NSW Commercial Battery Rebate 2026: BESS3, BESS4 and BESS5

The new NSW battery activities apply to eligible installations completed on or after 1 September 2026. You will often hear the incentive called a rebate, but it is technically a certificate-based discount. It can reduce the upfront cost of a battery, sometimes substantially, but the amount depends on how the system is designed and how the certificates are valued.

The short version

• It is a NSW scheme. The site must be in NSW and connected to the NSW electricity network. Off-grid sites are not eligible.
• The value is based on Peak Reduction Certificates, or PRCs. Their market price can change, so any dollar estimate should show the assumptions used.
• The scheme is legislated to run until 2050 and has no current closing date. There is time to assess the project properly, although the rules and individual activities can be updated along the way.
• New solar is optional, but it can increase the battery discount. The installations must meet the 90-day rule and the new solar capacity must be at least 25% of the battery's usable capacity.
• The inverter matters. If the battery's usable capacity is more than six times the inverter output, the battery is not eligible. Between four and six times, it may qualify but earn fewer PRCs than it would with a larger inverter.
• Other incentive thresholds still apply. A system can qualify for the NSW discount but fall outside a federal battery or solar incentive, so combined incentives need to be checked separately.

Two examples worth keeping in perspective

The NSW Government has published an indicative example of about $355,000 for a medium dairy farm. At the larger end of the industry worked examples, a 4,437 kWh nominal battery system with 1 MW of new solar produced an indicative $1,296,326 in combined incentives.

The $1.296 million figure is not a scheme maximum or a standard rebate. It used a 3,993.3 kWh usable battery, a 1.5 MW inverter, 373,772 PRCs and potential solar STCs under the proposed SRES expansion. Both figures depend on eligibility, system design, certificate prices, location, installation timing and the rules in force when the work is completed.

What this actually is

The incentive sits under the Peak Demand Reduction Scheme, or PDRS. The scheme rewards equipment that can reduce demand on the grid during peak periods. Batteries qualify because they can store energy and shift when electricity is drawn from the grid.

For most projects, the incentive appears as an upfront discount in the quote. An Accredited Certificate Provider, or ACP, creates the PRCs and sells them, then passes the agreed value through the commercial arrangement with the installer. Larger projects may use a different payment structure.

The nomination paperwork must be completed before installation begins. The product list should also be checked with the ACP before equipment is ordered or installed. A battery that has already been installed cannot be claimed retrospectively.

It is not the federal scheme

The federal Small-scale Renewable Energy Scheme creates Small-scale Technology Certificates, or STCs. The NSW scheme creates PRCs. They are separate certificates with separate rules and prices.

STCs can be sold on the open market or through the federal clearing house, where the price is currently set at $40 per certificate. PRCs are traded in their own market, so the PRC price used in a quote needs to be stated clearly.

If both incentives appear on a quote, ask what certificate price has been used for each, when the calculation was run and what happens if the value changes before the certificates are created and sold.

Which activity applies to you

There are three new activities, based on the type of site and the battery's usable capacity.

BESS3 covers apartment buildings with at least four dwellings and a battery greater than 20 kWh and up to 200 kWh. The capacity used in the certificate calculation is also capped at 5 kWh per dwelling.

BESS4 covers non-residential business sites, excluding data centres, with a battery greater than 20 kWh and up to 200 kWh.

BESS5 covers larger commercial and industrial sites, excluding data centres, with a battery greater than 200 kWh and up to 30,000 kWh. Only the first 10,000 kWh can earn PRCs.

A dairy, cold room, workshop or pub using a battery of up to 200 kWh will generally fall under BESS4. A larger battery at the same type of site will generally fall under BESS5.

You do not need existing solar

Solar is not required for BESS3, BESS4 or BESS5. A battery-only project can still receive the discount. New or additional solar simply allows the project to use the higher PRC calculation if it meets the sizing and 90-day rules.

Existing batteries are treated differently. Under BESS3, there cannot already be a battery at the same National Metering Identifier. Under BESS4 and BESS5, the site cannot have previously received an installation under either of those activities.

Choose an inverter that is too small and you get nothing

The battery inverter must be large enough for the battery it serves.

The rule states that usable battery capacity must not exceed six times the battery inverter output. The clearest way to check this is to divide usable battery capacity in kWh by inverter output in kW. The result is the battery duration in hours.

• More than six hours: the battery is not eligible.
• Between four and six hours: the battery may qualify, but the inverter limits the capacity used to calculate PRCs.
• Four hours or less: the inverter no longer reduces the counted battery capacity, although other scheme caps can still apply.

For a 100 kWh usable battery, a 10 kW inverter does not qualify. A 17 kW inverter gets below the six-hour limit, but the PRC calculation counts only 68 kWh because it is capped at four times the inverter output. A 25 kW inverter brings the system to four hours, so the full 100 kWh can be used in that part of the calculation.

Inverters cost money, so two quotes using the same battery capacity may specify different inverter outputs and produce different PRC estimates. A smaller inverter may still suit the site's load and network connection, but its effect on eligibility, certificate value and system performance should be clear.

If the ratio is between four and six hours, ask whether there is a sound design reason for it and what moving closer to four hours would change. The right answer depends on the site's load, connection limits, equipment cost and intended use of the battery, not the rebate alone.

The 90-day rule

New or additional solar increases the PRC calculation for the battery. The solar itself does not earn PRCs under this scheme.

Two conditions apply:

• The new solar capacity must be at least one quarter of the battery's usable capacity. A 100 kWh battery therefore needs at least 25 kW of new solar.
• The battery must meet the scheme's 90-day timing requirement in relation to the new solar installation.

