Quick answer: Almost every common solar complaint traces back to one of eight avoidable decisions made before installation day — and each one can be sidestepped by asking the right questions first.
Most solar complaints trace back to a small handful of avoidable decisions made before installation day. If you know what to look out for, you can sidestep almost all of them. Here's what actually goes wrong, most often, and how to protect yourself.
The single most common regret among solar owners is installing a system too small for their actual or future usage. This usually happens when a system is sized to a budget or a rough rule of thumb ("most homes get 6.6kW") rather than to genuine consumption data, upcoming EV plans, or a future battery.
How to avoid it: insist on sizing based on your actual electricity bills and usage pattern, plus a conversation about anything on the horizon — an EV, a pool, a battery, a home renovation adding rooms or a home office. It's far cheaper to size correctly up front than to add a second, awkwardly-integrated array later.
The inverter is the component most likely to fail first, and it's also the component most commonly downgraded to cut quoted price. A budget or unbranded inverter might save a few hundred dollars upfront but often carries a shorter warranty, less responsive local support if it fails, and in some cases, meaningfully lower real-world efficiency.
How to avoid it: ask specifically which inverter brand and model is quoted, check it against the Clean Energy Council's approved product list, and weigh the warranty length and whether the manufacturer has genuine local support and stock in Australia — not just a website.
Remote, satellite-image-only quotes are increasingly common because they're fast and cheap to produce, but they miss things a genuine site visit catches every time: roof condition and remaining lifespan, shading from features not visible on imagery, switchboard capacity, roof structural suitability, and accurate cable run distances.
How to avoid it: be wary of any installer willing to provide a final, bookable quote without ever inspecting your roof in person. A genuine in-home assessment protects you from costly surprises on installation day.
Not every roof section is equal. Installers under time or cost pressure sometimes default to whichever roof plane is easiest to access rather than the one that actually performs best, or they split a system across orientations without properly accounting for the output difference.
How to avoid it: ask your installer to explain which roof sections your panels will go on and why, including expected relative output from each section if the roof has multiple usable faces (north being generally strongest in Sydney, with east and west also viable, particularly for spreading generation across the day).
This is the mistake with the most serious downside. Using an installer who isn't Clean Energy Council-accredited can mean you're not eligible for STCs or battery rebates at all, may void product warranties, and in the worst cases involves genuinely unsafe electrical work.
How to avoid it: independently verify CEC accreditation for both the installation business and the individual installer, don't just take their word for it — the Clean Energy Council maintains a public register. Our installer vetting guide walks through exactly what to check.
Even minor, partial shading — from a neighbour's tree, an antenna, a chimney, or a nearby building — can disproportionately cut a system's output if the design doesn't account for it, particularly with older string-inverter setups where one shaded panel can drag down an entire string.
How to avoid it: flag any known shading sources during your assessment, including trees that will grow taller over the system's 25+ year life, and ask whether power optimisers or microinverters are recommended for your specific roof.
A surprising number of systems are installed without the homeowner ever being shown how to access generation monitoring, meaning underperformance can go unnoticed for months or years.
How to avoid it: confirm before installation day that you'll get access to a monitoring app or portal, and ask your installer to walk you through it once the system is commissioned.
The cheapest quote in a stack of otherwise-similar quotes is almost always cheaper for a specific, identifiable reason — lower-tier equipment, a smaller design contingency, less thorough installation, or a shorter effective warranty relationship if the installer isn't well-established.
How to avoid it: compare quotes line by line on equipment brand, warranty terms, and design detail before comparing on price. A modest difference in headline price is rarely worth a materially worse system.
Almost every common solar complaint traces back to one of these eight issues, and every one of them is avoidable by asking the right questions before you sign. A premium, accredited installer with a genuine local team should welcome these questions, not deflect them.
Undersizing. The single most common regret is installing a system too small for actual or future usage, usually because it was sized to a budget or a rough rule of thumb rather than to real consumption data and future plans like an EV, pool, or battery.
It carries the most serious downside of all the mistakes. A non-Clean Energy Council-accredited installer can mean you're not eligible for STCs or battery rebates at all, may void product warranties, and in the worst cases involves genuinely unsafe electrical work. Always verify accreditation on the CEC public register.
No. Satellite-image-only quotes miss what a site visit catches every time — roof condition, shading not visible on imagery, switchboard capacity, structural suitability, and accurate cable runs. Be wary of any installer offering a final, bookable quote without inspecting your roof in person.
Rarely. The cheapest quote in a stack of similar ones is usually cheaper for an identifiable reason — lower-tier equipment, less design contingency, or a shorter warranty relationship. Compare line by line on brand, warranty, and design detail before comparing on price.
Want to sidestep these mistakes from the start? You can arrange a genuine in-home assessment and a detailed, accountable quote through Blue Energy Solar at blueenergysolar.com.au, or call 0421 458 217 / email sales@blueenergysolar.com.au.
