably fair. The biggest problem was not in the price at all.
Every claim on this site is that it is independent. That is easy to write and hard to prove, so here is the thing a salesperson would not publish: the actual method, applied to an actual quote, including the parts where the answer was "that is fine, pay it".
The quote
Single-storey tin roof in outer Melbourne. 6.6kW with a hybrid inverter, no battery yet. Quoted at $12,740 before rebates.
| Line item | Quoted | Verdict |
|---|---|---|
| 6.6kW panel array | $4,200 | Fine |
| Reasonable for the tier quoted. Nothing to argue with. | ||
| Hybrid inverter | $2,900 | Ask |
| A hybrid only earns its premium if a battery is actually coming. If it is not, a standard inverter does the same job for less. | ||
| Installation and mounting | $2,100 | Fine |
| Normal for a single-storey tin roof. | ||
| “System design and engineering” | $1,450 | Push back |
| This is not a separate service. Designing the system is part of selling it. In eleven years I never met an installer who genuinely costed it separately. | ||
| Monitoring package, 5 years | $890 | Push back |
| The inverter already monitors. This was a subscription to an app that came free with the hardware. | ||
| Extended warranty | $1,200 | Ask |
| Ask what it covers beyond the manufacturer warranty, and who administers it. Often it duplicates cover you already have. | ||
That is an 18 per cent difference, and none of it required haggling. It required asking what two line items were for and getting no answer that survived a follow-up question.
The bigger problem was not the price
The quote projected savings of $2,180 a year. The household was out during the day, on a flat tariff, in a state with a feed-in tariff near one cent. On those facts the realistic figure was closer to $1,300.
Nothing in the price list was wrong about that. The savings number rested on an assumption that most of the generation would be used on site, and for a house that is empty from eight until six, it will not be. Nobody lied. The assumption was simply never stated, and it was worth more than eight hundred dollars a year of imaginary saving.
This is the thing to check first. A padded line item costs you once. An inflated savings assumption changes the entire case for buying at all.
What I would have asked
- What self-consumption percentage is behind the savings figure, and does it match a house that is empty during the day?
- What feed-in tariff did you use, and is that the current one for this state?
- What does "system design and engineering" cover that is not part of quoting the job?
- Am I paying a hybrid inverter premium for a battery I have not decided on?
Four questions. The first two are the ones that matter, and almost nobody asks them, because the price list is where attention naturally goes.
What this does not prove
One quote is one quote. Plenty of installers quote fairly, itemise properly and use honest assumptions, and I have read those too. This is not evidence that the industry is crooked. It is evidence of what to look at, and of the fact that I will publish the method rather than ask you to trust the conclusion.
Run your own numbers first
System size, cost after your state's rebates, payback and a ten-year projection, with every assumption shown.
Check my home, freeCommon questions
Is a higher solar quote always worse?
No. A higher price can buy better equipment, a better installer, or work your site genuinely needs such as a switchboard upgrade. What matters is whether the extra is itemised and explained. An unexplained premium is the problem, not a premium.
What is the most common padding in a solar quote?
An inflated savings projection rather than an inflated price. A quote built on a feed-in tariff two or three times the real one, or a self-consumption assumption that does not match the household, overstates ten years of savings without a single line item looking wrong.
Should I always take the cheapest quote?
No, but you should make the dearest one justify itself in writing. Ask what the difference buys, item by item. If nobody can name it, it is margin.
What should be in writing before I sign?
The exclusions. Switchboard upgrades, meter changes, scaffolding, tile replacement and additional travel are the variations that appear afterwards. Get a price for each in case it is needed.