Commercial Solar FAQ for Perth Businesses

To your bill, not just your roof. A system sized purely to fill the roof often exports cheaply when you generate more than you use, and export limits set by the network cap what a larger array returns anyway. Whether your supply is single or three-phase also shapes what’s practical. So a sensible first step is checking your real daytime draw against the available roof, rather than reaching for maximum capacity.

We start by reviewing twelve months of bills and interval data, then assess the roof structure, shade, and switchboard capacity. The switchboard check confirms there’s room to add solar safely and whether an upgrade is needed. We design the system, lodge Western Power approvals, then book the install. Network approvals commonly take a few weeks; larger systems longer where a study is required. You’ll need to grant roof and switchboard access and nominate quieter periods for connection.

We map your interval data against expected generation half-hour by half-hour, because the load profile matters as much as the total. A site running machinery, cooling or refrigeration through the day soaks up most output, so a larger array still earns its keep. A nine-to-five office with a quiet midday is better served by a smaller, well-matched system. The shape of your day, not just annual kWh, decides the right size.

For most commercial sites with solid daytime use, payback commonly lands in the range of roughly three to seven years, though yours depends on four things: your current c/kWh rate, the share of generation you self-consume, any export limit, and demand or capacity charges. Self-consumed solar offsets the full retail rate while exports earn far less, so high daytime load shortens payback most. We model generation against your real usage, not generic averages, so your figure reflects your site.

Connection runs in a set order. We apply to Western Power for approval to connect, which can take a few weeks. Larger systems may trigger a network study and an export limit, extending that timeline. Once approved and installed, the system is registered on the DER Register and must meet WA compliance requirements. You’ll need to supply your NMI, recent bills and site access; we prepare and lodge the applications and keep the paperwork moving so nothing stalls connection.

Not always. Batteries store surplus solar for use outside daylight hours, and can shave peak demand charges or shift load on time-of-use tariffs. They suit sites with evening use, export limits or high capacity charges. Many businesses with strong daytime load get solid value from solar alone. We assess whether storage earns its place for your specific usage pattern.

In most cases, yes. Mounting, panel work and most cabling happen on the roof while you trade normally. A power interruption is only needed to tie the system into your switchboard and for final commissioning, usually an hour or two, which we book before opening, after hours or during a planned quiet window. We’ll tell you the likely timing upfront so you can warn staff and pause any sensitive equipment beforehand.

System size and panel count usually drive cost most, followed by roof type and access, which dictate mounting and labour. Inverter choice, any switchboard upgrade, and connection or metering work come next; storage, ground-mounts and structural engineering add to some projects. A quote should itemise the array, inverter, mounting, electrical work and approvals separately so you can see what’s included. We assess the site and energy use, then set that out in writing.

Often, yes. Sites at the end of a rural feeder can have weaker grid voltage, which affects how much a system may export and sometimes tightens the limit the network allows. Agricultural and industrial roofs also vary in structure and pitch. We factor voltage conditions and roof type into the design so the system performs as intended. Metro industrial sites are usually more straightforward on the network side.

A preventative schedule, typically annual, keeps a commercial system performing. Perth dust, pollen and bird droppings cause soiling that quietly reduces output, so periodic cleaning and inspection matter. Checks cover isolators, connectors, cabling and inverter health, often with thermal imaging to catch hot spots early. Monitoring flags underperformance between visits so faults are addressed before they cost you generation.