Can three zero-cost hours still leave you with a higher bill?
Yes. The Solar Sharer Offer in SA can lower the cost of some daytime electricity without lowering your total bill. To compare it fairly, price your grid usage across every time band, add fixed and other applicable charges, then subtract export credits. Compare the result with your current plan over the same period.
The useful question is not simply whether you can run the dishwasher at lunchtime. It is whether the amount you avoid paying then is larger than any extra cost elsewhere.
For Adelaide households considering a battery, this is the starting point, not the whole decision. A cheaper lunchtime tariff does not move your evening cooking, lighting or cooling into the middle of the day. This guide compares the bill first, then shows what to bring to a SunEnergy battery consultation.
What does the Solar Sharer Offer cover in South Australia?
The Australian Government lists the SA window as 12pm to 3pm, with up to 24 kWh of eligible usage at no usage charge each day. Daily supply charges and usage outside that window still apply. Eligibility includes a residential smart meter, an eligible retailer and being outside an embedded network. Rooftop solar is not required. Confirm your eligibility with your retailer using the government’s current Solar Sharer guidance.
The AER also explains that customers already on competitively priced market offers may not get a lower bill by switching, even if they change their usage. Its Solar Sharer fact sheet distinguishes the regulated offer from other market offers with daytime promotions. Do not assume every plan advertising a daytime window has identical conditions.
Example 1: a zero-cost window, but a higher daily total
Illustration only: all prices below are invented GST-inclusive Australian-dollar amounts, not actual Solar Sharer rates, retailer quotes or Australian household averages. The household imports 12 kWh per day. It has no exports, controlled load, demand charge, discount or other fee. For simple arithmetic, all its paid usage on the hypothetical new plan falls in one 45c/kWh band; real comparisons must use each applicable time band.
| Daily cost item | Current example plan | New example plan |
|---|---|---|
| Grid imports | 12 kWh at 35c | 3 kWh at 0c; 9 kWh at 45c |
| Usage cost | $4.20 | $4.05 |
| Supply charge | $1.00 | $1.30 |
| Total | $5.20 | $5.35 |
Here, the new plan saves 15 cents on usage but adds 30 cents in supply charges. The daily total is 15 cents higher.
Looking only at the 3 kWh priced at zero would miss the result. Multiplying it by the old 35c rate gives $1.05, but that is not the net saving because the remaining charges also changed.
Example 2: the same plan, with more existing use shifted
Keep the same invented rates and the same 12 kWh total. Now suppose 5 kWh falls inside the zero-cost period and only 7 kWh remains in the paid band.
7 kWh × $0.45 + $1.30 = $4.45 per day.
That is 75 cents below the current example plan’s $5.20. No extra electricity has been added; more of the same usage has moved.
Under these particular assumptions, matching the old total requires about 3.33 kWh in the zero-cost window: ($6.70 − $5.20) ÷ $0.45. That is not a universal switching threshold. Different rates, time bands, exports or charges change the answer.
These examples show why two homes can reach different conclusions about the same offer. They are not forecasts, and a single day should not be multiplied into a promised annual saving.
What could a battery change after the free window?
A tariff changes the price of electricity at particular times. A battery can change when stored energy is available to your home. The Australian Government explains that stored energy can be used when solar generation is insufficient or electricity costs more.
If your home still buys substantial electricity after 3pm, that is the part of the bill to bring to a battery consultation. It is particularly worth investigating where daytime solar exports coincide with regular evening imports. Those readings give a starting point for assessing storage, not a promise of savings.
Ask SunEnergy to compare three scenarios using the same household usage: your current setup, a different tariff without new equipment, and a suitable battery with the proposed tariff. Keep installed cost, export credits, remaining grid purchases and the assumptions behind estimated savings visible. The two examples above do not include a battery and cannot establish its payback.
Bring a recent bill, ideally 12 months of interval usage, your solar inverter model and available generation/export records. Our solar app guide helps identify the readings. Your retailer confirms plan conditions; SunEnergy can discuss the equipment options for your home.
Battery buying FAQ: your questions before requesting a quote
1. If electricity is free at lunchtime, why consider a battery?
Because the timing of your household needs may not match that window. Storage is worth assessing when you have energy available to charge it and regular demand later. The question is how much paid grid use a suitable system could replace, relative to its installed cost.
2. Can I charge a battery during the free hours and use it at night?
Potentially, but this must be checked against the retailer’s terms and the proposed system’s settings and capabilities. Ask for the charging source and schedule to be stated in your proposal, including the allowance, charging limits and energy losses. Do not assume all available free electricity can be stored or all evening use covered.
3. What battery size would suit my home?
Start with when and how much electricity you use, not the largest advertised capacity. Usable capacity in kWh describes stored energy; output in kW limits what it can supply at once. Ask SunEnergy to explain the proposed size against your usage and charging opportunity. See the government battery guide.
4. Can a battery be added to my existing solar system?
Have the existing inverter model, system details and installation location assessed before choosing equipment. Ask whether the proposal retains your current inverter or needs additional hardware, and have any extra work itemised. An existing solar system does not by itself confirm compatibility.
5. Will a battery eliminate my electricity bill?
Do not plan on that outcome. Supply charges remain, and the home may still buy grid electricity. Ask to see estimated remaining bills, not just a headline savings figure, with seasonal use and export credits included.
6. What should I send SunEnergy to get a useful battery quote?
Send your recent electricity bill, available usage and solar-monitoring records, and inverter model. Explain whether your priority is evening bills, future household loads or backup. Request an itemised installed price, the proposed operating assumptions, warranty details and any exclusions so you can compare the recommendation meaningfully.
Find out what a battery could do for your Adelaide home
Still buying electricity when your family needs it most? Bring that usage pattern to SunEnergy and request a battery quote based on your home. Explore our Adelaide home battery options, then use the enquiry button below to share your system details and priorities.
SunEnergy provides solar and battery solutions in Adelaide and South Australia, with headquarters at 88 Fullarton Road, Norwood. Ask for a recommendation that shows the proposed equipment, installation scope and the assumptions behind the savings estimate.
Free hours are one part of the decision. The next step is finding out whether a battery can make more of the energy available to your home.
Sources
Australian Government: Solar Sharer Offer
Australian Energy Regulator: Solar Sharer Offer fact sheet
Energy Made Easy: Solar Sharer Offer explained
Australian Government: Solar PV and batteries
Australian Government: Battery capacity and power
Reviewed 18 September 2026. Numerical examples are original illustrative calculations, not current tariffs or customer results.
