Battery Retrofit Campbelltown: Add Storage to Existing Solar | Kratos Energy

Battery Retrofit Guide for Campbelltown: Adding Storage to Existing Solar

Already have rooftop solar on your Campbelltown NSW 2560 home and considering battery storage?

In many cases, you can add a battery without replacing your entire solar system.

The right retrofit depends on your existing inverter, solar-system size, daytime exports, evening electricity consumption, electrical supply and whether you want blackout backup.

For an existing solar owner, the process should start with an assessment—not with choosing the biggest battery available.

The five questions to answer first are:

1. Is the existing solar system still performing properly?

2. Can the current inverter work with the proposed battery?

3. How much excess solar is available for charging?

4. How much electricity do you use after sunset?

5. Do you want essential-load or whole-home blackout backup?

Kratos Energy offers solar-connected battery systems designed around existing generation and household consumption. Explore Kratos battery storage solutions

Can You Add a Battery to Existing Solar in Campbelltown?

Yes, in many cases.

Australia's Cheaper Home Batteries Program specifically supports eligible battery systems connected to new or existing rooftop solar, so battery retrofits are now a major part of the Australian market. The Clean Energy Regulator reported that a substantial proportion of 2026 battery installations were retrofits to existing solar systems. (Energy Australia)

There are two main technical pathways.

The best solution depends on the equipment already installed.

Step 1: Check Your Existing Solar System

Before installing a battery, the installer should assess the solar system you already own.

Check:

• Solar-array capacity

• Panel age and condition

• Inverter make and model

• Inverter age

• Current solar generation

• Average solar exports

• Single-phase or three-phase supply

• Switchboard condition

• Existing network approval

If your panels are producing reliably and your inverter is relatively new, there may be no reason to replace them.

The aim should be:

Keep equipment that still adds value and upgrade only what the battery installation requires.

Step 2: Decide Between AC and DC Coupling

AC-Coupled Battery

AC coupling is a common way to retrofit a battery to an existing solar system.

Your existing solar inverter continues converting panel electricity into AC electricity, while the battery uses a separate battery inverter or integrated power-conversion system.

A simplified flow is:

Solar panels → existing solar inverter → home → battery

The Australian Government notes that AC coupling is the usual arrangement when adding a battery to an existing solar system. (Energy Australia)

AC coupling can suit you if:

• Your existing inverter still works well

• The inverter has useful warranty life remaining

• You do not want to replace functioning equipment

• Your preferred battery has its own inverter

• You want a relatively straightforward retrofit

Hybrid-Inverter Retrofit

A hybrid inverter manages both compatible solar panels and battery storage.

Replacing your existing inverter with a hybrid model may make sense when:

• The existing inverter is old

• It is already experiencing faults

• You plan to expand the solar array

• You want an integrated solar-and-battery platform

• Your preferred battery requires a compatible hybrid inverter

Replacing a healthy inverter purely because you are adding a battery may not always provide the best value.

Step 3: Measure How Much Solar You Actually Export

A battery needs electricity to charge.

Before selecting capacity, check how much solar your home currently exports during daylight hours.

Example A

Average excess solar:

12kWh/day

Night-time grid use:

9kWh/day

This household may have enough recurring solar surplus to make good use of a battery around its evening-demand range.

Example B

Average excess solar:

4kWh/day

Night-time grid use:

12kWh/day

A large battery may regularly remain partly empty unless the household:

• Adds more solar

• Uses off-peak grid charging

• Changes energy-use patterns

• Selects a smaller battery

This is why battery size should not be chosen from your solar-system kW rating alone.

Step 4: Size the Battery Around Evening Consumption

One of the best battery-sizing starting points is:

How much electricity do you use between solar production falling and the following morning?

As a general assessment guide:

*Indicative ranges only. Final capacity should consider solar surplus, reserve settings, losses, power output and future demand.

A 20kWh battery is not automatically better than a 10kWh battery.

If your home can only recharge and use 8–10kWh regularly, additional capacity may deliver limited everyday benefit.

Step 5: Check Battery and Inverter Compatibility

Battery compatibility is not universal.

Even if an inverter is advertised as hybrid, it does not necessarily work with every battery.

The installer should confirm:

• Exact inverter model

• Battery model

• Supported battery voltage

• Communication protocol

• Firmware

• Maximum charge rate

• Maximum discharge rate

• Usable battery capacity

• Backup compatibility

This is particularly important when retrofitting an older solar system.

Do not purchase a battery based only on capacity or brand reputation before compatibility is confirmed.

Step 6: Decide Whether You Need Blackout Backup

A home battery does not automatically mean your home will stay powered during an outage.

Backup operation requires the correct:

• Battery

• Inverter

• Switching equipment

• Electrical configuration

• Backup circuits

The Australian Government specifically notes that batteries can provide electricity during outages if configured to do so. (Energy Australia)

There are two common approaches.

