From 1 July 2026, eligible households in South Australia can access three hours of free electricity every day from 12pm to 3pm under the Australian Energy Regulator’s Solar Sharer Offer (SSO).
You don’t need solar panels to access the offer. You just need a smart meter and to opt in through your electricity retailer. But for battery customers, this scheme is a particularly big deal. It changes the conversation from:
“What feed-in tariff can I get?”
to:
“Can my battery store enough free power during the day to avoid expensive electricity at night?”
That’s where system design really matters.
What You Need to Access the Solar Sharer Offer
Before looking at battery design, it’s worth understanding the basics of the scheme. To access the Solar Sharer Offer, you need:
- A smart meter installed at your property
- To opt in with a participating retailer offering eligible electricity plans
- To be a residential customer in an eligible area (South Australia, NSW, or South East Queensland)
If you don’t yet have a smart meter, you can request one through your retailer or distributor. A compulsory national rollout is underway, with all National Electricity Market customers expected to have a smart meter by November 2030.
Once opted in, your retailer will apply the free power period to your billing automatically during the 12pm to 3pm window each day, up to a daily cap of 24 kWh.
Making the Most of Free Power Without a Battery
Even without a battery, there are ways to reduce your electricity bills using the free power period. If you’re home during the day, you can shift energy usage into the 12pm to 3pm window by running the washing machine, dishwasher, or dryer, charging an electric vehicle, pre-heating or pre-cooling your home with a split-system air conditioner, or scheduling a heat pump hot water system to run during those hours.
If you’re not home, many modern appliances have built-in timers and scheduling functions that can help you shift electricity usage into the free window automatically.
These strategies can reduce your electricity costs on their own. But with a battery, the opportunity is significantly larger.
Why a Battery Turns Three Hours of Free Power Into All-Night Savings
With a home battery system, you’re not limited to using free energy only while the window is open. Your battery can charge during the 12pm to 3pm period and then power your home later in the evening, when grid electricity is at its most expensive.
This is the real value of the Solar Sharer Offer for battery owners: storing free solar energy when it’s abundant and using it during peak pricing periods when it matters most.
How Inverter Size (kW) Limits How Fast Your Battery Can Charge
Many homeowners focus only on battery size when choosing solar systems, but your inverter size matters just as much, especially with a fixed three-hour charging window.
Think of it like a water tank. The kWh rating is the size of the tank, and the kW rating is how wide the pipe filling it is. kWh is storage. kW is speed.
The battery tells you how much energy you can store. The inverter tells you how quickly you can charge or discharge it. For example, a 10 kW battery inverter can charge around 10 kWh per hour, depending on the battery and site conditions. Over a three-hour free power period, that’s up to around 30 kWh of theoretical charging capacity.
However, here’s an important detail – the Solar Sharer Offer caps free usage at 24 kWh per day. That means a 10 kW inverter can comfortably fill the free allowance within the window, but anything above 24 kWh will be charged at standard rates. A well-sized system will aim to charge as close to 24 kWh as possible within the three hours without exceeding the cap unnecessarily.
A smaller 5 kW inverter, on the other hand, may only manage around 15 kWh in that same period. That leaves free energy on the table.
If your battery is large but your inverter is undersized, your system may not be able to fully use the free-power allowance, and you’ll miss out on energy you could have stored for the evening.
How Solar Keeps Your Battery Full After the Free Window Ends
What happens after 3pm is just as important.
In many South Australian homes, solar panels will still be producing solar energy well after the free window ends. That means your system can often cover your household demand through the afternoon, keeping your battery full until later in the day.
When the sun goes down and expensive peak rates begin, your battery is still fully charged and ready to power your home. This is the ideal setup:
- Charge the battery during the free power period (12pm to 3pm)
- Let your solar panels carry the home through the afternoon
- Use the battery at night when grid power is most expensive
Watch Out for Higher Peak Rates on Solar Sharer Plans
One thing to be aware of is that the Solar Sharer Offer is based on a time-of-use tariff structure. That means while you get free power during the middle of the day, the rates outside that window may be higher than a traditional flat tariff.
If you can’t shift much of your electricity usage into the free window or don’t have a battery to store that energy, you could end up paying more overall on an SSO plan compared to your current rate.
This is exactly why battery design matters. A properly sized battery system allows you to maximise the free window and then avoid those higher peak rates by running your home from stored energy in the evening, keeping your electricity costs as low as possible.
When comparing electricity plans, look beyond the headline “free power” and evaluate:
- The free-power allowance (how many kWh you can use for free, and whether there’s a cap)
- The peak usage rate (what you’ll pay outside the free window, especially evenings)
- The daily supply charge
- Whether the plan supports battery charging during the free window
- Whether your system can actually absorb 24 kWh in three hours
Some retailers may offer more generous allowances or unlimited usage during the free period. Others may offset the free window with significantly higher peak rates or daily charges. Do your homework.
How to Design a Battery System for the Free Power Window
Three hours of free power is a great opportunity for South Australian households, but only if your battery system is designed to make the most of it.
Your inverter needs to be large enough to charge the battery within the three-hour window, ideally getting as close to the 24 kWh cap as your household requires. Your battery needs enough capacity to power your home through the expensive parts of the day. And your solar systems need to be set up so solar production, battery storage, and grid charging all work together to minimise your overall energy usage from the grid.
At Solar Wholesalers, this is exactly how we approach battery design. We look at the full picture, such as solar production, battery capacity, inverter sizing, retailer plan structure, and how your system interacts with schemes like the Solar Sharer Offer, so everything works together to reduce your electricity bills year-round.
Want to know if your system is ready for the free-power window? Get a free quote and our team will design a solution tailored to your home.
