VEU vs ESS vs STC (2026): The Multi-State Contractor’s Compliance Guide

1. Which certificate applies to my job?

Before the detail, the question most contractors actually have: for a given activity, in a given state, which scheme am I even working with? Here’s the fast reference for five common jobs.

Rooftop solar deserves its own note rather than a table row, because the boundary is where a lot of otherwise-careful quotes go wrong. Residential systems up to 100kW create STCs under the federal small-scale scheme. Above that nameplate capacity, a system generally moves into the Large-scale Renewable Energy Target and creates Large-scale Generation Certificates (LGCs), not STCs — a different mechanism with different economics. Victoria’s newer Commercial & Industrial Solar PV VEU activity can add a state-based VEEC on top of whichever federal certificate actually applies at that scale, so it’s worth confirming STC vs LGC eligibility before assuming small-scale numbers carry through to a C&I-sized system.

2. The three schemes at a glance

All three schemes do the same broad job: subsidise energy-efficient or emissions-reducing upgrades by letting an installer create a tradeable certificate instead of asking the customer to wait for a government cheque. Where they diverge is jurisdiction, legislation, the regulator, and the exact mechanics of eligibility, evidence, and audit — and that divergence is the entire problem for a contractor working across state lines.

3. Victoria’s VEU and the VEEC

The Victorian Energy Upgrades (VEU) program has run since 2009 and was extended to 2045 under the Victorian Energy Efficiency Target Amendment (Energy Upgrades for the Future) Bill 2025. It works activity by activity: heat pump hot water, reverse-cycle air conditioning, ceiling insulation, commercial and industrial solar PV, high-efficiency motors, and dozens more, each with its own numbered Activity Definition that sets out exactly how a VEEC is calculated.

Eligibility hurdles

• Product register check at install time, not quote time. The specific brand and model must appear on the relevant VEU product list on the day of installation — listings change.
• Existing-system replacement rules. High-value activities like heat pump hot water and space heating/cooling generally only qualify when a functioning existing unit is decommissioned; new-build installs with no prior system often generate less, or nothing.
• Warranty conditions. Since 31 March 2025, products under the water heating and space heating/cooling activities must carry a five-year manufacturer’s warranty from install date.
• Evidence at the activity level. Photographic evidence of the existing unit, the new installation, and serial numbers is mandatory and activity-specific — lighting activities, for instance, carry their own geo-tagged photo rules for decommissioned equipment.

Co-payment rules

Since early 2025, VEU has required a minimum customer contribution on heating and cooling activities, introduced to close down “free appliance” marketing the ESC linked to poor-quality installs.

Accreditation, audits & records

Creating VEECs requires Accredited Person (AP) status: an annual “fit and proper person” and “competent and capable” assessment, with accreditation expiring and renewing every 12 months. APs must also undergo an independent assurance audit at least once every two years, at their own cost, via an ESC-approved auditor, plus any additional compliance audits if issues surface. Records must be kept for six years after VEEC creation.

4. NSW’s Energy Security Safeguard: ESS and PDRS

This is where the naming trips people up, so it’s worth untangling before building a workflow around it. The NSW Energy Security Safeguard is the umbrella; underneath it sit two separate certificate schemes:

• Energy Savings Scheme (ESS) — incentivises efficiency upgrades (lighting, hot water, HVAC, draught-proofing, insulation) and issues ESCs.
• Peak Demand Reduction Scheme (PDRS) — incentivises peak-demand-cutting upgrades (air conditioners, pool pumps, batteries, VPP participation) and issues PRCs.

Most contractors are accredited under both at once as an Accredited Certificate Provider (ACP), since one job — a high-efficiency air conditioner, say — can be eligible under both simultaneously via different calculation methods. New ESS and PDRS Rules commenced 1 July 2026; both run day-to-day through IPART’s TESSA platform.

Eligibility hurdles

• Accepted product lists in TESSA, checked at implementation, organised by calculation method (HEER for home retrofits, HVAC1/SYS2 for air conditioning, WH1 for water heating, BESS2 for batteries).
• Method suspensions happen mid-year. BESS1, an earlier battery method, was suspended from 1 July 2025 — eligibility can be pulled outside the annual Rule cycle.
• Minimum Requirements of Conduct. IPART’s rules on how ACPs and representatives engage customers, from first contact to sign-off, are assessed at accreditation and during implementation.
• Monthly implementation reporting. Some methods require ACPs to upload implementation data to TESSA monthly, in a prescribed CSV format, separate from certificate registration itself.

