Figuring Out How Many Solar Panels You Need

Ashleigh AngellSeptember 24, 20183050

Figuring Out How Many Solar Panels You Need

While you may have already decided that solar energy is right for you, you might still be struggling with how exactly to implement it into your life. One of the most common questions is: How many solar panels do I actually need? First thing’s first, you’ll need to know the pertinent information about your home in order to figure out the rest: how much energy do you usually use? How large is your roof? Where is the sun’s position relative to your roof? Which panels do you want?

If all of this information is leaving you lost and confused, don’t forget that a solar panel installer can also help you and that you aren’t in the ocean without a paddle when it comes to going solar.

How much energy do you usually use?

While your first reaction to this question may be, “How should I know?” finding out the answer is actually fairly easy. Just look at your utility bills. These should give you a detailed list of exactly how much power you used and what you used it to power. From there, you should see an outline of how many kilowatts you use per hour (kWh). If your power company doesn’t provide that information, just look for the beginning and ending meter readings. Subtract the beginning reading from the very last one to find out your kWh. After you figure out your average daily use, you can look at how much energy each panel you’re interested in provides, and then use that to figure out how many panels you’ll need.

What’s the sunlight like in your area?

A good example of drastic different sunlight exposure is Phoenix versus Seattle. Phoenix has a large amount of sunlight and not a whole lot of trees to block it out, meaning you won’t have to worry about not getting enough energy from the sun. On the other hand, Seattle is cloudy most of the time, and it has a lot of trees, which would also block sunlight from your roof. This means that a homeowner in Seattle would need to buy more panels than one who lives in Phoenix.

Figure out the peak sunlight hours in your area and how much kWh you’ll need to compensate for the times the sun isn’t out, especially if you live somewhere like Seattle.

Solar Panels Aren’t Created Equal

Another thing you’ll need to consider is the quality of the panels you invest in. PV panels have wattages from 150-370 watts per panel. This means that one of lesser quality, that would only produce 150 watts, would need more panels installed on your roof than one that produces 370. Figure out the exact wattage of whichever panel you decide is right for you to make sure it’s producing enough for your lifestyle. This also means that paying more for a higher quality panel would probably be worth it because you’ll have to buy a lot less of them.

Consider Your Roof

You’ll also need to take the shape and size of your roof into consideration. For an example, if you have a large roof, you’d be able to buy more cheap ones and not worry about running out of room. But if you have a small roof, you’d probably need to buy the more expensive ones so that you’ll be producing enough energy to sustain your home.

Want more information on solar energy and implementing it into your life? Check out the HahaSmart blog!

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