Bookkeeping for Solar Installers in Geelong

Geelong's solar installation industry continues to grow. With Victoria's commitment to renewable energy targets and the ongoing popularity of residential solar across the Bellarine Peninsula, Surf Coast, and greater Geelong, local installers face unique bookkeeping challenges that standard accounting practices don't address.

Between tracking Small-scale Technology Certificates (STCs), managing Victorian Solar Homes rebates, and keeping accurate job costings across multiple installations each week, your financial records can quickly become overwhelming. This guide covers the specific bookkeeping requirements for Geelong solar installers and how to stay compliant while maximising your cash flow.

Understanding STC Accounting for Solar Installers

Small-scale Technology Certificates represent one of the most confusing aspects of solar installation bookkeeping. Each residential system you install generates STCs based on the system size and location—Geelong falls into Zone 3, which affects the certificate calculation.

Under Section 70-10 of the Income Tax Assessment Act 1997 (ITAA 1997), STCs are classified as trading stock. This means you need to track them as inventory in your accounting system. Here's how the process works:

• Creation: When you complete an installation and create STCs in the REC Registry, record them at their current market value as inventory
• Holding: If you hold STCs rather than selling immediately, revalue them at the end of each financial year
• Sale: When you sell STCs (either to a registered agent or through the STC Clearing House), record the sale as income
• Point of sale discount: Most installers assign STCs to an agent in exchange for an upfront discount to customers—track this as a sale at the assigned value

The STC Clearing House price sits at $40 per certificate, but market prices through agents fluctuate. Your bookkeeping system should capture both the creation and disposal of STCs separately from your installation revenue to maintain accurate profit margins on each job.

Victorian Solar Homes Rebate Recording

If you're an approved installer under Victoria's Solar Homes program, you'll receive rebate payments directly from Solar Victoria after completing eligible installations. These payments require specific accounting treatment.

The rebate (currently up to $1,400 for solar panel systems) reduces the customer's out-of-pocket cost but doesn't reduce your taxable income. Record the full installation price as revenue, then track the rebate payment as a separate income line when it arrives from Solar Victoria.

GST treatment: You charge GST on the full installation price before the rebate reduction. If a system costs $8,000 and the customer receives a $1,400 rebate, your invoice shows $8,000 plus $800 GST. The customer pays $7,400 out of pocket (after rebate), and you receive $1,400 from Solar Victoria separately.

Track each rebate against its corresponding job. Solar Victoria payments can take 4-6 weeks after job completion, so your accounts receivable needs to reflect outstanding rebates as a separate category from customer payments.

Job Costing for Solar Installations

Every solar installation involves multiple cost components that affect your true profit margin. Without accurate job costing, you might quote jobs that lose money or undervalue your profitable work.

For each Geelong installation, track these cost categories:

• Materials: Panels, inverters, mounting hardware, cabling, isolators, and meter boards
• Labour: Your installers' wages or contractor payments, including travel time to the job site
• Electrical work: Licensed electrician costs for grid connection and compliance certificates
• Permits and inspections: Local council requirements and Energy Safe Victoria inspections
• Vehicle and equipment: Proportion of vehicle costs for site visits, delivery, and installation
• Insurance: Per-job allocation of your public liability and professional indemnity premiums

Xero's tracking categories work well for solar installers. Create a tracking category for each job, then tag all related expenses. This approach shows you the true profit on a $15,000 Torquay beachfront installation versus a straightforward $8,000 Belmont roof, helping you adjust your quoting strategy accordingly.

BAS Lodgement Requirements

Most solar installation businesses lodge BAS quarterly, though some larger operators report monthly. Under the Tax Agent Services Act 2009 (TASA 2009), only registered BAS agents can lodge on your behalf for a fee.

