Buying solar in Perth: a 12-step pre-purchase checklist

Getting solar in Perth involves more steps than just picking a system size and signing a quote. This checklist walks through what to confirm before you commit — covering your roof, your network connection, your quote, and the installation process.

Step 1 — Understand your current electricity bill

Before sizing a solar system, know what you're working with:

• What is your quarterly kWh consumption?
• What tariff are you on (Standard A1, Midday Saver, or other)?
• What time of day do you use most power?

A high-consumption household using most power in the morning and evening will have different solar economics than a household with significant midday consumption (working from home, pool pump, etc.). Use BillWise to analyse your current bill and model which tariff suits you best.

Step 2 — Assess your roof

Before getting quotes, form a view on your roof:

• Roof direction: Which way does your best roof face? North-facing is ideal; east/west splits work; south is a significant penalty.
• Shading: Are there trees, neighbouring buildings, or your own roof structures (chimneys, skylights, water tanks) that shade the roof between 9am–3pm?
• Roof type and age: Concrete tile, Colorbond, terracotta, or flat? If your roof is more than 15 years old, it may need maintenance before solar installation. Raise this with installers.
• Area: A rough measure of unshaded roof area gives you a sense of maximum panel fit.

Step 3 — Check your Western Power export limit

In many Perth suburbs, you're limited to 1.5kW of export to the grid regardless of how large your system is. This affects the financial return on large systems.

Check your export limit before sizing: visit westernpower.com.au and search your property address. If your limit is 1.5kW or zero-export, a battery is more financially compelling because it allows you to store and self-consume generation that would otherwise be curtailed.

Step 4 — Know your switchboard

Solar requires at least one spare circuit breaker slot in your switchboard. If your switchboard is old (fuses rather than circuit breakers, or a full panel with no spare slots), you may need a switchboard upgrade — budget $800–$1,500 for this and ask installers to assess it during the site visit.

Single-phase vs three-phase: most Perth homes are single-phase, which means a maximum 5kW inverter (6.6kW of panels) for a standard connection. If you have three-phase power, you can install larger inverters and claim a higher export limit.

Step 5 — Understand smart meter status

To receive the Distributed Energy Buyback Scheme (DEBS) export rate and to access time-of-use tariffs like Midday Saver, you need a smart meter (interval meter) that can record import and export separately.

Western Power upgrades meters for free when you connect solar. If you don't already have a smart meter, the solar connection process triggers an automatic upgrade. Confirm this is included in the installation scope.

Step 6 — Get at least 3 quotes

Three quotes from different installers give you a meaningful comparison. When comparing quotes:

• Same or similar panel and inverter brands allow like-for-like price comparison
• Different brands require comparing specifications (efficiency, warranty terms, temperature coefficient)
• A significantly lower quote (20%+ below the others) warrants a closer look at what's been excluded

Make sure each quote includes:

• Western Power connection and grid notification costs
• All DC and AC wiring, switchboard work if needed
• Monitoring system setup
• The STC rebate amount clearly shown and applied

Step 7 — Verify the installer's CEC accreditation

Every solar installation must be done by or under the supervision of a CEC-accredited installer. Ask each installer for their CEC accreditation number and verify it at solaraccreditation.com.au.

Check whether the company is on the CEC Approved Retailer list (cec.org.au) for additional consumer protections.

Check their WA electrical contractor licence number and verify it with EnergySafety WA.

Step 8 — Understand the system design

A reputable installer should provide:

• Orientation-adjusted generation estimate (kWh/year based on your specific roof orientation) — not just a generic "6.6kW = 12,000 kWh" figure
• Shading assessment — whether tools like Solargis or PVsell have been used to model your specific address
• String configuration — how many panels per string, which direction each string faces, and why

If an installer quotes without a site visit or provides only a generic kWh estimate, that's a gap in the assessment.

Step 9 — Ask about monitoring

Confirm the inverter connects to your home WiFi and that you'll have access to a monitoring app to track daily generation and faults. Confirm the installer will set this up at commissioning and show you how to use it.

If the quote includes microinverters (Enphase) or power optimisers (SolarEdge), the per-panel monitoring capability is a premium feature — verify it's included in the quoted system.

Step 10 — Understand the timeline

Solar installation in Perth typically takes:

• Quote and site visit: 1–3 days after initial enquiry
• Quote acceptance to installation: 1–6 weeks depending on installer backlog
• Western Power notification and approval: 3–10 business days (submitted by installer)
• Meter upgrade and connection: 5–15 business days after Western Power approval
• Total from decision to operational: typically 4–10 weeks

You can be invoiced for the installation before the meter upgrade is complete. The system is installed, tested, and ready — you're just waiting for Western Power to upgrade the meter and activate the grid connection.

Step 11 — Confirm warranty terms in writing

Before signing, confirm in writing:

• Panel product warranty (years) and performance warranty (% at year 25 or similar)
• Inverter warranty (typically 5–10 years standard, up to 12 years for SolarEdge, 25 years for Enphase)
• Workmanship warranty (installer's warranty on the installation itself — typically 5 years minimum under CEC requirements)
• Who handles warranty claims — the installer, the manufacturer directly, or a third party?

For battery additions: battery warranty varies significantly by brand (10 years is typical, 15 years for some Enphase). Ask for throughput guarantee terms as well as calendar warranty.

Step 12 — Consider whether a battery makes sense now or later

Battery costs remain significant ($8,000–$15,000 installed for 10kWh). Many Perth households get solar first and add a battery 2–5 years later when prices have dropped further and they have a clear picture of their self-consumption patterns.

Consider battery now if:

• Your suburb has a 1.5kW or zero export limit (battery absorbs curtailed generation)
• You want backup capability during blackouts
• Your household's evening consumption is high relative to daytime

Battery later makes sense if:

• Your main goal is reducing daytime electricity costs (solar alone achieves most of this)
• Budget is a constraint
• You want to wait for prices to fall or technology to improve further

This checklist covers the typical Perth solar purchase process as of 2026. Individual installer processes, Western Power timelines, and rebate schemes may change. Verify current conditions with your installer and through official Western Power and Synergy channels.