There is a lot to consider when it comes to installing a system of solar panels in your home. One of the most important things to consider is how large your solar system will need to be.

Everyone’s case is unique here. The size of your solar system will depend on a range of factors, from physical constraints to your personal needs and geographical location. In this article, we’ll take a look at what impacts the size of your solar system and how to calculate its size.

Factors To Work Out

The final size of your solar panel system will depend on a number of variables. Here are some of the main things you’ll need to consider:

  • The amount of electricity you need to generate per day
  • The average peak sun hours in your area
  • The efficiency of your solar panels

As an example, we can do a rough calculation for a typical house in Mackay, Queensland.

Let’s start with your electricity needs. On average, households in Queensland use 5,535kWh of energy every year. Divided by the number of days in a year (365), that gives us an average daily usage of 15.16kWh per day. This isn’t an exact figure, as daily usage varies according to the season, but it’s a good starting point.

Now let’s work out the average peak sun hours. Mackay is lucky here — the average rooftop gets 5.5 hours of peak sunlight a day (again, this varies by season).

Finally, let’s work out the efficiency of our solar panels. This is something you’ll need to confirm with your provider, but a typical range is 15-18%. Let’s assume we’re on the lower end at 15%.

Now we need to plug all the above into this equation:

(Daily energy use in kWh ÷ average peak sun hours) x efficiency factor = solar system size

So: (15.16/5.5) x 1.15 = 3.17kWh

This is pretty close to the actual Mackay average of 3.74kW. Armed with this information, you’ll be able to work out how much space you need for your solar system if it falls within your budget, and how efficient your panels will need to be.

Installing Your Panels

After working out the size your solar panel system will be, the next step is to install it. This stage should always begin with a meeting and inspection from qualified solar panel experts.

At Snap Solar, it’s our job to help you choose and set up the best possible solar system for your needs. We’ll guide you through every step of the process so you avoid any mistakes and get the most out of your panels. Get in touch with us to find out more.

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