Your BAS captures several solar-specific items:

• GST on installations: Full installation price including labour and materials
• GST on STC sales: When you sell certificates to an agent or through the Clearing House
• Input tax credits: GST paid on panels, inverters, tools, vehicle expenses, and other business purchases
• PAYG withholding: If you employ installers, include wages tax withheld
• PAYG instalments: Your own income tax prepayments if required by the ATO

Many solar installers find their GST position varies significantly each quarter based on large panel purchases versus installation completion timing. A system that matches panel purchases to the jobs using them gives you better visibility of your true GST liability.

Managing Contractors and Employees

Solar installation businesses often use a mix of employed installers and subcontractors. The ATO scrutinises this industry for sham contracting arrangements, so your bookkeeping must reflect the true nature of each working relationship.

For employees, your obligations under the Superannuation Guarantee (Administration) Act 1992 include:

• Paying super at 11.5% (increasing to 12% from 1 July 2027) on ordinary time earnings
• Withholding PAYG tax from wages
• Providing payslips within one working day of payment
• Paying at least the Electrical, Electronic and Communications Contracting Award minimum rates

For genuine contractors, collect their ABN before paying, obtain invoices for each job, and don't withhold tax unless they don't provide an ABN (then withhold at 47%). Visit Fair Work Australia to check whether your workers are correctly classified.

If the ATO reclassifies your contractors as employees, you'll face back-payment of superannuation, penalties, and potential PAYG withholding obligations. Your bookkeeping records form the primary evidence in any audit, so accurate categorisation from the start protects your business.

Inventory Management for Panels and Equipment

Solar installers carry significant inventory value in panels, inverters, and electrical components. Proper inventory tracking affects your tax position and cash flow visibility.

Under Division 70 of the ITAA 1997, trading stock must be valued at the end of each financial year. You can choose between cost, market selling value, or replacement value—and you can use different methods for different stock items. Most solar businesses use cost value for simplicity.

Track your inventory by:

• Panel brand and model: Different manufacturers have different costs and warranty implications
• Inverter type: String inverters, microinverters, and hybrid systems have varying margins
• Mounting hardware: Tile, tin, and flat roof systems need different equipment
• Batteries: If you install storage systems, these represent high-value inventory items

Xero's inventory tracking connects to apps like Tradify, letting you allocate materials to specific jobs automatically. When an installer completes a Geelong West installation, the system updates inventory counts and calculates job margins in real time.

Record Keeping Requirements

The Taxation Administration Act 1953 requires you to keep records for five years from when you prepared or obtained them, or five years after the relevant transaction completed—whichever is later.

For solar installers, essential records include:

• Customer contracts: Quotes, accepted proposals, and installation agreements
• STC documentation: REC Registry records, STC assignment forms, and sale confirmations
• Solar Homes paperwork: Eligibility declarations, rebate applications, and payment receipts
• Supplier invoices: Panel, inverter, and equipment purchases with serial numbers
• Compliance certificates: Electrical safety certificates and council inspection records
• Vehicle logbooks: If claiming motor vehicle expenses
• Employee/contractor records: TFN declarations, ABN details, timesheets, and super payments

Cloud-based systems like Xero store records automatically and meet ATO electronic record requirements. Attach supplier invoices, photos of completed installations, and compliance certificates directly to transactions for complete audit trails.

What to Do Next

If your current bookkeeping involves spreadsheets, shoeboxes of receipts, or guesswork about which jobs actually make money, it's time to systematise. Start with these steps:

• Review your STC tracking: Can you identify exactly how many STCs you've created and sold this financial year?
• Check your rebate receivables: Do you know how much Solar Victoria owes you right now?
• Assess your job profitability: Can you see profit margins on each installation, or just overall business profit?
• Confirm your contractor classifications: Would your working arrangements survive an ATO audit?

A properly configured Xero system with job tracking integration takes the guesswork out of solar installation bookkeeping. You'll see which jobs make money, which customers pay slowly, and whether your pricing keeps up with material cost increases.

For Geelong solar installers ready to get their bookkeeping sorted, we offer a free 20-minute consultation to assess your current setup and identify quick improvements. You'll come away with a clear understanding of what's working, what's not, and what it would take to fix it.