• When purchasing a solar system, don’t make the mistake of thinking ‘one size fits all’
  • To size your solar panel system, calculate how much electricity you use and when you use it
  • A typical Australian home uses approximately 15-20kWh per day, which equates to a 5kW system
  • kW measures power, kWh measures energy

One of the most common questions our solar consultants and solar engineers get asked is: “How many solar panels will I need to power my home?”

Ladies and Gentlemen, look no further! At Venergy, we’re here to help.

While we do recommend that you speak to one of our expert consultants who will look at your roof layout, electricity consumption, and other factors to provide you with a free personalised recommendation to best suit your solar needs, here is a quick start guide.

To book in a free consultation with one of our experts, click on the link below.

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Sizing your solar panel system

In order to figure out the size of the solar power system you need for your specific circumstances and how many solar panels you will need, here are two things to consider:

  • Look for your daily energy usage. The easiest way to know your current energy usage patterns is by reviewing your energy bills. Collect your electricity bills over the past year or so and calculate your average daily energy use.
  • Sunshine hours. It is an obvious rule that solar panels need sunlight to work. But what first-time buyers often don’t know is that the exposure of their home to sunlight, or how many hours of sunshine they receive, can have a direct effect on the number of solar panels they need.

Bigger is now better for rooftop solar

The number of solar panels you need for your house depends on the system size that you choose. You may, however, have a different number of panels for the same size system, depending on the brand of panels that you opt for.

Solar panels usually come in the standard dimensions of 1.70 m x 1.00 m for households, which is about 1.7m2 for each panel installed. However, for a more powerful module, the wattage output (W) of the panels would likely vary between 250W and 360W.

That explains why you will need 4 x 250W panels, or 3 x 330W for every 1kW of power your solar system needs to produce. If you are considering a 6.6kW system, that is between 18 and 20 solar panels that will depend on the brand of solar panels that you choose!

If you can manage the upfront cost and have the roof space, we suggest choosing a system size of no less than 5kW; indeed, the new sweet spot of a 6.6kW system with a 5kW inverter might be a good option.

The price of a 5kW system may vary depending on your location but expect to pay between $5,000 – $8,000 for a quality installation.

Don’t confuse kW and kWh

kW stands for “kilowatts” which is 1,000 Watts. A kW is a measure of power. The size of a solar system is defined by its peak power. e.g. a 1 kW system can produce 1 kW of power on really sunny days.

kWh, which means kilowatt-hour, is a measurement of energy (not power). So, if your solar panels continuously output 1 kW of power for an hour, then 1 kWh of energy has been generated.

We hope this article helps you get started, however, we recommend that you contact our expert solar consultations for a free customised energy saving plan for you.