Frequently Asked Questions
How many solar panels are required to run a house?
A typical house will have around 10- 18 panels. This works well to reduce using electricity from the grid.
For best results, get in touch with us to conduct a survey on your house to see how many solar panels will work best for you.
How much do solar panels cost in New Zealand?
A typical cost for solar panels on a house in New Zealand is between $9,000(10 panels) and $15,000(18 panels) including GST.
Are solar panels worth it in New Zealand?
Yes. Solar can be a really good way to save money, reduce electricity bills and be more environmentally friendly at the same time. See our blog to learn more about how solar panels are worth it.
How do solar panels work?
When photons in the Sun’s light hit solar panels, electrons in the solar cells become excited and produce DC electricity.
Your house runs on AC electricity. The inverter is used to convert DC to AC so the power can be used in your home. Check out our blog post on how solar panels work for more information.
Will my solar panels work at night?
Solar panels will only work if the sun is out. If you want to use energy from solar at night. You’ll need a battery to store the power generated during the day. You can find more about batteries here.
Will my solar panels work during cloudy weather?
Solar will continue to work during cloudy weather, just with less output. The thicker the clouds, the less power your panels will produce. The clearer the sky is, the more they will produce.
Will my solar system require maintenance?
Very little! The only regular maintenance needed is to check your panels every six months to ensure they are clear from twigs, leaves and other obstructions. for optimal performance, you should clean them every couple of years.
We do recommend getting an installer to check over the system once every five years, to make sure everything is working well.
Will installing solar panels damage my roof?
Solar panels have been shown to extend the life of a roof, due to protecting it from sun, wind and rain.
Most solar racking systems use the purlin screw holes already in your roof. The only other hole will be for the cabling into the roof space.
Reputable solar installers are experienced in working on roof’s and will install solar with no damage to your property.
Are there any government incentives for solar panels?
At this point in time, there is no government incentive for solar PV. Incentives for electric vehicles are currently being considered by the government.
Does my roof angle affect how much my solar panels will produce?
Yes, it does! Solar panels work best when the Sun’s rays are perpendicular to them.
Lower angle panels work best in summer when the sun is high in the sky. Higher angle panels work best in winter when the sun is lower in the sky.
Generally, if you have a steep roof, this is good for all year round energy production. If you have a lower angle roof, we can add extra panels or tilt the panels up at a steeper angle. A system can be designed to suit almost any angle of the roof.
Will my panels store energy?
No. To store energy generated from solar panels you will need a battery system.
Currently batteries don’t represent a great return on investment, and are only specified if your priority is optimum system environmentally or you would like to protect yourself from power cuts. You can find more about batteries here.
If the grid goes down, will I still have power?
No. A standard grid-tied solar system will shut down during a power outage. This is to protect workers when fixing the power lines. If you carried on producing power, there is a risk that some electricity would make it out to the grid, possibly electrocuting lines company workers.
If you do want your power to remain on during an outage, you should consider a system with batteries and backup.
When will I need to replace my solar system, what does my warranty cover?
Solar panels and inverters now come with long warranties.
The warranties are broken down into manufacturers and performance warranties. Manufacturers warranties cover any defects in the panel. They are typically around ten years. Performance warranties cover your panels energy production. Most say that the panel should produce 80% of what they did originally by the end of the warranty, which is typically 25 years.
Inverter warranties differ quite a bit. Entry-level inverters typically have a five-year warranty. High-end inverters typically have a 10-year warranty, with the option to buy a longer warranty. It’s important to use a good inverter with good support. This part of the system does a great deal of work over its life converting DC to AC.
A Warranty is only as good as the manufacturer issuing it. At Dunedin Solar we only use products from manufacturers we can trust will be around to see out the warranties and give us great support.
It’s no good getting solar panels with a 25-year warranty if the company is gone in five years!
My roof doesn't face north, will solar panels still work?
Yes. North facing solar panels will produce the most total energy. But its not always the best. A long time ago when power companies paid a lot for your excess power. It made sense to point your panels straight North.
This was because it didn’t matter if you used your energy or sent it to the grid. It was worth the same. Now with lower feed-in rates, it’s much more economical to use your solar power yourself. Therefore North may not be the best aspect for you.
If you use power in the morning, evening and are not using power around midday. An East or West array could suit you. For systems that include battery storage. It will matter less at what time of day you are producing power, as the battery will even things out. We can design a system to suit most aspects, no problem.
Is Mono-crystalline better that Polycrystalline?
They’re almost identical. There’s no need to worry about differences in performance between mono- and poly- crystalline panels. When comparing panels of the same rated power output, there is currently no practicable difference in the performance of these two technologies.
Should I get a solar system with a battery?
An interesting debate. Which hinges on what you want from your solar system.
For the highest return on investment, at this point in time, it’s probably best not to install a battery. We’d suggest waiting a couple of years for the price of batteries to come down, then add one to your system.
If backup power is valuable for you, or want power during a power outage then a battery might be a good investment.
We are starting to see a change in how electricity retailers buy and sell electricity. In the not too distant future, you will be able to store your solar power in batteries and sell to the power companies when they need it. This will make the investment in batteries really attractive.
I want to go off grid, can I?
Off-Grid is an entirely different affair than solar with batteries. An off-grid system has to be carefully designed to meet the energy demand of the house. There is no grid to help if more power is needed than available.
Generally, an Off-Grid system will have several days worth of battery storage built-in. This ensures power will still be available after a few days of bad weather.
A backup generator is usually built into the system. If you already have a grid connection, it’s more economical to stay connected and install solar with a smaller battery, than go off-grid. If you are far away from a grid connection, it probably makes sense to go off-grid, rather than pay to get mains power there.
Talk to us about this. We can help you make the right decision.
What will be the return on investment on my solar panels?
The answer depends on how well you manage your system. The more solar power you use directly while the system is producing, the better the return will be. This is called self-consumption.
Say we pay $0.30 for per kWh imported and $0.08 for the energy we sell back to the grid.
Let’s say our system produced 100kWh
If we had 100% self-consumption, our energy would be worth $30 (100kWh x $0.30)
If we had 40% self-consumption, our energy would be worth $16.80(40 x $0.30 + 60 x $0.08). 60% of the energy would be exported at a lower rate.
This is where it pays to install a well-sized system. A system designed to give you a higher self-consumption rate will give you higher returns.
A typical ROI for a system would be between 7 and 10 years. Once the investment is paid off. The panels will continue to produce energy for at least the next 20-30 years. Everything after the initial 7 to 10 years, you will be making money!
If you have any more questions or are looking at solar panels, fill in the form below and one of our designers will be in touch within 48 hours.