By Matthew Wittemeier
Solar can be a valuable feature when buying a home. A well-designed, properly installed and well-maintained system can reduce electricity bills, improve household resilience and add long-term value. But solar is not automatically an asset simply because panels are visible on the roof.
Like the building itself, a solar power system needs to be assessed before settlement. Prospective homeowners should treat a solar inspection as a standard part of their due diligence, alongside building, pest and electrical inspections.
Start with the basics
Ask the seller or agent for the system’s key documents as early as possible. A legitimate installed system should have a clear paper trail, including:
- The installation date and installer details
- The original system design, quotation and invoice
- Product information for panels, inverter, battery and mounting equipment
- Warranties and evidence of warranty registration
- Electrical certificates and compliance documentation
- Monitoring login details and recent production records
- Details of any battery, backup capability or energy-management equipment
- Records of servicing, repairs, inverter replacements or fault reports
The age of the system matters. Solar panels can continue generating for decades, but inverters commonly have a shorter operating life. A system installed 10 or 15 years ago may still have useful panels, while the inverter may be approaching replacement. A buyer should understand whether they are purchasing a reliable working system or inheriting a likely near-term cost.
Check whether the system is performing
A solar system may look fine from the ground while generating substantially less energy than expected. Production can fall due to inverter faults, panel damage, shading, wiring issues, water ingress, failed isolators, poor installation practices or deterioration that is not immediately visible.
A professional inspection should assess the current condition and performance of the system. This includes checking the inverter for error messages, reviewing available generation data, examining the panels and roof mounting, and testing key electrical components where appropriate.
It is also important to ask whether monitoring is active. Most modern systems can provide production information through an app or web portal. Access to historical data can help show whether the system has been operating consistently, whether output has declined and whether there have been periods of faults or shutdowns.
Do not rely solely on an electricity bill. Low bills may reflect low household consumption, a favourable feed-in tariff, an unoccupied property or a combination of factors. They do not necessarily prove that the solar system is in good working order.
Look closely at the roof and installation quality
Solar panels are only as secure as the structure supporting them. The inspection should consider the condition of the roof around the installation, the mounting arrangement, cable management and penetrations through roofing materials.
Items worth checking include:
- Whether panels are securely mounted and free of obvious physical damage
- Whether the roof structure and roof covering remain sound beneath and around the array
- Whether cables are appropriately secured and protected from weather, rodents and UV exposure
- Whether isolators, conduits and electrical equipment are in suitable condition
- Whether there are signs of leaks, corrosion, loose components or water ingress
- Whether trees, chimneys, satellite dishes or nearby construction are creating new shading problems
In regional and semi-rural areas, pay particular attention to vegetation growth, wildlife, weather exposure and accessibility for maintenance. A system that was clear of shade when installed may now be affected by mature trees. Similarly, a roof-mounted system should be reviewed with an understanding of local storm exposure and the practical requirements for future roof repairs or replacement.
Understand batteries and backup power
If the property includes a battery, buyers should confirm its age, usable capacity, warranty status and current operating condition. They should also ensure they can access the battery’s monitoring platform, as this provides important information about performance, fault history and usage.
Most battery warranties are limited by both time and total energy throughput or cycle count, much like a vehicle warranty may be limited by years or kilometres travelled. A battery may still be within its stated warranty period but have reached, or be close to reaching, its permitted usage limit.
Battery systems are more complex than standard grid-connected solar systems and may also include additional equipment, software, backup controls and switchboard modifications.
Do not assume a battery will keep the home powered during a blackout. Many solar and battery systems do not provide backup power unless they were specifically designed and installed with backup capability. Ask exactly what circuits are supported during an outage, whether the backup function has been tested and whether the system can operate safely during a grid failure.
This is particularly important for households that depend on refrigeration, medical equipment, water pumps, communications, home offices or other essential loads.
Check ownership, support and grid arrangements
Confirm that the solar system is owned outright and transfers with the property. In some cases, systems may be subject to finance arrangements, leases, power purchase agreements or other contractual obligations. These arrangements can affect who owns the equipment, who is responsible for maintenance and what commitments may transfer to the new owner.
Buyers should also confirm exactly who provides ongoing technical support for the system and how to contact them in an emergency. This will most often be the original installer, particularly where warranty claims, monitoring access or specialised equipment are involved. Many solar companies do not take on responsibility for servicing or supporting systems installed by another provider, so it is important to obtain the installer’s contact details, relevant documentation and any current service history before settlement.
You should also confirm the site’s current electricity retailer arrangement and feed-in tariff. Older systems may have access to legacy tariff arrangements that do not automatically transfer to a new customer. The system may still be valuable, but the future financial return could differ from the seller’s experience.
A note for renters
Renters should also ask questions before signing a lease for a home with solar. Confirm whether the system is operational, who receives access to monitoring, whether the electricity account will be set up to receive solar feed-in credits, and who is responsible if the system develops a fault. If a battery is installed, clarify whether it provides backup during outages and any conditions on its use. Solar can reduce energy costs for tenants, but only when it is functioning correctly and the electricity arrangement allows the benefit to flow through.
Make solar inspection part of your purchase process
Buying a home with solar should be an opportunity, not a gamble. A solar system is a significant electrical asset attached to the property, and its condition can affect both household running costs and future maintenance expenditure.
Just as buyers book building and pest inspections to understand the condition of the home, they should arrange a solar inspection to understand the condition, safety, performance and remaining value of the solar system.
Rainbow Power Company provides solar system inspections for prospective homeowners. Our inspections help buyers identify faults, assess system condition, understand likely maintenance needs and make an informed decision before settlement. Before you commit to a property with solar, make sure the system is inspected too. Book a solar inspection or call us at 02 6689 1430.
This article is general information only and is current at the time of writing. It is not legal, financial or building advice, and it does not replace a licensed building, pest or electrical inspection. The condition, performance and remaining value of any solar system depend on the individual installation and site. Rainbow Power Company, 1 Alternative Way, Nimbin NSW 2480.
