When you plan to install a solar system at your home, you should know how much electricity you use in your home, which will, in turn, show you the size of the system you need. Based on this, you’ll know how many solar panels you need for your home. It’s the only way you can avoid spending too much on a system that’s too large or installing a system that’s insufficient.
In this post, we’ll show you how to do these calculations.
Understanding Your Power Usage
The first step in calculating how many solar panels you need for your home is understanding your home’s electricity usage. This lays the foundation for the remainder of the calculations. But now the question is: How do you calculate your power usage? It’s actually quite simple and you only need to look at your electricity bill or smart meter readings for the past few months. From these, you’ll then calculate an average.
Solar Panel Output Options
The next figure you’ll need to calculate how many solar panels you need for your home is the panel’s output. About ten years ago, most homes used 100-watt panels while, nowadays, 300 to 400-watt panels are becoming more popular. You’ll find the output for the specific panel from either the manufacturer or the installer and, the higher the output, the fewer panels you’ll need to meet your needs.
Installation Considerations
Before installing your system, there are some things you’ll need to consider. For one, you’ll need to consider the roof space you have available. This will give you an idea of how many panels you can fit on your roof and, if need be, install higher output panels to save space.
Another consideration is the panels’ orientation. Ideally, you’ll want your panels to face north. While this gives them the maximum sun exposure, it’s not a hard-and-fast requirement. This means you can install your panels to face east, west, south, and everything in between, even though they might be less efficient.
Calculating the Size of Your Solar Energy System
Let’s now look at how you would calculate the size of your solar system. Here, you’ll follow these steps:
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Your electricity needs. We’ve already mentioned this aspect earlier and showed you how you can calculate the average monthly electricity requirement for you and your family.
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Peak sunshine hours. Once you know how much electricity you’ll need, you also need to know how many sunlight hours your area gets. This is typically measured as peak sun hours and shows you how much electricity a 1kW solar system will produce. For instance, if your area gets 150 peak sun hours a month, a 1kW solar system will generate 150kWh of electricity.
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Calculate. You can now calculate the size of the system you’ll need. To do this, you’ll divide your electricity requirement by the number of peak sun hours. So, if you use 900kWh of electricity per month and your area gets 150 peak sun hours, you’ll need a 6kW system. Based on this, you can calculate the number of solar panels you need by first converting kilowatts to watts and then dividing by the output of the panels. So, for a 6kW system, you’ll need 20 panels if they have an output of 300w.
Conclusion
There you go, now you know how to calculate how many solar panels you’ll need to provide enough electricity to meet the needs of you and your family. The only thing you need to do now is to get in touch with a qualified solar installer to get started with your installation.
