Research & feasibility
We read your interval data, model the array against your real load profile, and tell you the payback before you spend anything.
Feasibility →
Commercial & rural solar · Auckland, New Zealand
The cheapest power you’ll ever buy is the power you don’t.
The Green Valley studies, designs, supplies and builds solar systems for New Zealand businesses, farms and growers — from the first look at your power bills through to grid connection sign-off.
- Where we work
- Auckland, Waikato & Northland
- What we install
- 615–640 W n-type bifacial modules
- Typical Auckland yield
- ~1,250 kWh per kWp per year
- Who does the work
- EWRB-registered electricians
One team from the power bill to the meter change.
Most solar disappointment traces back to a system sized by roof area instead of load, or a handover with no one accountable afterwards. We keep the study, the design, the supply and the build under one roof so nobody can point at anyone else.
Design & engineering
String layout, structural check, inverter selection, cable routes, protection and export limits — drawn and documented.
Design →Equipment supply
Tier-one modules, AS/NZS 4777.2 inverters and engineered mounting, landed and warranted in New Zealand.
Equipment →Installation
Roof works, structural mounting, DC and AC, grid application, commissioning, and a monitoring platform you actually get logins to.
Installation →
The economics
A unit you don’t buy is worth more than a unit you sell.
On a working site the array and the load run on the same clock. Refrigeration, compressors, irrigation, packing lines and HVAC all draw hardest through the middle of the day — which is exactly when the modules produce.
Everything in the shaded zone is electricity you consume as it is generated. It replaces power you would otherwise have bought at your full retail rate, lines charges and GST included. Everything above the load line is exported, at a buy-back rate your retailer sets and which is usually a fraction of what you pay to import.
That gap is the whole business case, and it is why we size an array to your load rather than to your roof area. Past a certain point, extra capacity just sells cheap power back to the grid.
Why on-site solar pays on a working site
Clear-day output vs. a typical weekday load · Auckland
Array output
Site load
Used on site as generated
Every kilowatt-hour in the shaded zone replaces one you would have bought at your full retail rate — lines charges, levies and GST included. Anything above the load line is exported at a much lower buy-back rate. Sizing the array to the load, not to the roof, is where the return comes from. Illustrative profiles.
Sites that use power while the sun is up.
Solar rewards daytime load. Irrigation, refrigeration, milk cooling, packing lines, compressors, chillers and office HVAC all run on the same clock as the array — which is exactly the type of site we work on.
Farms & rural
Dairy, irrigation and livestock
Milk cooling and vat refrigeration, effluent pumps, irrigation and shed load — the heaviest draws land squarely in the middle of the generation curve.
Rural solar →
Commercial & industrial
Warehouses, coolstores, packhouses
Big, simple, unshaded roofs above a steady weekday load. Usually the best return per dollar of any site type in the country.
Commercial solar →
Structures
Carparks, canopies and shade
When the roof is full, taken or unsuitable, the yard is next. Canopies generate, shelter stock or staff, and carry EV charging.
Canopy systems →
Start with a number you can argue with.
Move the sliders to see roughly what a system for your site would look like. This is a back-of-the-envelope model, not a quote — but it is the same arithmetic we start a real study with.
Not sure of your daytime share? Most packhouses, coolstores and workshops sit between 60% and 80%. Offices and retail are usually 50–70%. Dairy sheds with two milkings are lower, around 40–55%.
- Indicative array
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- Modules at 640 W
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- Roof or ground area
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- Annual generation
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- Estimated annual saving
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- Simple payback range
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Modelled at 1,250 kWh per kWp per year for a well-oriented, unshaded Auckland array, an installed cost of $1.40–$1.90 per watt and a 12 c/kWh export rate. Indicative only — it ignores your tariff structure, shading, roof condition, network export limits and tax treatment, all of which we model properly in a feasibility study.
Equipment
n-type bifacial glass-glass, as standard.
Our reference module is the JA Solar DeepBlue 4.0 Pro JAM66D45 LB — 615 to 640 W, 132 half-cells, double glass, up to 23.7% module efficiency.
- Bifacial 80% ±5%. The rear face harvests reflected light — worth real energy on light roofs, ground mounts and canopies.
- 1% first-year degradation, 0.4% a year after that. Still guaranteed at 87.4% of nameplate in year 30.
- 12-year product warranty, 30-year linear output warranty. Backed by IEC 61215 and IEC 61730 certification.
- Built for weather. 5,400 Pa front load, 2,400 Pa back load, IP68 junction box, anodised aluminium frame.
Eight steps, in this order, every time.
Solar projects go wrong in predictable places: an undersized study, a roof that won’t take the load, and a grid application started too late. Our sequence is built around those three.
01
Bills and data
Twelve months of invoices and, where the meter supports it, half-hourly interval data. This sets the load profile everything else is sized against.
02
Desktop feasibility
Yield model, self-consumption estimate, indicative capital cost and payback. Delivered as a written study, not a sales sheet.
03
Site survey
Roof structure and cladding, purlin spacing, switchboard capacity, cable routes, shading, safe access and anchor points.
04
Design and proposal
Layout, single-line diagram, structural verification, inverter and protection selection, fixed price and programme.
05
Consent and grid application
Distributed generation application to your lines company, building consent where required, and export limit agreement.
06
Supply
Modules, inverters, mounting and balance of system landed, checked and staged to the programme.
07
Installation
Mounting, DC, AC, switchboard works and metering. Grid-tied electrical work by EWRB-registered electricians.
08
Commissioning and handover
Testing, certification, monitoring set up in your name, an as-built pack, and a maintenance plan.
Next step
Find out what your roof is worth.
Send us twelve months of power bills and a roof plan. We come back with a yield model, a layout, an indicative price and an honest view on whether the numbers work.