It’s the question every hands-on, money-conscious homeowner asks: can I install solar myself and save on the labour? The honest answer for New Zealand is mostly no — the electrical heart of a home solar system is not legal DIY. But the picture isn’t black-and-white, and it’s worth knowing exactly where the legal line sits, what you genuinely can do yourself, and why the rules are strict.
The hard rule: mains and grid-tied work is prescribed
In New Zealand, electrical work on your mains-connected installation is prescribed electrical work — by law it must be carried out (or supervised and certified) by a registered electrician, who issues a Certificate of Compliance (CoC). Connecting a solar system to your home’s switchboard, installing and wiring a grid-tied inverter, and the AC side of any home system all fall squarely into this category.
That means you cannot legally:
- Connect solar panels or an inverter to your home’s mains wiring.
- Wire up a grid-tied system.
- Do the switchboard work to bring solar into your home.
This isn’t bureaucratic fussiness. These systems run at dangerous voltages, the DC side behaves in ways that catch out the untrained, and mistakes cause fires and electrocutions. The CoC is your legal proof — and your insurer’s — that the work was done safely and to standard.
Where there’s more freedom: extra-low-voltage off-grid
There’s a genuine exception, and it’s where most legal DIY solar lives. A self-contained, off-grid system running at extra-low voltage (ELV — generally up to 50 V AC or 120 V DC), not connected to the mains, is broadly more open for a competent person to work on themselves. Think a small 12 V or 24 V setup for a caravan, boat, shed, or simple cabin — panels, a charge controller, and a battery, all standalone and never touching your house wiring.
Even here, “legal” doesn’t mean “risk-free”. Batteries — especially lithium — carry real fire and chemical hazards, DC wiring still needs correct fusing and polarity, and the battery installation standard (AS/NZS 5139) and good practice still apply. So the freedom is real, but the responsibility is yours.
What you can always do yourself
Regardless of the electrical rules, parts of a solar project are open to a capable homeowner:
- Research and design decisions — sizing, choosing components, planning.
- Some preparatory and non-electrical work, depending on the job.
- For small ELV off-grid systems, building the DC side as above.
But the moment the system touches your mains or the grid, it’s electrician territory.
Why the rules are worth respecting
Beyond the law, two practical reasons make DIY on the mains side a bad idea even if you’re tempted:
- Safety. Solar DC can’t be switched off at the panel, runs at high voltage, and arcs in ways AC doesn’t. It genuinely kills and burns when handled wrong.
- Insurance and resale. Uncertified electrical work can void your house insurance and create problems when you sell. A non-compliant system is a liability, not a saving.
The labour you’d “save” is small against the risk — and a grid-tied system must have that CoC regardless.
The verdict
In New Zealand, the electrical core of a home solar system — anything connected to your mains or the grid — is prescribed electrical work that only a registered electrician can legally do and certify with a Certificate of Compliance. A self-contained extra-low-voltage off-grid system (a caravan, shed, or small cabin setup) is more open to a competent DIYer, though it still carries real hazards and standards. Know which side of that line your project is on — and for anything touching the house, hire the electrician. It’s the law, and it’s the safe call.
Get a free assessment for a system designed and installed legally and safely.
Sources: Prescribed electrical work and Certificate of Compliance requirements per the Electrical Workers Registration Board (EWRB) and the Electricity (Safety) Regulations; ELV limits and battery installs per AS/NZS 5139. Verify current rules before any work.