Solar export limiting in Perth: constrained suburbs and what to do about it

When you install solar in Perth, your system connects to Western Power's network and can export surplus electricity to the grid. But in some suburbs, the local network infrastructure can't safely handle the volume of solar export that would occur if every home ran a 5–6.6kW system at full export. In these areas, Western Power limits the amount of electricity your system can export.

This is called export limiting or network constraint. It doesn't affect your self-consumption — your panels can still produce as much electricity as they generate, and you can use all of it within your home. Only the amount sent to the grid is capped.

How export limiting works

A network-constrained area might have an export limit of:

• 1.5 kW — the most common constraint for older suburban areas
• 0 kW (no export / zero-export) — rare, for the most constrained areas
• Variable limits — some areas have limits that change by time of day or season

When your inverter detects that you're about to exceed the export limit, it throttles back its output. Your solar panels may be generating 5kW, but if your house is consuming 2kW and the export limit is 1.5kW, the inverter caps total generation at 3.5kW (2kW consumed + 1.5kW exported), leaving 1.5kW of generation potential unused.

The May 2026 rule change (AS4777.2 update) introduced a remote monitoring requirement for systems over 10kW. For residential systems under 5kW inverter capacity: the 2026 rules require that any inverter that can't meet the remote management specification has its export capped to 1.5kW — this is separate from suburb-level network constraints. A compliant inverter in an unconstrained suburb can export up to the 5kW inverter limit.

Affected suburbs in Perth

Network constraints are most common in:

• Northern growth corridors: Butler, Alkimos, Eglinton, Yanchep, Two Rocks, and surrounding estates. Rapid residential development in these areas has outpaced substation upgrades in some pockets.
• Eastern outer suburbs: Some parts of Ellenbrook, The Vines, Upper Swan, and Brigadoon.
• Older inner suburbs with dense solar uptake: Some established areas with high existing solar penetration have reached distribution transformer capacity, though this is less predictable.

This list is not exhaustive and changes as Western Power upgrades infrastructure. Network constraints are managed at individual transformer and feeder level — two streets in the same suburb may have different limits.

How to find out if your property is constrained

The definitive check: Your solar installer is required to check with Western Power for your specific address during the design and connection application process. When your installer submits the connection application, Western Power's network portal returns the export limit (if any) for your address.

Before choosing an installer: Ask any solar installer you're getting a quote from to check your address's export limit as part of their site assessment. This is standard practice for reputable installers. An installer who doesn't mention network constraints should be asked directly.

Direct check: You can contact Western Power's Distributed Energy connections team (1800 622 008 or via the Western Power website) and provide your address. They can advise on applicable limits.

What you can do if your property is constrained

Option 1: Accept the limit and right-size the system

A 1.5kW export limit doesn't prevent you from having a larger solar system — it just means that on a sunny afternoon when you're not home, generation above 1.5kW above your consumption gets curtailed. If your household has reasonable daytime load (always-on pool pump, heat pump hot water during the day, someone working from home), the effective impact of the 1.5kW export cap may be small.

A system analysis based on your consumption profile will show how much annual generation is lost to curtailment at a given export limit. For a household consuming 6kWh/day before 3pm, a 6.6kW system with a 1.5kW export limit may only be curtailed for 1–2 hours on clear summer days — an acceptable trade-off.

Option 2: Add a battery to absorb curtailed generation

A battery converts curtailed export into stored energy. Instead of letting the inverter throttle back, a battery absorbs the excess solar generation that would otherwise exceed the export limit. The battery charges during the solar peak and discharges in the evening.

For households in constrained areas, the battery's economic case is strengthened because the alternative to battery storage is wasted generation (curtailed solar) rather than export at 2c. Battery payback in a heavily constrained area can be meaningfully better than in an unconstrained area.

Option 3: Install a self-consumption system (zero-export)

In zero-export areas, some households install solar with an export-limiting device that monitors grid export in real-time and throttles the inverter to maintain zero export. This keeps all generation within the property boundary. The economic case is entirely based on self-consumption savings — no DEBS export credits.

Option 4: Wait for network upgrade

Western Power is progressively upgrading constrained network areas as part of its grid modernisation program. If your suburb has recently been flagged for upgrade, there may be a case for delaying solar installation until the constraint is lifted. Ask Western Power about planned upgrades for your feeder/substation.

Does export limiting affect the WA Battery Scheme?

No. The WA Battery Scheme rebate ($130/kWh, max $1,300 for 10kWh) applies to battery storage regardless of whether your property has an export limit. In fact, as noted above, the battery's value is higher in constrained areas, making the scheme particularly attractive there.

System design in constrained areas

If your property has a 1.5kW export limit:

• Panel oversizing is less valuable: The excess generation above your self-consumption + 1.5kW export is curtailed. Very large systems (10kW+) see proportionally more curtailment.
• East-west panel splits can help: Spreading generation across morning and afternoon rather than peaking hard at noon reduces peak instantaneous output and curtailment.
• Battery inclusion in the initial design: If a battery is on your radar at all, a constrained area is the strongest case for including it from the start rather than retrofitting.

Network constraint information changes as Western Power upgrades infrastructure. Always verify your specific address's export limit with your installer or Western Power before purchasing a system. The suburb examples above reflect known constraints as of mid-2026 and may have changed.