CER Audit Prep for Solar Installers: How to Pass Your Clean Energy Regulator Audit

CER Audit Prep for Solar Installers: How to Pass Your Clean Energy Regulator Audit

CER audit activity is increasing. The Clean Energy Regulator has been ramping up compliance work across the Small-scale Renewable Energy Scheme (SRES), and solar installers are firmly in scope. Whether you’re a sole trader with a CEC accreditation or running a crew of installers, understanding what auditors look for — and getting your documentation in order before they come knocking — is no longer optional.

This guide covers exactly what a CER audit involves, what triggers one, where installers typically fall short, and how to make sure you’re not one of them.

What Is a CER Audit?

The Clean Energy Regulator administers the SRES, which includes the Small-scale Technology Certificate (STC) scheme that most residential solar installers use every day. As part of its compliance function, the CER conducts audits of both installers and agents to verify that STC claims are legitimate and that installations meet the required standards.

There are three main audit types:

Desktop audit — The auditor reviews your documentation remotely. They’ll request job files, photos, certificates, customer declarations and STC lodgement records for a sample of your installations. No site visit required. This is the most common type.

Site audit — An auditor physically inspects an installation, checking the work against what was lodged. These are less common but carry significant weight if the site doesn’t match the paperwork.

Accreditation review — A broader review of your CEC accreditation status, including your endorsement categories, CPD compliance, and whether your work is consistent with the scope you’re accredited for.

What Triggers an Audit?

Not every audit is random. The CER uses data matching and pattern analysis across STC lodgements to identify anomalies. Common triggers include:

  • Random selection — The CER runs ongoing random compliance checks across all accredited installers.
  • High STC claim volumes — If your claim rate spikes significantly or your claims are outliers compared to similar installers in your region, that can trigger a review.
  • Consumer complaints — A complaint from a homeowner about a faulty installation or a dispute over system specifications can initiate an audit.
  • New or recently granted accreditation — New accreditations attract early-stage compliance checks to verify installers are working within their scope.
  • Agent-linked activity — If an agent or retailer you work with comes under scrutiny, the CER may audit installers they have lodged STCs for.

The short version: you do not have to do anything obviously wrong to get audited. You just have to be in the system.

What Auditors Actually Look At

Documentation is the number one audit failure area. Not workmanship — documentation. Most installations that fail an audit fail on paper, not on the roof.

Here is what auditors request and review:

STC Lodgement Accuracy

Every STC claim must accurately reflect what was installed — system size, panel count, inverter model, installation address, and install date. Discrepancies between what was lodged and what is in your job file are red flags.

Installation Photos

Photos need to be specific, date-stamped, and tied to the exact job. Auditors look for: roof layout showing panel positioning, DC isolator installation (including labelling), inverter installation with all labels visible, AC isolator and switchboard connection, and metering and grid connection. Generic or undated photos will not cut it.

Customer Declarations and Handover Documentation

You are required to provide customers with a handover pack that includes system documentation, grid connection approvals, and a declaration signed by the customer confirming the system was installed as described. Missing or incomplete handover docs are a common audit failure — see our Solar Compliance Checklist 2026 for exactly what must be included.

CEC Accreditation Currency

Your CEC accreditation must be current and your endorsement categories must cover the work you are doing. If you are installing battery systems under AS/NZS 5139 but your accreditation does not include battery storage, you have got a problem. The same applies to design endorsements if you are lodging your own STCs.

Compliance with AS/NZS 5033 and AS/NZS 5139

Photovoltaic installations must comply with AS/NZS 5033, and battery storage systems must comply with AS/NZS 5139. Auditors will check that your documentation — including certificates of compliance and electrical safety certificates — reflects compliance with the current versions of these standards.

Common Failure Points

Based on CER compliance outcomes and industry patterns, these are the areas where solar installers most often get caught:

Missing or late STC documentation. STCs must be lodged within 12 months of installation. Late lodgement, or lodgements made after the audit trigger, raises questions about whether the documentation was created after the fact.

Photos not tied to specific jobs or dates. Uploading a generic photo of an isolator or inverter without metadata linking it to a specific installation is not sufficient. Each job needs its own documented photo set.

