Solar Quotes for Small Business - What Changes?

Getting solar quotes for a small business is a different process from residential solar - and the differences matter more than most business owners expect. Here's what changes, and what to look for in a commercial solar quote.

System Sizing: Bigger and More Complex

Most residential solar systems are 6.6 kW–13 kW. Small business systems typically range from 10 kW to 100 kW depending on the business's electricity usage and roof area. The sizing methodology for commercial solar should be based on actual consumption data - preferably 12 months of interval data from your network distributor, not just your quarterly bill total.

Ask any installer quoting your business: "What data are you using to size this system, and can I see the consumption analysis?" A quote based on a rule-of-thumb system size rather than your actual load profile will underperform against its projected payback.

Network Rules Change at 10 kW

Residential connections typically fall under simplified network rules up to about 10 kW. Above that threshold, commercial systems require a formal network approval process - a Technical Study - which can take 4–12 weeks and may require additional equipment (protection relays, export limiting, metering upgrades) that adds cost to the quote.

Make sure any commercial quote includes: whether a Technical Study is required, who is responsible for managing it, and what additional network costs are included in the quoted price. Quotes that don't address network approval for systems above 10 kW are incomplete.

Finance Options Are Different

Residential solar is typically purchased outright or financed through a personal loan. Small business solar has additional options:

Chattel mortgage: You own the asset from day one. Depreciation and interest are tax-deductible. The system appears on your balance sheet.

Operating lease (PPA/rent-to-own): The installer or financier owns the system. You pay a fixed monthly fee for the energy generated. Lower upfront cost, but you don't own the asset and can't claim depreciation.

Instant asset write-off: Under current Australian tax rules, eligible small businesses (turnover under $10 million) can potentially write off the full asset cost in the year of installation, depending on the threshold in effect. This significantly improves the economics for businesses that are profitable.

Ask your accountant to model the after-tax cost before comparing quotes on face value alone.

STCs Work the Same - But the Numbers Are Larger

Small-scale Technology Certificates (STCs) apply to commercial systems up to 100 kW. For a 30 kW system in Zone 3, that's approximately $13,000–$18,000 off the gross price - a meaningful rebate that should appear as a deduction on any commercial quote. For systems above 100 kW, the Large-scale Renewable Energy Scheme (LRET) applies, which involves Large-scale Generation Certificates (LGCs) rather than STCs.

What a Good Commercial Solar Quote Includes

Beyond the standard residential elements (panel spec, inverter spec, STC rebate, workmanship warranty), a commercial quote should also specify:

• Consumption analysis and system sizing methodology
• Network approval status and any Technical Study requirements
• Metering changes required (typically a bi-directional smart meter)
• Export limiting settings if applicable
• Any switchboard or supply upgrade costs
• Commissioning and handover process
• Monitoring platform and reporting

If any of these are absent from a commercial quote, ask specifically. Small business solar is a significant capital investment - quotes that skip these details are not ready to sign.

For more on sizing and finance options, see our guide to solar for small business.

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