With Kiwi household electricity bills skyrocketing this winter and set to double in the next five years, it’s no surprise that we have seen a massive surge in interest for home solar panels!

Solar energy systems will reduce your carbon footprint, slash your power bills, add value to your home, help you ride out price surges in winter, and, with solar battery storage, can provide security against regional power outages.

Overall, solar power is an excellent long-term investment for New Zealanders, especially if you’re installing a system that is bespoke to the energy needs of your household. So, how many solar panels does your home actually need?

Calculating the size of the solar energy system your home needs:

Home solar capacity

Before we delve into panel numbers, we need to talk about capacity. The capacity of a home solar system is noted with a kW (kilowatt) rating, which is the maximum amount of energy the system can generate at its peak output.

When it comes to solar energy capacity, bigger doesn’t necessarily mean better! To get the best value, the size of your system should closely match your household’s electricity usage, because buy-back rates are fairly low in NZ. It’s important to involve a solar professional in the decision process to assess your energy usage and provide an expert assessment of the capacity you require. Our team is always happy to help! Harrisons customers also have the added benefit of exclusive access to the highest buy-back rate of 18c per unit, so your solar capacity goes further with us.

If you think your energy needs will increase in the future because your family is growing or you are considering an electric car, a larger system will still be worth the long-term investment! In the meantime, you could consider a solar battery to store your excess power.

Quality is key

Higher-quality solar panels can deliver a higher power output. Choosing reputable solar panel brands and models (like AIKO) means you will need less panels to build the same size energy system - while they might cost more individually, you won’t need to buy as many, and they will take up less space. After years of research and testing, we exclusively partner with AIKO, which are the #1 premium solar brand in all key global markets, offer a credible 25-year warranty.

More sunlight could mean less panels

New Zealand experiences varying sunlight hours across different regions, with the highest exposure in areas like Northland, Auckland, Taranaki and Nelson. You might need slightly less solar panels in these areas than in other regions of New Zealand to generate the same output. That said, all of New Zealand has excellent solar potential. No matter where you are in the country, your system can pay itself off in less than 7-9 years!

3kW home solar system = 8-10 solar panels

A 3kW system is ideal for 2-3 person homes, especially if you mostly use low-energy appliances. A lot of families use 3kW systems to offset the bulk of their power bills during the off-peak season. It won’t cover all of your power usage, and can still pull a little from the grid, but your utility bill and carbon footprint will still be thanking you!

Depending on panel quality, a 3kW system requires 8-10 solar panels and uses a roof area of 15-20m2. A high quality 3kW AIKO solar system only requires 8 x 415w solar panels.

5kW home solar system = 12-14 solar panels

If your home has 4 or more people, or you want to become completely energy independent, a 5kW+ system is more likely to fit the bill - especially if you add a solar battery (like a Tesla Powerwall) to capture the maximum amount of energy output.

Depending on panel quality, a 5kW system requires 12-14 solar panels and uses a roof area of 25-30m2. A high quality 5kW  solar system only requires 12 x 415w panels.

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