The short answer. Price the parts and the labour together, not just the parts. A DIY build usually wins on the parts list by a bit, and then gives it all back in electrician hours, an enclosure, busbars, fusing and cable. If you are an electrician or an experienced installer, build it. If you are a homeowner, a builder, or anyone whose day job is not this, buy the cabinet and spend the time you saved on the rest of the project.
What people compare, and what they should compare
Almost everyone starts by pricing an inverter, a battery and a solar controller, adding it up, and comparing that number to a cabinet price. That is not the comparison. The cabinet price includes the enclosure, the busbars, the DC cabling, the fusing and circuit protection, the mounting, the weatherproofing, and crucially the design and configuration work that has already been done and tested.
The honest version of the DIY column has all of that in it too, plus the hours to put it together. Once it does, the two numbers end up a lot closer than the first pass suggests, and the cabinet is often ahead.
Side by side
Building your own compared with a pre-wired Energy Hub
| What matters | Build your own | Energy Hub |
|---|---|---|
| Parts cost | Usually a bit cheaper if you shop well | Fixed price, everything included |
| Electrician time on site | A day and a half to two days for design, wiring, configuration and commissioning | None if it plugs in, a few hours if AC wiring into the building is needed |
| Who owns the design | You, or whoever you paid to spec it | Us, already tested on the bench before it ships |
| Enclosure and weatherproofing | Source separately, or build a shed for it | Aluminium cabinet, designed to live outside |
| Warranty when something plays up | Each part has its own, and suppliers can point at each other | One system, one place to ring |
| Certificate of Compliance | Required, and the electrician is certifying work they have to understand from scratch | Supplied with the cabinet. If AC wiring is needed, the electrician certifies the connection, not a build |
| Timeline | However long the slowest part takes to arrive, then book the sparky | Lead time on the cabinet, then a short install |
| Expandable later | Depends entirely on how it was designed | More battery and more solar without replacing the cabinet |
The hours people forget
If you have not done one before, this is roughly what sits behind the words "and then wire it up".
- Mounting the inverter, the controller and the battery so they are serviceable, ventilated and not in the weather.
- DC cabling, busbars, lugs and crimps at the right size for the current, with the right fusing and circuit protection at both ends.
- Configuring the inverter and the solar controller for the battery you have actually bought, not the defaults it shipped with.
- Getting the battery communications talking to the inverter and the monitoring, which is the step that eats the afternoon.
- Testing it under load, checking the changeover behaves, and documenting it for the CoC.
None of this is difficult for someone who does it regularly. All of it is slow for someone who does not, and the configuration step is where most of the support calls come from.
When building your own is genuinely the better call
Build it yourself if
You are a registered electrician or an experienced installer. You will do it faster than our lead time and you will know exactly what you have got.
The site is unusual. Odd voltages, an existing generator to integrate, three phase, a shed that dictates a layout no standard cabinet fits.
You already own half the gear. If there is a good inverter on the wall already, replacing it with a cabinet is throwing away money.
The build is the point. Some people want the project. That is a perfectly good reason and we will happily sell you the parts.
Buy the cabinet if
Your trade is something else. Builders, farmers, tiny home owners, people managing a project rather than doing the wiring.
You want one warranty. One supplier, one number to ring, no arguments about whose component caused it.
The site is remote. Getting a sparky back twice because something was not configured right costs more than the difference.
You want it done this month. A tested cabinet and a short install beats chasing five suppliers and a diary.
What the Energy Hub actually is
A pre-wired aluminium cabinet with a Victron inverter, SOK batteries, solar controller, busbars, DC cabling and circuit protection already in it, bench tested before it leaves us. It is designed to be installed outside, so it does not take a cupboard off you. There is no programming and no commissioning on site. It comes with a Certificate of Compliance and 32A AC plug connections: caravan style on the Mini, PDL 56 Series or hard wired on the Midi. Mount it, connect the solar, plug it in and turn it on. If the job needs AC wiring into the building, your electrician does that part.
The Mini comes in four standard builds with firm pricing, from 3kVA and 5kWh up to 5kVA and 10kWh with cellular monitoring. The Midi is the larger one for full time off grid houses and light commercial. It is built to order around a Victron inverter sized to your loads, with 10 to 30kWh of storage. Our example builds use a MultiPlus 48/5000 or a MultiPlus-II 48/8000, but a different inverter, three phase or generator input are all options.
Do you need an electrician?
It depends on whether AC wiring is needed. The cabinet is supplied with a Certificate of Compliance and can connect through 32A plugs, so if it is feeding a plug-in load or a building already set up with an inlet, there may be no electrical work to do on site.
If it has to be wired into a switchboard or the building's fixed wiring, that is mains voltage work, and in New Zealand it has to be done and certified by a registered electrician, exactly as it would for a DIY build. What the cabinet removes is the design and configuration work, which is the expensive, slow, easy-to-get-wrong part. The connection itself is a straightforward job for any competent sparky.
Common questions
Is it cheaper to build my own?
On parts alone, usually by a small margin. Once the electrician hours, the enclosure, the busbars, the fusing and the cable go in the column, the gap closes to very little and often disappears entirely.
Do I still need an electrician for a cabinet?
Only if AC wiring is needed. The cabinet comes with a CoC and can plug in, so some installs need no electrician at all. If it has to be wired into the building, a registered electrician does that connection and certifies it. Either way, you avoid paying anyone to design, wire and configure the system itself.
How long does commissioning a DIY system take?
Allow a day and a half to two days of electrician time for a typical build. A cabinet that plugs in needs no commissioning, and one that needs AC wiring is usually a few hours on site.
What is the warranty difference?
With a DIY build every component carries its own warranty from its own supplier. With a cabinet the whole system is covered as one unit, so there is one place to call when something is not right.
Can I expand a cabinet later?
Yes. They are built on the Victron platform, so more battery and more solar can be added without replacing the cabinet.
Can I buy the parts from you and build it myself?
Of course. We stock the batteries, the Victron gear, the cable, the lugs and the circuit protection, and we are happy to talk through a parts list before you order.
Not sure which way to go?
Tell us what you are powering and how the site sits. We will give you an honest answer, including when that answer is a parts list rather than a cabinet.
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