Top 10 questions about Solar

Ask the Resident Builder

We know that hi-tech systems carry with them some pretty dense jargon, that’s why we’ve got The Resident Builder Peter Wolfkamp to run the rule over some of your more frequently asked questions and provide a simple guide to some of the more complicated technology.

Why choose solar panels?

By generating your own energy through solar panels, you reduce the need to buy electricity from your power provider; additionally, any surplus (“green”) energy the panels produce is then sold back to that same provider or stored in batteries for non-solar production times. These two factors work to drastically lower your household’s electricity bill. Solar units eliminate tonnes of greenhouse gas emissions a year, reducing your carbon footprint while improving the value and energy rating of your home

What is a grid-connected solar panel system?

With a grid-connected solar panel system, panels are wired to an inverter or inverters that convert the DC power generated by the panels to 230V AC household power, where it is then used to run any electrical appliance. Any power that the panels produce that you don’t use is sent back to the electricity grid. A smart meter measures how much electricity is drawn from or fed back to the grid, allowing you to be paid for any energy you feed back.

How effective is a solar system in terms of value for money?

Sunlight is a natural, clean energy resource, and with New Zealand’s three major cities, Auckland, Christchurch and Wellington, all receiving more than 2,000 hours of sunlight each year, there’s a lot of free, sustainable energy on which to capitalise. Once you have paid for the initial instalment of your solar power system, the energy that is generated is absolutely free.

How much roof-space is required?

The amount of roof-space required will vary depending on the size of the system you wish to install. For example, a 1.5kWp system will require about 10m2 of unshaded roof space. The system is modular, which means the panels can be arranged in the best way for the roof.

Are solar systems effective in winter?

Solar Photovoltaic Systems are not reliant on heat, simply sunlight and ultra-violet rays. Cooler sunny days actually provide higher production from the system however we must remember the sunlight hours are less during the winter. When designing a PV system, we take into consideration the change in seasons when estimating the annual energy production.

What happens at night?

Solar PV systems produce electricity only when they are exposed to sunlight, so at night you will need to either invest in battery storage or buy power from another source. The benefit of a grid-connected solar panel system is that your household will be powered naturally during the day and the grid can supply you with electricity at night.

How can I optimise the savings on my solar system?

To make the most of your savings, try doing things that require high amounts of power – such as heating the pool, doing the laundry, and taking showers – during the day when the solar panels allow you to produce your own energy. Try to decrease your night time power consumption, when you will not be producing your own power. Additional equipment like timers and controllers can assist in reducing night time grid use and shift power use to sunlight hours.

How long does an installation take?

Installation will depend on the size of the solar power system being installed but typically takes anywhere between 4 and 8 hours.

Does the orientation of the roof affect whether or not a home can install a solar product?

Depending on your power use lifestyle, the system’s optimal design and production will depend on your roof orientation. For example, north-facing is great for stay-at-home situations while east/west combinations may suit better where production is required more in the morning and late afternoon.

Solar power systems can be installed even on a flat roof. A mounting system can be installed to angle the panels so they collect the maximum amount of energy from the sun’s rays.

Is it possible to increase the size of a solar PV system in the future?

Increasing the size of your solar PV system depends on two factors: available space on your roof and additional capacity in your inverter. If there is sufficient space free for both, then you can increase the size of your system. If the capacity of your inverter has been reached, you could consider adding a second system to your roof.