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How Many Solar Panels Do You Need?

Updated: Dec 2, 2022

If you’re considering a solar energy system, determining the number of solar panels you’ll need is based on a number of factors, including the following:

· What are your energy requirements?

· How many kilowatt hours do you currently use each month? (This number is usually on your utility bill)

· What type of solar panels are you considering?

· What is the size of your roof?

· What is the climate and the average amount of sunlight you get?

Most people purchase solar energy systems to save money on their electric bill. You’ll need to calculate your average daily energy use, which will determine how many kilowatt hours your solar energy system should produce in order for you to cover most, or all, of your electricity needs each month.

The type of solar panels also makes a difference. Solar panels have broad variations in quality and efficiency, and the more efficient the panel (e.g the more wattages it produces), the fewer panels you’ll need. Photovoltaic (PV) solar panels are most commonly used on homes, and wattages range from approximately 150 watts to 370 watts per panel. Moreover, solar cells with no grid lines on the front absorb more sunlight and are more efficient. SunPower Maxeon® cells, for instance, absorb more sunlight than conventional cells and are more resistant to cracking or corrosion than conventional cells.

If you live in a sunny climate, your solar energy system will produce more energy and you’ll need fewer panels than if you live in an area with a low level of peak sunlight hours. If your roof has limited area for solar panels or is partially shaded, you might consider fewer, smaller, but high-efficiency panels. Typically, solar panels measure about 65 inches by 39 inches, although SunPower panels are 61.3 inches by 41.2 inches and weigh just 33 pounds.

Your best bet is to contact an iSP expert, who can provide you with a free home solar evaluation and recommend the best solution for your needs.


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