Sue Brown is CEO of New Zealand Clean Energy.


The installation of PV (photovoltaic) panels onto New Zealand homes has become increasingly popular as people realise the value of turning daylight into electricity to reduce their power bill.

New Zealand gets its fair share of sunshine hours, so it makes good sense to harness that power, and rapid advances in the technology have put solar power generation firmly within reach of many households.

It will pay at this point to understand that PV panels will work where there’s daylight; unlike solar water heaters, they don’t need direct sun to make a significant contribution to reducing power bills.

Many customers have found that they have been able to reduce their monthly power bill by a half or even better. This equates to a return on capital invested of at least twice the return of it sitting in a savings account, so it represents a smart use of capital.

As with most fast growth industries, the category has attracted so many different potential suppliers that it’s difficult to know how to choose between their offerings.

Since they all look about the same, should you choose the cheapest?

My clear view is that cheapest isn’t the best way to go, since you do get what you pay for. You are looking at equipment with a projected useful life of over 25 years, so it will pay to look well beyond the short-term attractiveness of a cheap price. Here are some things to look for:
Familiar panel brands
As a rule, big and familiar brands are the safest. These companies have reputations to safeguard and will be more willing to participate in a remedying conversation if one is needed. You might get lucky with a cheaper, unknown panel but they often turn out to be more expensive in the long run. You won’t regret buying quality from a reputable supplier, and spread over 25 years, the difference in cost is negligible. I think having that peace of mind makes sense.
High quality inverter
The inverter turns the DC power generated by the panels to the AC power that households require. It’s the heart of a good system. You’ll need one with a wide enough voltage range, with a low start-up voltage, to be able to accommodate the addition of more panels to your system if you decide to expand in the future.

It should have a built-in Wi-Fi system for web-based system monitoring.

It should run at a cool operating temperature and It should have local service backup.
Reliable warranties
The hardware in panels should be warranted for at least 10 years. Panels should be warranted to produce at least 80 percent of their performance after 25 years operation. They need to be able to work in New Zealand’s wide temperature range, so look for the ability to operate between at least -20C to +60C.

A five year warranty on inverters is the norm. Local back-up to service all warranties is essential.
Reputable installation
There’s zero point in having the best hardware unless it’s attached to your home properly. All of New Zealand is subject to very high wind-loadings and some localities have to deal with extreme weather events like heavy snow, tornados or torrential rain from time to time, so having the correct fixings is key.

Having panels with glass that has the strength to bear the weight of snow is key.

Look for Warranties. Look for reputable installers with a good knowledge of building. Look for plenty of experience – you don’t want them learning their trade on your installation.
Look for industry accreditations
Reputable system suppliers and installers will be members of organisations like the Solar Energy Association of New Zealand (SEANZ) or the Australian Clean Energy Council. They have codes of conduct for members’ operations.

Installing a PV power-generation system is a great way to reduce power bills. It’s comforting to know what your power will be costing in 10 and 20 years’ time. It’s a great way to add value to a home. And it gives a good enough return on the capital invested to make it a worthwhile investment. It’s not a particularly difficult decision.

What is more difficult is deciding which system and supplier to use since the offers are decidedly not all the same. My view remains that buying the highest quality you can afford will serve people best in the long term.

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