Solar for cold stores and packhouses: refrigeration is the load
Michael Wilkins · Updated 11 July 2026
The short answer
Cold stores and packhouses suit solar because refrigeration, up to 85 percent of their energy use (EECA), runs through daylight and peaks in the warm months with the sun. The year-round refrigeration base load keeps self-consumption high, which is what makes the payback work; a 100 kW system costs roughly $140,000 to $180,000 installed in 2026.
Refrigeration is a near-perfect solar load
A cold store is a refrigeration business, and refrigeration is close to a perfect solar load: it can be up to 85 percent of site energy use, it runs through daylight, and it works hardest in the warm months when the sun is strongest. That is why coolstores, packhouses and food processors are among the strongest commercial solar cases in New Zealand.
Year-round load beats a seasonal peak
A packing line runs for a few busy weeks; a cold store runs every day of the year. That steady daytime base load is what makes refrigerated sites pay: the system serves real demand almost every daylight hour, so self-consumption stays high and little generation is wasted on low-value export. Self-consumed solar avoids the 25 to 45 cent retail rate; export earns only 7 to 17 cents.
Designing around the cold chain
Panels usually go on the coolstore or packhouse roof, or on structure alongside, and the work is programmed around your operating calendar so the cold chain is never at risk. A battery is a separate decision for outage resilience, not a requirement for the savings. The full method is in our feasibility study guide.
For region-specific numbers, see our Canterbury cold store and packhouse page or the Central Otago orchard and packhouse page, or run a first estimate in the calculator below.
Run your own numbers
Conservative assumptions, fully disclosed, no contact details needed.
Your indicative numbers
Conservative, ex GST, modelled not promised
System size
72 kW
Sized to your daytime load
Installed cost
$112,320 to $152,640
Confirmed with certified installers
Investment Boost, year one
about $7,419
A 20% immediate tax deduction, worth this in cash at the 28% company rate. Not a discount.
Estimated annual saving
$18,662 to $22,118
80% of generation used on site
Indicative payback
5 to 7.5 years
Net of the Investment Boost benefit
Asset life
25+ years
Panels keep producing long after payback
Bank green business loans: 1.0% for 3 years
Your current bill
$4,000/month
Loan repayment
$2,257/month
Estimated saving
$1,699/month
The loan caps at $80,000, so the repayment shown covers that portion; the remainder is financed separately. The full financing stack is part of the feasibility study.
On these numbers the monthly repayment of $2,257 sits at or below your current bill of $4,000 while the loan runs, and the power keeps getting cheaper after it ends.
How this is modelled (assumptions v2026-06-v3)
- Power valued at $0.25 to $0.30/kWh ex GST (savings are never valued at the top of the commercial tariff range).
- Export credited at $0.08/kWh, the conservative end of current buy-back rates.
- Installed cost interpolated from 30 kW ($1,800 to $2,600/kW) down to 500 kW ($1,100 to $1,500/kW), 2025/26 working ranges.
- Canterbury yield modelled at 1200 kWh per kW per year.
- Self-consumption capped by your daytime usage profile and held below typical vendor claims; sizing targets 90 percent of daytime load.
- Investment Boost stated as the year-one cash value of the 20 percent immediate deduction at the 28 percent company rate. It is a tax timing benefit, not a discount.
- No power price escalation and no panel degradation in simple payback; omitting escalation outweighs degradation, so the net effect is conservative.
Indicative only; not financial or tax advice. The feasibility study models your site from twelve months of actual bills.
Get these numbers checked properly
The real model is built from twelve months of your bills. Send your details and we will do it for you; we reply within one working day, no obligation.
Straight answers
Why do cold stores suit solar so well?
Refrigeration can be up to 85 percent of a coolstore or packhouse's energy use (EECA), it runs through daylight, and it peaks in the warm months when solar output peaks. That load shape is close to the best match there is for solar, which is why refrigerated sites are among the strongest commercial cases in New Zealand.
Does year-round refrigeration help the payback?
Yes, more than a seasonal peak. A cold store draws power every day of the year, so a solar system serves a steady daytime base load rather than a few busy weeks. That keeps self-consumption high, the share of generation used on site, which is what makes the payback work.
What does a packhouse or cold-store system cost?
It scales with the refrigeration load. A 100 kW system runs $140,000 to $180,000 installed at 2026 pricing and 250 kW around $275,000 to $375,000, with per-kW cost falling as size rises. The Investment Boost deduction returns about 5.6 percent of the cost in year-one tax cash for a company taxpayer.
Do I need a battery to protect the cold chain?
Not to save money; refrigeration is a daytime load solar serves directly. A battery is worth modelling where outage resilience has real value, since a standard grid-tied system shuts down in an outage for line-crew safety and will not back up your coolstore on its own. We model storage separately so the numbers decide.
Does solar work for produce and seafood processing too?
Yes. Any site where refrigeration or freezing dominates the load, packhouses, coolstores, seafood and meat processing, dairy factories, shares the same daytime, warm-season demand that solar serves well. The stronger and steadier the refrigeration base load, the better the case.
For your industry and region
More from this guide
- Commercial solar in New Zealand: costs, payback and how to decide
- Investment Boost on solar: what the 20 percent deduction is actually worth
- Solar buy-back rates for businesses: export is not the prize
- What a commercial solar feasibility study includes, and when you need one
- Solar finance for NZ businesses: loans, PPAs and what actually stacks
- Solar power for dairy farms: the honest numbers
- Solar for wineries and vineyards: Marlborough to Central Otago
- Solar for irrigation: the best daytime load there is
See what solar does for your refrigeration load
The calculator models self-consumption first, on conservative assumptions. Two minutes, no contact details, or send a year of bills for the full study.