Do you know how many solar panels you need to provide sufficient electricity for your home? Do you even know where to start to calculate this? It’s a crucial calculation if you want to ensure that you get a system that can meet your needs and avoid overpaying for a system that generates more electricity than you need.
In this post, we’ll dig a little deeper into calculating how many solar panels you need for your home.
Table of Contents
Understanding Your Power Usage
The first figure you’ll need to calculate how many solar panels you need, is your average monthly electricity usage. While the average Australian home uses between 15 and 20kWh per day, this number can vary a lot from home to home. Fortunately, it’s quite simple to calculate. You only need to look at your electricity bill for the past few months or your smart meter reading and calculate an average from that.
Solar Panel Output Options
Apart from how much electricity you use, you’ll also need to know the output of the solar panels you plan on using. Nowadays, 300 to 400-watt solar panels are becoming increasingly popular and, to find the output of yours, you can check the manufacturer’s website or get in touch with solar panel installers that install the panel.
Before installing your solar system, you’ll need to consider the orientation of the panels. Ideally, they should face north to get maximum exposure from the sun. However, this is not a requirement, as you can easily install them to face east, west, south, and everything in between. Keep in mind, though, in these cases, there might be a drop in efficiency.
Likewise, you should also consider the roof space you have available. Generally, a 5kW system takes up about 25km² and higher capacity systems require more roof area. So, based on your electricity needs, you’ll need to ensure that you have enough space available.
Calculating the Size of Your Solar Energy System
Now that you know how much electricity you need and the output of your solar panels, you can calculate the size of your solar energy system. Here, you’ll first look at how much sunlight your area gets. This is measured in peak sun hours and shows you how many kilowatt hours a 1kW solar system will generate. For example, if your area gets 150 peak sun hours a month, a 1kW solar system will generate 150kWh of electricity.
You’ll then calculate the size of your solar energy system by dividing your monthly electricity usage by the monthly peak sun hours. So, if you need 900kWh per month and your area gets 150 peak sun hours, you’ll need a 6kW system. Finally, when you know this, you can calculate how many solar panels you’ll need by first converting kilowatts to watts and then dividing by the output of the panel. As such, using the example above, you’ll need 20 panels if their output is 300w.
When you calculate the size of your solar energy system properly, you’ll ensure that you install the right system based on your unique needs and requirements. Hopefully, this post helped illustrate how you can do this. Now you only need to get in touch with a solar panel installer to get started.