Incomplete customer handover. Forgetting to get a signed declaration, not providing the Certificate of Electrical Safety, or failing to document the grid connection approval are among the most common compliance failures. Our Solar Compliance Checklist 2026 walks through every required handover document in detail.

AS/NZS 5139 battery storage labelling gaps. Battery storage compliance requirements are more complex than PV-only installations. Labelling requirements under AS/NZS 5139 are specific and mandatory — missing battery system labels, incorrect warning signage, or non-compliant documentation for energy management systems are increasingly common audit findings. More on this in our AS/NZS 5139 Battery Storage Compliance guide.

Expired accreditation or wrong endorsement category. CEC accreditation must be renewed annually. If you lodge STCs during a period when your accreditation had lapsed — even briefly — those claims are invalid.

12-Point Audit Readiness Checklist

Use this before every job, and definitely before any audit request arrives:

  1. STC lodgement completed within 12 months of installation date
  2. Lodgement data matches job documentation (system size, panel count, inverter model, install date)
  3. Job photos captured on-site and date-stamped: roof layout, isolators, inverter labels, switchboard connection
  4. Photos filed against the specific job — not a generic folder
  5. Certificate of Electrical Safety issued and filed
  6. Grid connection approval documented
  7. Customer signed declaration completed and retained
  8. Full handover pack delivered to customer (system specs, warranties, grid connection docs)
  9. CEC accreditation current and correct endorsement category active at time of installation
  10. Battery storage installations: AS/NZS 5139 labelling complete and documented
  11. AS/NZS 5033 compliance documented for all PV installations
  12. All records retained and retrievable for a minimum of 5 years

For the full expanded version of this checklist including document templates, see our Solar Compliance Checklist 2026.

How Digital Job Management Solves the Documentation Problem

The single biggest reason installers fail CER audits is not bad work — it is poor documentation systems. Jobs get finished, photos sit in someone’s phone, paperwork gets delayed, and then six months later when an audit request arrives, the scrambling starts.

Digital job management for solar installers changes this at the process level. When your job management system captures photos, signatures, checklists, and client sign-offs as part of the job workflow — not as an afterthought — audit readiness becomes a byproduct of normal operations.

ServiceM8 for solar installers is the platform we see most commonly adopted by Australian solar businesses for exactly this reason. Job notes, on-site photos (automatically date and location stamped), digital forms, and client sign-offs are all captured in one place and tied to the specific job record. When an auditor requests documentation for a job from 14 months ago, you can pull it in under a minute rather than hunting through inboxes and phone galleries.

The ServiceM8 review covers the platform in depth if you want the full picture, but the compliance documentation use case alone makes it worth evaluating for any solar installer with more than a handful of jobs per month.

If you are not using a digital system yet, ServiceM8 offers a free trial — worth setting up before your next CER lodgement cycle rather than after an audit request.

What Happens If You Fail

The consequences of a failed CER audit range from inconvenient to business-ending, depending on severity:

STC recoupment — If an audit finds that STCs were incorrectly claimed, the CER can require the agent or installer to repay the value of those certificates. For high-volume installers, this can be a significant financial hit.

Accreditation suspension or cancellation — The CEC can suspend or cancel your accreditation based on audit findings. Without an active accreditation, you cannot lodge STCs and cannot legally install solar under the SRES.

Civil penalties — Deliberate or systemic non-compliance can result in civil penalty proceedings. The CER has used these powers, and the dollar amounts are substantial.

Reputational damage — CER enforcement actions are published. For a business that depends on consumer trust and referrals, that is a long-term cost that outlasts the audit itself.

Final Word

CER audits are not a worst-case scenario you prepare for in a panic. They are a normal part of operating in the solar industry in 2026, and the installers who sail through them are the ones who treat documentation as part of the job — not as something to sort out later.

Get your checklist in order. Build your documentation workflow around digital job management. Make sure your accreditation is current and your endorsement categories cover your work. And if you are doing battery storage, get across AS/NZS 5139 now — that is where most gaps are showing up.

For a full rundown of what you need on every solar job, start with the Solar Compliance Checklist 2026. It covers every document, every photo, and every sign-off you need to stay audit-ready year-round.