The NSW Government website says the new solar can be installed within 90 days before or after the battery. However, other industry bodies are advising that the solar should be completed first, with the battery installed within the following 90 days. Until this is clarified, the safest approach is to complete the solar first and confirm the proposed timing with the ACP in writing.

Projects can move beyond 90 days once planning, network approval, procurement and installation schedules are allowed for. If the solar and battery will be staged, record the intended completion dates and who is responsible for keeping them within the accepted window.

What you can claim on top

The NSW discount can sometimes be combined with federal STCs, but the project must meet the rules of each scheme independently.

Under the federal Cheaper Home Batteries Program, an eligible battery must currently have a nominal capacity between 5 kWh and 100 kWh and be installed with a new or existing solar PV system of no more than 100 kW. STCs are calculated on no more than the first 50 kWh of usable battery capacity, with lower factors applying above 14 kWh and again above 28 kWh.

Federal solar STCs currently apply to eligible solar PV systems up to 100 kW. The Australian Government has announced an expansion for systems above 100 kW and up to 1 MW, intended to apply from 1 October 2026, but this remains subject to the required regulations being in place.

Crossing one of these thresholds does not necessarily make the larger system a poor choice. It changes which incentive applies and may change the economics. Systems above the small-scale solar limit may be eligible under the Large-scale Renewable Energy Target instead. The sensible comparison is the total project value on either side of the threshold, including energy savings, demand-charge savings and certificate income.

Worked examples

These examples show how the battery size, inverter, new solar and federal eligibility can change the result. They are based on figures presented in an industry webinar and are not quotations.

BESS3: apartment buildings

The first battery is over the federal program's 100 kWh nominal-capacity limit, so it receives PRCs only. The third example shows the higher PRC calculation when enough new solar is added within the required timeframe.

BESS4: smaller commercial systems

The 157 kWh battery is too large for the federal battery program, but it can still receive the NSW PRCs and eligible solar STCs. Where battery STCs are shown without new solar, the example assumes there is an eligible existing solar system at the site.

BESS5: larger commercial systems

The solar STCs in the 250 kW and 1 MW scenarios depend on the proposed SRES expansion coming into effect and the project meeting its final rules. The 1.175 MW solar system sits above the proposed small-scale limit, although another federal certificate pathway may be available.

All dollar figures are rounded and indicative only. The webinar calculations used $2.75 per PRC, $38.85 per STC, the Ausgrid network and STC Zone 3. Certificate prices, rules and site assumptions can change. Do not use these figures for quotation purposes.

What counts as an eligible battery

For BESS3 and BESS4, the battery must be on the Clean Energy Council approved list. The battery and any newly installed inverter must have warranty cover of at least 10 years, and the battery warranty must guarantee at least 70% of usable capacity after 10 years.

BESS3 batteries must be installed outdoors. BESS4 installations must comply with AS/NZS 5139 and use an approved installer. Both require the relevant planning and network approvals. BESS3 also requires a minimum net customer payment of $1,000 excluding GST per item of eligible equipment; for BESS4 it is $5,000 excluding GST.

BESS5 has different product requirements. The battery must be tested in accordance with UL 9540A, installed by a suitably licensed person and have all required planning and network approvals.

For all three activities, the battery must be internet connectable and controllable by a Demand Response Aggregator. In practical terms, it must be capable of participating in a virtual power plant.

Capability is not the same as enrolment. BESS3, BESS4 and BESS5 do not require you to enter a VPP contract to receive the installation discount. Joining a VPP later is a separate decision, with its own provider, contract and terms.

The product and warranty requirements are useful filters. They narrow the eligible equipment to batteries and newly installed inverters with the required approvals, warranty period and retained-capacity cover.

How to read the rebate estimate

The NSW Government has published examples to show the potential scale of the incentive, including about $355,000 for a medium dairy farm. They are examples, not fixed offers.

We will include an estimated incentive in a quote, together with the assumptions used to calculate it. The final value can change if the battery or inverter specification changes, new solar is added or removed, the installation timing changes, or the PRC price moves before the certificates are sold.

If someone gives you one confident PRC figure with no assumptions written down, that should give you pause. A useful quote should show the usable battery capacity, inverter output, expected PRC count, PRC price, distribution network, calculation date, relevant fees or margin, GST treatment and who carries the risk if the certificate price changes. If federal solar STCs are included, the postcode zone and STC price should also be shown.

What to check in a quote

• The battery and inverter have been sized around the site's interval data, tariff and operating pattern, including any seasonal peaks.
• The quote distinguishes nominal battery capacity from usable capacity and shows the inverter output.
• Any higher calculation for new solar states the new solar capacity and the planned installation dates for both systems.
• The equipment, installer, ACP, planning approvals and network approvals meet the relevant activity requirements.
• The nomination form will be signed before installation begins.
• The PRC estimate shows its certificate price, calculation date and other assumptions.
• Any federal battery or solar discount has been checked separately against the rules in force at the time of installation.

The PDRS is legislated to run until 2050, so there is an opportunity to assess the project properly. The main timing constraint arises when new solar and a battery are being staged: the installations must meet the 90-day rule to use the higher PRC calculation.

This guide is general information only and is not financial, tax, legal or engineering advice. Eligibility depends on the scheme rules and evidence requirements in force on the installation date. Scheme eligibility does not replace planning, network, electrical safety, fire safety or workplace requirements. Certificate quantities and values are not guaranteed until eligibility is confirmed and the certificates are created and sold. Rules, targets, deeming factors and certificate prices can change. GST, depreciation and other tax treatment can vary between businesses. Check the current NSW and federal requirements and obtain advice appropriate to the project before committing.