Large metal roofs and daytime loads make Western Sydney warehouses and factories strong solar sites. Here is how we check roof structure, switchboards, export limits and monitoring, and how to stage a project sensibly. For most warehouses and factories in Western Sydney, rooftop solar is one of the more straightforward energy upgrades a business can make: large metal roofs, work that happens in daylight hours and an existing three-phase supply all line up well with how solar produces power. Whether a particular site delivers a good return depends on the detail. The structure and condition of the roof, the capacity of the main switchboard, the export limit the network sets and how much of the output you use on site all shape the right system. This guide covers what our team checks on industrial sites from Smithfield and Wetherill Park to Erskine Park and Moorebank, and how to stage a project so each step pays its way.
Why industrial buildings suit solar
A typical industrial unit has a broad, low-pitch metal roof with few vents or obstructions, so panels can be laid out in long, efficient rows. Many sites run machinery, compressors, refrigeration, lighting and office air-conditioning through the middle of the day, which is exactly when an array produces most. Energy used on site is worth far more than energy exported, because business import rates are usually well above what a retailer pays for exports.
Western Sydney's hot summers add to that daytime load, but heat also trims panel output. Panels typically lose around 0.3-0.4% of output for every degree their cells run above 25 degrees Celsius, and cells on a metal roof in January run much hotter than the air. We allow for that in yield estimates and mount inverters in shaded, ventilated positions so they are not forced to reduce output on the hottest afternoons.
Start with the load, not the roof
A big roof tempts people to fill it. The better starting point is your interval meter data: 12 months of 15- or 30-minute readings showing when the site uses power. We look at weekday baseload, start-up peaks, weekend and after-hours use, and shutdown periods such as the Christmas break. A system sized so that most of its output is used on site during normal operating days usually returns more per dollar than one sized to the roof edge that exports heavily on weekends.
| Site profile | Match with solar | What we usually suggest |
|---|---|---|
| Single-shift manufacturing, weekdays | Strong on weekdays, weak on weekends | Size to weekday daytime load and check weekend exports |
| Cold storage running around the clock | Strong all week, with night load solar cannot cover | Solar sized to daytime load, with a battery stage assessed later |
| Distribution warehouse, light daytime use | Moderate | A smaller first stage, with equipment charging moved into daylight where practical |
| Two-shift operation | Strong by day, evening peak remains | Solar first, then review demand charges before adding storage |
If you do not have interval data handy, your retailer can usually supply it, and our Interval-Data Analysis service turns a year of readings into a clear load profile before design starts.
Structural and roof checks
An array adds weight and, more importantly, wind uplift forces to a roof. On industrial buildings we check:
- Sheeting condition. Rusted, cracked or patched sheets should be replaced first, because lifting an array later to fix a leak is expensive.
- Purlins and fixings. Rails must attach into the structure at spacings that suit the site's wind region and roof profile.
- Roof material. Some older sheds have asbestos cement roofing. We do not install on it; the roof needs licensed assessment and replacement first.
- Skylights and safe access. Brittle roof lights, edge protection, anchor points and a clear access route must be planned for installation and future servicing.
- Engineering sign-off. Larger arrays and older structures usually need a structural engineer's certification.
Switchboards, network approval and export limits
Most industrial sites already have three-phase power, but that does not mean the main switchboard has room for a large solar connection. We check busbar and protection ratings, space for the solar main switch and whether the board suits the new work. Where a board is old or full, the upgrade is itemised in the quote rather than discovered on installation day.
Commercial systems also need approval from the local electricity network before connection. Depending on system size and local conditions, the network may approve full export, set a lower export limit or require zero export. That decision changes the design: with a tight limit, the system is sized closer to on-site demand and export control reduces output when the site is quiet. Because conditions vary between streets and estates, we lodge the application early and design to the approved outcome.
Monitoring a facilities team will use
On a commercial roof, a tripped inverter or disconnected string can go unnoticed for months because nobody climbs up to look. Good commercial monitoring compares production with expected output, alerts the right person when an inverter faults, and measures site consumption so you can see how much solar is used on site versus exported. We send alerts to whoever manages the building, not just to us, and show your team what a normal clear-day production curve looks like so abnormal days stand out.
Staging the project
Not every business wants to commit its whole roof at once, and staging is often the smarter path:
- Stage one: an array matched to weekday baseload on the best roof section, with inverter capacity and cable routes planned for growth.
- Stage two: more panels once a year of monitoring confirms how much solar the site absorbs.
- Stage three: a battery, if the demand profile shows it can reduce peak charges or shift solar into evening shifts. NSW business battery incentives apply to eligible batteries from 1 September 2026, and we check current eligibility at that point.
If you lease the building, raise solar with the landlord early. Roof access, equipment ownership and what happens at the end of the lease all need written agreement.
What commercial solar costs
On our energy market, Commercial Rooftop Solar starts from $27,900 for a 30 kW system installed, and Industrial Solar starts from $89,000 for a 100 kW system installed. These are indicative starting prices, confirmed after a site assessment, and depend on roof type, switchboard work, structural requirements, access equipment and network conditions. Eligible systems can also receive STCs that reduce the upfront price, and we confirm eligibility in the quote. For scale, a well-oriented Sydney array commonly averages around 3.6-4.1 kWh a day per kW installed, more in summer and less in winter.
Next steps
Gather a year of electricity bills and, if possible, your interval data. You can model an early payback range with our commercial ROI calculator and read about our approach on the commercial solar page. When you are ready, request a quote and our team will arrange a site visit to inspect the roof, switchboard and metering before we put a number on paper.
Frequently asked questions
Can we keep operating while the system is installed?
Usually, yes. Most of the work happens on the roof, and the site stays powered until the final connection. Connecting a large system into the main switchboard normally needs a planned shutdown, which we schedule with you, often early in the morning, on a weekend or during a quiet period. We also plan lifting access, exclusion zones and forklift movements so installation does not disrupt deliveries or put staff at risk.
Does commercial solar need council approval?
Many rooftop systems on existing industrial buildings can proceed without a development application, but it depends on the site. Heritage listings, arrays that change a building's height or appearance, ground-mounted systems and some consent conditions can trigger council requirements. We check the planning position during the assessment, and if approval is needed we tell you before you commit, so the timeline and cost reflect it.
How long do commercial panels and inverters last?
Quality panels typically lose around 0.4-0.55% of output a year, so an array can keep producing for decades. Inverters work harder and are usually the first major component to need replacement during a system's life. Good ventilation, shade and active monitoring help protect them and the return on the project. We explain the specific product and performance warranty terms of the equipment we specify in your proposal.
Please Login or Sign up to be able to comment