Essential-Load Backup

Only nominated circuits stay powered.

Typical choices include:

• Refrigerator

• Lighting

• Wi-Fi

• Selected power outlets

• Security equipment

This generally reduces the battery power required during an outage.

Whole-Home Backup

A larger portion of the home remains available.

However, appliances such as:

• Ducted air conditioning

• Electric ovens

• Induction cooktops

• Pool pumps

• EV chargers

can create very high instantaneous demand.

For backup design, battery power in kW matters as much as battery capacity in kWh.

Step 7: Check the Switchboard and Phase Configuration

Adding a battery can involve more than mounting equipment on a wall.

The installer should inspect:

• Main switchboard

• Available breaker space

• Metering

• Earthing

• Existing solar protection

• Single-phase or three-phase supply

• Backup-circuit configuration

Older properties may require switchboard work before the battery can be installed safely and compliantly.

This should be identified in the quote—not added unexpectedly during installation.

Campbelltown Network Connection: What Changes?

Campbelltown is within the broader Endeavour Energy network area, so solar-and-battery systems must comply with the applicable network connection process.

Endeavour Energy states that a licensed installer normally manages the application, system design, installation and safety checks. It also advises customers to notify the network when upgrading solar or battery equipment and to ensure systems remain within applicable export limits. (Endeavour Energy)

A battery retrofit may require network consideration if you are also:

• Replacing the solar inverter

• Increasing inverter capacity

• Adding more solar panels

• Changing export settings

• Modifying the existing generation connection

Your installer should confirm the requirements for the specific Campbelltown property before finalising the design.

Should You Add More Solar at the Same Time?

Sometimes.

Consider expanding the solar array if your existing system produces very little surplus electricity.

For example:

Existing solar: 5kW
Daytime household use: high
Regular solar export: only 2–4kWh/day
Proposed battery: 13.5kWh

In this situation, the battery may have limited solar energy available for charging.

A wider upgrade could include:

additional panels + suitable inverter + battery

But additional solar also affects:

• Roof space

• Inverter capacity

• Network approval

• Export settings

• Total project cost

Solar expansion and battery sizing should therefore be assessed together.

2026 Battery Rebate for Existing Solar Owners

Eligible Campbelltown homeowners with existing solar may qualify for the Australian Government's Cheaper Home Batteries Program.

The program supports eligible small-scale batteries connected to new or existing rooftop solar. (Energy Australia)

From 1 May 2026, battery support is tapered by usable capacity:

• First 14kWh — full applicable STC factor

• Above 14kWh to 28kWh — 60% factor

• Above 28kWh to 50kWh — 15% factor

The Clean Energy Regulator says the revised structure is designed to maintain support broadly equivalent to around a 30% reduction in installation cost across battery sizes, although the actual dollar benefit depends on certificate values and eligibility. (Clean Energy Regulator)

Kratos' calculator can estimate the current support based on usable battery capacity and postcode. Use the Kratos Battery Rebate Calculator

Do not select an oversized battery simply because additional capacity attracts a larger total rebate.

Battery Retrofit Example

Consider a Campbelltown homeowner with:

Existing solar: 6.6kW
Existing inverter: 5kW, four years old
Average daytime export: 11kWh
Evening grid consumption: 9kWh
Goal: Reduce night-time imports + essential-load backup

A sensible assessment may compare:

Option 1 — AC-Coupled Battery

Keep the working inverter and add compatible battery equipment.

Option 2 — Hybrid Upgrade

Replace the existing inverter and install an integrated solar-and-battery platform.

Because the current inverter is only four years old, the AC-coupled option may avoid replacing useful equipment.

But if the homeowner intends to expand solar or needs specific backup functionality, the hybrid option may still provide better long-term value.

The correct answer depends on the complete system—not battery capacity alone.

What Should a Battery Retrofit Quote Include?

Before accepting a Campbelltown battery quote, check that it clearly shows:

A retrofit quote should explain how the new battery integrates with what you already own.

Frequently Asked Questions

Adding a Battery to Existing Solar in Campbelltown: The Bottom Line

For an existing solar owner in Campbelltown NSW 2560, a good battery retrofit follows a simple sequence:

Assess existing solar → measure exports → measure night-time consumption → check compatibility → decide backup requirements → size the battery → confirm network and rebate requirements.

You may be able to keep your current panels and inverter.

Or your system may benefit from a wider solar, inverter and battery upgrade.

The important point is to make that decision from real generation and consumption data—not from a standard battery package.

Explore Kratos battery storage solutions

Estimate your 2026 battery rebate

Request a tailored Kratos solar and battery quote

A good battery retrofit should make better use of the solar you already own—not force you to start again.