The 6 Mistakes Homeowners Make When Buying Solar (And How to Avoid Them)

The 6 Biggest Mistakes Homeowners Make When Buying Solar

Australia is adding rooftop solar at a breakneck pace, yet most homeowners still buy systems with little idea of what they’re actually paying for. The result is predictable. Underperforming panels. Wrong-size systems. Installers who disappear the moment something breaks.

When you’re buying a solar system, a few key decisions have a big impact on how well it performs and how long it lasts. These are the mistakes homeowners run into most often and how to avoid them.

Mistake 1: Choosing panels based on price alone

Cheap solar systems usually deliver the lowest long-term value.

Most people start with the number on the quote. It is understandable. Solar is expensive and nobody wants to pay more than they need to. The problem is that system quality is not visible in the sticker price. Cheaper offerings often rely on low-efficiency panels, short warranties, and inverters that struggle in Australian heat.

A system that looks like a bargain today usually replaces its savings with headaches later. Panels degrade faster, inverters fail early, and performance drops when you need it most. Paying a little more upfront for proven components often produces thousands in extra savings over the life of the system.

Still, even good panels mean nothing if you fall into mistake two.

Mistake 2: Underestimating how much solar they actually need

Many households buy too-small systems and regret it within two years.

Most people size their system for their current bill. But bills change fast. Homes electrify. Electric vehicles arrive. Reverse-cycle air conditioning replaces gas heating. And daytime power use increases once people learn to shift loads.

Oversizing a system is often cheaper than upgrading later. Panels are the lowest-cost part of the system. The labour and inverter capacity dominate the price, so adding a few extra panels usually makes the economics stronger, not weaker.

Having the right system size is one thing. Having the right person install it is another.

Mistake 3: Choosing an installer without checking accreditation or history

Solar should only be installed by SAA-accredited installers with a proven track record.

From February 2024, accreditation moved to Solar Accreditation Australia (SAA). That shift matters because electrified homes need careful, compliant work. Poor installation is the biggest cause of inverter failures, panel damage, and roof leaks.

Check the installer’s SAA accreditation, workmanship warranty, customer reviews, and how long they have been operating. Many of the cheapest providers vanish within a year or two. Warranty support disappears with them. A reputable installer creates a system that lasts decades, not seasons.

Even experienced installers can stumble when homeowners ignore the next point.

Mistake 4: Ignoring the roof

Roof condition, orientation, shading, and usable space determine how well solar performs.

Panels are only as good as the roof they sit on. Shading from trees and chimneys can strip away a surprising amount of output. Older roofs may need repairs before installation. And some tile types cost more to work with, which catches people by surprise.

Spend time on your roof assessment. A simple tweak to orientation or panel layout can recover hundreds of dollars a year in lost generation. Roof planning sets the stage for the part homeowners overlook most: the warranties.

Mistake 5: Not understanding warranties

Panel, inverter, and workmanship warranties are separate, and they vary widely.

A glossy brochure promising a “25-year panel warranty” sounds impressive until you read the fine print. Performance warranties are not product warranties. One covers slow degradation. The other covers actual failures. And they are not equal.

Inverters usually have shorter warranties than panels. Many installers only offer five years on workmanship, despite producing systems expected to run for twenty. If the workmanship fails, everything else falls with it.

Choose brands and installers with strong, enforceable warranties. A system is only as reliable as the company willing to stand behind it.

You stand to save a lot of money with solar when taking advantage of rebates and feed-in tariffs, but be sure to get the basics right before you install.

Mistake 6: Focusing on rebates instead of long-term savings

Chasing the biggest rebate often leads to system choices that cost far more over time.

Most homeowners still believe they can claim a “solar rebate” manually. In reality, the main incentive is the federal Small-scale Technology Certificate (STC) discount. Installers apply it automatically, so any system touting a bigger rebate is usually compensating somewhere else.

State rebates can influence decisions too, but they should not determine the system size, panel brand, or installer you choose. The real savings come from self-consumption, smart system design, and a reliable inverter that keeps working through Australia’s brutal summers.

Rebates shrink each year. System quality stays with you for decades.

How to avoid every one of these mistakes

The safest way to buy solar is to follow a structured process and compare like-for-like quotes.

Start with clear energy goals. Check the installer’s accreditation and history. Confirm component model numbers. And choose a system large enough to handle future electrification. Each step protects you from the common traps.

For a complete walkthrough of what to look for and what to avoid, the Buying Solar 101 guide covers every part of the process with examples, checklists, and plain language explanations.

Solar is one of the best investments a household can make. You just need the right information before you start.