When properly configured for your location and energy consumption, solar panels can power a whole house. However, in most cases, you’ll still want your local utility company to provide backup for cloudy days or extended storm fronts. If you’re intrigued by the terrific benefits of going solar, you’re smart to do some research first. Let’s further explore how solar can power your house and how you can calculate the number of solar panels for your home.
How Can Solar Panels Power a Whole House?
While it’s true that solar panels can power a whole house, you’ll note there were a couple of essential caveats. First, you will need sufficient solar panels installed to power your home. “How many solar panels do I need?” is a common question that depends upon your location and energy consumption. Although modern solar panels can continue to collect energy on cloudy days, they work at peak efficiency only when the sun is shining and unobstructed. So the same number of solar panels for a home in Seattle will convert less solar energy than those installed in a southern California desert. Of course, this means that you’ll want to install a few extra panels where cloudy weather is typical.
The other key consideration when planning solar panels for the home to power the entire house is how much energy your household consumes. For example, a couple who both work long hours away from home, with no pool to heat or air conditioning to run, will use less electricity than a family of six who all work and play from home, with a full-size heated pool, jacuzzi, and a/c. So, your energy consumption is just as important as your location when considering whether solar panels can power a whole house. If the number of solar panels is appropriately configured, you can produce all the electricity you need using your home’s solar panels.
How Many Solar Panels Do I Need?
You can calculate the number of solar panels your home needs by converting your family’s hourly energy consumption into watts, multiplying that by the number of peak sunlight hours in your location, and then dividing by the panel’s wattage. A professional solar installation company will provide this information for you. But you can find the numbers to use for this calculation pretty easily.
Your Family’s Energy Consumption by Hour
For the best information, look at 12 consecutive months of your electricity bills. Total the number of “Kilowatt Hours Used” for the twelve months. That shows you how much electricity your household used in that year. Next, divide by 365 to get the daily energy used. Then, divide by 24. You now have your home’s average hourly electricity consumption for that year.
This is the starting number for how much energy the solar panels for your home must produce to power your entire home. Multiply this number by 1,000 to convert it from kilowatts to the watts your home uses on average each hour. However, it’s wise to build in a cushion that allows for adding an electric vehicle or a jacuzzi down the road to ensure your system can grow with you.
Peak Sunlight Hours for Your Area
For math lovers, you can calculate the peak sun hours in your location with this formula: 1 peak sun hour = 1000 W/m² of sunlight per hour. However, the rest of us can turn to Google with the query “peak sunlight hours for your location.” Several free peak sun hours calculators will pop up. Enter your zip code to learn the number to use for your location. You’ll multiply this number by your family’s average hourly energy consumption in watts.
Solar Panel Wattage
Most solar panels for homes produce between 250 watts and 400 watts. If you hire a professional solar power company, they will tell you the precise wattage of their solar panels. But this average range lets you look at the answer to the all-important question, “How many solar panels do I need?”
As we've seen, the number of solar panels you need depends entirely upon where you live and your energy consumption. So, let’s see how to use our formula to determine the answer.
Suppose your family’s hourly power consumption is 1.5 kWh or kilowatts per hour. And your peak sun hours per day averages out to 5.43. And we’ll use a 300-watt solar panel for figuring. So, we’ll multiply 1.5 (hourly consumption) x 1,000 (converting to watts) x 5.43 (peak sunlight hours) = 8,145. Now, we divide by 300 (our 300-watt solar panel’s wattage) = 27.15 solar panels needed to power your entire home.
So, in this example, you would need 28 300-watt solar panels to power your home since you can’t install a fraction of a panel. If your household uses less power, you live where peak sunlight hours are greater, or your solar panels produce more watts, the number of solar panels that can power the whole house will decrease.
Where to Install Solar Panels?
The ideal placement for solar panels in the U.S. is on south-facing roofs with a slope between 15 and 40 degrees. However, rooftops facing other directions will also work well, just less efficiently. So, what happens if your roof needs to be bigger to install as many solar panels as you need? Solar panels for the home can also be installed on the ground, in parking canopies, or in pole-mount units.
Can panels power a whole house? Absolutely! And when you’re ready to move forward with this eco-friendly house renovation, call the experts. Professional solar installation companies have the experience to modify your roof without causing costly damage. Further, they’re bonded to cover potential damage.
Be sure to contact your friendly Wawanesa agent when installing solar panels to ensure your homeowner’s insurance policy covers you.
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