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How Harrisons can help you choose the right solar system for your household’s needs

There are a number of factors that determine the perfect solar system for a New Zealand home – and taken altogether they create an equation where systems have to be individualised to suit a specific household’s needs.

We spoke to Harrisons Solar technical advisor Cyril Marychurch about the variety of systems and versions on offer, and which factors are the most important when it comes to choosing domestic solar generation.

“When our solar energy experts visit a home, they can’t presume the reason why that person wants to get solar – everyone has their own drivers,” he said. “That means we can’t throw everyone into a one-size-fits-all solar system.

“We generally have a solar system that’s right for 90% of the people we go and see – it’s then a matter of calculating how we can use the technology so that it best fits each of them.”

The main factors are:


Probably the main reason people contact Harrisons Solar for a solar system is that they want to make a dent in large power bills. This saving, however, is entirely dependent on how you use your power.

The typical annual household consumption for a medium family is around 8000kW, which, on paper, would be almost entirely covered by a large 5.5kW system.

But, if that family’s power consumption is largely outside of daylight hours (for example, two working parents with school-age children) then a large system would be mostly redundant. Alternatively, if it’s a home-based business or there are pre-school children at home most of the day, then the power is being used as the system is converting sunshine into electricity.

The financial benefits of having solar which can be compounded by making technological or lifestyle changes (for example, heating water during the day or choosing to work from home), can also be cancelled out by households who see the free extra power simply as a bonus.

So when it comes to the first power bills, “We often find people see the system as a “use all you can” and their consumption actually goes up. If someone wants to reduce their power bill then what comes into play is how big their power bill is, when they it, and their overall lifestyle.”


Bigger doesn’t always mean better when installing a domestic solar system – it’s more about smart thinking. For example, Cyril said he knows he could fit 300sq m of panels on his house if he wanted to, but he doesn’t have that many because he knows how much power he uses and how much he needs to generate.

“When sizing the system, we work out how much power the household needs and then work back to the number of panels required.”

As a general guide, Harrisons calculates:

·Lower power users would pay between $4900 and $7000 for a small system and generate between $695-$750 worth of power in the first year.

·Average power users would pay between $7000 and $10,000 for a medium system and generate between $1200-$1300 worth of power in the first year.

·High power users would pay more than $10,000 for a large system and generate more than $1800 worth of power in the first year.

Because of the 25-year life of a system, those savings ought also to play a role in determining the right system for a household.

Harrisons Solar experts can also explain how the systems are scalable so that a small system can be upgraded with extra panels and extra generating capacity, if required.

At Harrisons, we never want the price of a solar system to be a barrier, so we have a range of payment options available to our customers.

Are batteries for everyone?

Most of the talk in solar at the moment is around battery technology – how they’re becoming more powerful and less expensive. At Harrisons, we see them as the future of smart homes and central to supplying New Zealand’s domestic energy requirements.

If you want to completely eliminate your power bill, you will need to maximise solar self-consumption during daylight hours and add battery storage for the rest of the time.

A retired couple, however, who are at home during the day are likely to use most of their generated power and not charge up their battery.

“It’s all about knowing how much of that free power you can use during the day, so for a retired couple they would probably go into 5pm every day with a flat battery and it wouldn’t be efficient,” Cyril said.

“Some people, on the other hand, just want a battery for back up and in case of power cuts. We certainly have some customers who don’t want one for everyday use, they just want it filled up and the plug put in so it’s not emptied and then know that it’s there in the case of an emergency.”

The likelihood that batteries will become the norm in coming years, means it is important to make sure your solar system is compatible – something Harrisons Solar will ensure with all our systems.

Individual reasons for getting solar

Although the majority of Harrisons Solar clients are keen on the cost savings of generating their own power via solar, there are plenty of others who come to us for other reasons.

Cyril said these included people concerned about the environment who wanted solar as a way to reduce their overall energy consumption and those who wanted to take control of their energy usage back from the generating and lines companies.

Because solar attracts some of the biggest names in innovation (such as Tesla and LG), Cyril said there were also clients who wanted the latest in technology.

“Some people with north-facing roofs aren’t always keen to have their panels on sight but when I said that to a client the other day when I realised you’d be able to see the panels every time you drove up the driveway, he said that’s exactly what he wanted,” Cyril said.

“For some people, the panels are a status symbol and a sign that they’re thinking about how they’re generating their power.”

Before choosing a solar system or deciding whether battery storage is suitable for your home,contact Harrisons Solar to book a consultation with one of our experts.

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