For most New Zealand homes the honest answer is yes — provided your power bill is high enough and you use some power during the day. A typical grid-tied system pays for itself in about six to eight years and then keeps generating, largely for free, for another two decades. But “most homes” is not “every home”, and the difference between a great result and a mediocre one comes down to a few things you can actually check. This guide walks through the maths so you can tell which side of the line your home sits on.
The short answer
If your monthly power bill is over roughly $200, you own your roof, and someone is home using power during daylight (or you can move big appliance use into the day), solar is very likely worth it. In that situation a typical 6.6 kW system saves most NZ households somewhere around $1,500–$2,300 a year and pays back in six to eight years without a battery.
If your bill is small, your house is empty all day, your roof faces south or is shaded, or you are about to move — the case is weaker, and “not yet” can be the right answer. The rest of this page explains why.
How solar actually saves you money
This is the part most people get wrong, and it is the single biggest driver of whether solar is worth it.
Using your own power beats selling it
Your solar saves you money in two very different ways:
- Power you use yourself replaces power you would otherwise buy from the grid. In New Zealand the average residential price is about 39.3 cents per kWh (MBIE’s official figure, early 2026), so every unit you self-consume is worth around 39c to you.
- Power you export (send to the grid) earns only the buy-back rate your retailer pays — typically 8–17 cents per kWh.
So a unit of solar you use yourself is worth roughly two to three times more than one you export. The households that get the best return are not the ones with the biggest systems — they are the ones who use the most of their own generation.
What “self-consumption” looks like
Without a battery, most homes use 30–50% of what they generate and export the rest. With a battery that rises to 70–90%, because evening load is covered by stored daytime solar. Lifting your self-consumption — by running the dishwasher, washing machine, hot water and EV charging while the sun is up — is the cheapest way to improve your return, because it shifts units from the low export rate to the high retail rate.
A worked example
Numbers make this concrete. Consider a typical home with a 6.6 kW system:
- System cost: about $14,000 installed.
- Generation: roughly 9,200 kWh a year (Auckland; a little less further south).
- Self-consumption: say 35% for a household that is out during the day — about 3,220 kWh used directly. At 39.3c that avoids about $1,265 of power you’d have bought.
- Export: the other ~5,980 kWh sold at, say, 12c buy-back earns about $718.
- Annual saving: roughly $1,980.
- Payback: $14,000 ÷ $1,980 ≈ 7 years — after which the system keeps producing for 20+ more.
Now shift more usage into daylight and lift self-consumption to 50%: the same system saves closer to $2,300 a year, and payback drops nearer six years. Same hardware, better habits — that’s the lever.
What decides whether it’s worth it for your home
1. The size of your power bill
A bigger bill means more expensive grid power to displace, and a faster payback. Below about $150 a month there is simply less to save, and the maths gets marginal.
2. When you use power
A home with someone in it during the day — or with shiftable loads like hot water and EV charging — captures far more value than an empty house. If almost all your usage is after dark, a no-battery system will export most of its generation cheaply, and you should either plan to shift usage, add a battery, or expect a longer payback.
3. Your roof and region
North-facing, unshaded roofs generate the most; east/west still works and can suit morning/evening usage. South-facing or shaded roofs cut output. Region matters less than people assume — Auckland produces around 1,390 kWh per kW a year and Christchurch around 1,340 — but the southern seasonal swing is larger, so winter output is lower.
When solar isn’t worth it (yet)
Be honest about these:
- A small bill and an empty daytime house — the savings won’t justify the spend.
- A poor roof — heavily shaded, south-facing, or due for replacement (you don’t want to remove panels in a few years).
- You’re moving soon — solar can lift resale value, but you won’t capture the operating savings yourself.
The 2026 changes that improve the case
The economics are shifting in solar’s favour. From 1 July 2026, the Electricity Authority requires large retailers (those with 5%+ market share, such as Contact, Meridian and Mercury) to offer time-of-use pricing and time-varying buy-back — plans that pay a genuinely better rate for power you export at peak times (evenings), when the grid needs it most.
For solar owners this matters in two ways: cheaper off-peak power to import, and a more rewarding rate for exporting at the evening peak. It also strengthens the case for a battery, which can store cheap or self-generated daytime power and release it into the high-value evening window.
Does solar add to your home’s value?
Increasingly, yes. New Zealand property research now shows solar being reflected in sale prices — estimates range from around 1.3% up to 3–4% (roughly $21,000–$28,000 on a $700,000 home in one study). Surveys also find a majority of buyers would pay more for a home that already has solar. It’s not a reason to install on its own, but it softens the “I might move” objection.
How to get a number for your home
Ranges and worked examples are a starting point, not your answer — your bill, your daytime usage, your roof and your region all move the result. The honest next step is to model your numbers: the EECA solar calculator is a good neutral starting point, and our free assessment models system size, cost, savings and payback for your specific address.
Sources: MBIE electricity price monitoring; Electricity Authority — solar/peak-export reforms; EECA solar for homes. Figures are 2026 estimates and vary by home.