Co-payment rules

NSW doesn’t run one flat co-payment figure — minimum payments are set per activity. Household lighting, for example, sits around $30 plus GST at the low end, with more complex installs requiring more. The constant across NSW activities: a genuinely “free” upgrade isn’t compliant. Consumers must pay at least the applicable minimum, sign a nomination form before installation, and confirm satisfaction after.

Accreditation, audits & records

Becoming an ACP involves an accreditation fee, certificate registration fees, and the cost of compliant business processes — IPART explicitly advises smaller operators to weigh accreditation against partnering with an existing ACP. Audits run against a Detailed Scope of Works and approved sampling plan through an Audit Services Panel, covering calculations, record-keeping, and customer conduct. Records must be kept for at least six years after ESC/PRC creation — an obligation that continues even after accreditation lapses.

5. The Federal STC scheme (SRES)

STCs sit under the Small-scale Renewable Energy Scheme (SRES), part of the Renewable Energy Target administered by the Clean Energy Regulator (CER). Unlike VEU and ESS/PDRS, STCs apply Australia-wide — no separate federal accreditation per state, but federal product and installer requirements apply on every job, everywhere.

Eligibility hurdles

• CEC approved product lists gate every claim — a product removed mid-project can invalidate a claim even if it was compliant at quote stage.
• Installer/designer accreditation now sits with Solar Accreditation Australia (SAA) — a contractor who hasn’t transferred can’t claim STCs until the new SAA number issues.
• Battery STC factor tapers by size. From 1 May 2026: 100% for the first 14kWh of usable capacity, 60% for the next tranche to 28kWh, 15% up to 50kWh — bigger batteries earn proportionally fewer certificates per kWh.
• Recalled products are automatically ineligible under an active Australian Consumer Law recall.

Co-payment rules

No mandated minimum. The certificate value is typically assigned to an agent (installer or retailer) for an upfront discount — the “co-payment” is whatever remains of retail price after the STC discount, market-set rather than regulator-fixed. The 2026 small-scale technology percentage sits at 11.67%.

Accreditation, audits & records

The CER can request documentation behind an STC claim for up to five years from creation — prior approval doesn’t exempt you from producing evidence on request. Retailers must separately keep consumer-disclosure records (payback period, savings estimates, conflicts of interest) for at least five years. Installers must retain three-stage, geotagged, timestamped installation photos and a signed compliance statement confirming accreditation, attendance, and approved-product use.

6. Product eligibility hurdles compared

The single biggest source of failed claims across all three schemes is the same mistake in three outfits: relying on a product’s eligibility at quote time instead of re-checking the register on install day.

7. Co-payment and minimum contribution rules

Co-payment rules are one of the most visible differences between the schemes and a frequent source of non-compliance when teams treat “customer contribution” as a single number.

Best practice for multi-state teams: treat the highest applicable minimum as the floor on any job that could touch more than one scheme, and always collect a signed nomination / customer contribution form on the day of installation.

8. Same job, two rulebooks: a border-town case study

9. The multi-state contractor’s problem

Once a business operates on both sides of a state border (or expands further), the compliance surface multiplies:

• Three separate accreditations (AP + ACP + SAA/CER)
• Three product registers that change independently
• Three co-payment regimes
• Three audit cycles and retention clocks
• Three different digital platforms (VEU Registry, TESSA, REC Registry)

Most failed claims and audit findings in multi-state businesses come from teams treating the schemes as interchangeable or assuming “what worked in Victoria will work in NSW.” They don’t.

10. Building one audit-proof workflow

The highest-leverage change is to stop assembling evidence after the fact and start capturing the strictest common requirements at the point of installation.

Retain the complete folder for a minimum of six years from certificate creation. That single retention policy satisfies the strictest of the three schemes and eliminates the need to track separate clocks.

11. FAQs

12. Bibliography & further reading