In short
- Solar suits a cold store well: refrigeration runs all day, so the site uses almost all the power the panels make.
- It only cuts the daytime part of the bill. The overnight load stays, whatever size you install.
- A battery rarely pays on overnight storage alone. Test it against your demand charge instead.
Yes, solar usually saves a cold store real money in Australia, but only on the power it uses in daylight. Because refrigeration never stops, a cold store soaks up nearly everything a well-sized system makes. That gives one of the best returns per kW of any business. What solar can't do is touch the night-time load, and that decides how big the system should be.
| Quick facts | Solar for a cold store |
|---|---|
| Share of solar used on site | often 85–90% on a well-sized system |
| Part of the bill solar can cut | daytime energy, and sometimes the demand charge |
| Part it can't cut | night-time use and the fixed daily charge |
| What to send | one recent bill; we get the interval data from it |
| Battery | usually tested against the demand charge, not overnight use |
Why does solar suit a cold store?
Three things work in a cold store's favour.
- The load is steady. Compressors run day and night, so there's almost always a load ready to use what the panels make. Little goes to the grid for a small credit.
- The load rises with the heat. Refrigeration works hardest on hot, sunny afternoons, which is when solar makes the most power.
- Cold stores have big roofs. A large, flat or low-pitched roof usually has room for the system the load needs.
The catch is the night. A cold store might use half or more of its power after dark, and panels make nothing then.
How much will solar save a cold store?
Here is a worked example with made-up figures. These are example figures, not our prices or a real site.
A Brisbane cold store uses about 1,500 kWh a day, spread fairly evenly across 24 hours. It puts in a 100kW system, which makes about 145,000 kWh a year, or about 400 kWh on an average day.
- The site uses about 90% of the solar itself, about 360 kWh a day. That covers roughly a quarter of its power.
- At $0.28 for each kWh it no longer buys and $0.05 for what goes to the grid: 130,500 kWh × $0.28 = $36,540, plus 14,500 kWh × $0.05 = $725. Yearly saving $37,265.
- At an example price of $73,000 after the STC discount, that pays back in about 2.0 years.
The same assumptions give other site types for comparison on commercial solar cost. The cold store comes out ahead because it uses the most of its own solar.
Should a cold store install a bigger system?
Usually not much bigger than its daytime load. Each extra kW makes power at the same time of day as the first, when the site is already covered.
On the same example, doubling to 200kW makes about 290,000 kWh a year. Midday output now runs well past what the refrigeration uses, so only about 55% is used on site:
- 159,500 kWh × $0.28 = $44,660, plus 130,500 kWh × $0.05 = $6,525. Yearly saving $51,185.
- The second 100kW adds about $13,900 a year, well under half what the first 100kW earns.
Whether that's worth it depends on the price of the extra panels in your quote. Divide the extra price by $13,900 to see its payback. The interval data we get from your bill shows where that point falls for your site.
Is a battery worth it for a cold store's overnight load?
Usually not for overnight storage alone. In the 100kW example, only the 10% the site doesn't use is spare, about 14,500 kWh a year. Stored and used at night instead of exported, each kWh is worth $0.28 instead of $0.05, so the gain is about $3,300 a year, before charging losses and cloudy days. Compare that with the battery price in your quote, over the years its warranty covers.
The demand charge is the better test. Cold stores often set their peak when several compressors start together, after a defrost cycle, or when trucks are loading with doors open. If your interval data shows short, sharp peaks, a battery that trims them can pay where overnight storage doesn't. See demand charges and commercial solar batteries.
What does each state offer a cold store?
The federal STC discount applies everywhere. Since 1 October 2026 it covers eligible systems up to 1MW, and a system between 100kW and 1MW chooses between STCs and REGO certificates. The states add little for solar itself.
| State | What matters for a cold store |
|---|---|
| NSW | No rebate on solar panels. The Peak Demand Reduction Scheme gives businesses an upfront discount on batteries from 20 kWh to 30 MWh, larger when new solar goes in within 90 days. For a cold store with sharp peaks, this can change the battery answer. |
| VIC | Victorian Energy Upgrades gives an upfront discount on business solar systems between 30kW and 200kW, through an accredited provider. Larger systems can use its project-based activities. |
| QLD | No state rebate for commercial solar. Feed-in credits in the south-east are set by retailers, so check your contract before counting on exports. |
| SA | No state government rebate. Some councils, such as the City of Adelaide, run their own. Export value is especially weak, so size the system to what the site uses. |
| WA | No state rebate for business solar. The buyback scheme doesn't cover commercial systems, so the return comes from what the site uses. |
| ACT | No solar rebate. The Sustainable Business Program co-funds energy efficiency upgrades up to $10,000. Solar isn't a listed item. |
We haven't checked Tasmania or the Northern Territory yet, so nothing here applies to them. Full detail and dates are on commercial solar rebates.
What should a cold store send for a proposal?
Just one recent bill, every page. Using the NMI on it, the team gets your interval data, which shows the day and night split and when the peaks happen. You don't need to request anything.
If you know them, these help too. Mention them in the form:
- Refrigeration details: number of compressors, defrost schedule, any planned expansion
- Loading hours: door-open times change the load and the peaks
- Roof: many cold store roofs are insulated panels, and fixings must not break the insulation or vapour seal
Our guide on how to read a commercial electricity bill explains what's on it.
What to ask your installer
- How much of the solar do you expect us to use, and is that from our interval data?
- What does the system save at our real rate per kWh, not a typical one?
- How will the panels be fixed to an insulated roof, and who warrants the roof afterwards?
- Does our network limit exports, and what happens to the spare power at weekends?
- If you suggest a battery, what does it do to our demand charge, shown on its own line?
How much solar a cold store can use is in its interval data, and only your bill shows the rate it saves. Send a bill and an accredited installer prepares a costed proposal sized to how your site uses power. It's free, with no obligation.