Solar has become increasingly attractive recently due to its financial and environmental benefits. A common question homeowners ask is, “Can solar panels power a whole house?” Homeowners want to know if it’s a good idea to switch to solar and see if they can drastically reduce their energy costs or eliminate their utility bills and no longer depend on grid electricity. The answer is – yes, solar panels can power a whole house! Yet, many factors go into whether it makes sense to do so. Read on to learn if you can power a whole house with solar panels.
What factors are important in determining whether solar panels can power your entire house?
The most important thing to take note of before figuring out if you can power your house with solar panels is if you’ll be able to pair energy storage with your solar panel system. If you don’t have a solar-plus-storage system you won’t be able to store your solar power for later use. Without a solar battery, homeowners are only able to use solar electricity as it is being produced during the day. The excess energy a system produces will be sent back to the grid and may be lost forever. Without solar battery storage, you will be forced to pull electricity from your utility company at night as solar panels can only generate electricity during sunlight hours.
There are a few things you’ll need to consider in determining whether solar panels can power your entire house, including the wattage of the solar panels you’ll install, the number of hours of sunlight your house receives each day, the type of solar panels you’ll be installing, and your annual energy consumption rate.
How many solar panels are needed to power your whole home?
The average home would need 15 to 25 solar panels to power an entire house. To find out how many you would need to power your home gather the following information: how many hours of daily sunlight your home receives, the solar power rating of the panels you’re considering, and how much energy you consume hourly.
When it comes to determining how many hours of sunlight your home receives in a day, the answer varies, and sometimes widely, between regions. For example, Arizona has the highest number of sunniest days out of any state in the nation. A homeowner there would expect to see much more sunlight than in a state like Washington, which has the highest number of cloudy days in the country. You’ll need to find out the number of daily peak sunlight hours for your area, which can be found with the National Renewable Energy Laboratory’s U.S. Annual Solar Global Horizon Irradiance map.
For example, let’s say you live in Southern Arizona. The map shows you see about 5.75 daily peak sunlight hours.
Now figure out your daily energy consumption rate. This number can change from year to year and month to month so this figure will be an estimate. You can find your daily energy usage by finding your most recent energy bill and locating the total amount of electricity you used for the month. The figure should be in kilowatt-hours (kWh). Since your electricity usage varies month to month and the total kWh usage between each electricity bill can vary widely, it is best to grab every energy bill you received for the year. Then, add up the total usage numbers and divide that sum by twelve.
If you don’t have your old power bills, you may be able to access them online or speak to your utility company on the phone. If you can’t access them, do what you can with the energy bills you do have. From there figure out your daily usage by dividing the monthly usage number by 30.4 (the average amount of days in a month) for the total energy consumption for each day.
For example, let’s say your household consumes an average of 850 kWh of electricity per month.
850 kWh/30.4 = 27.96 kWh per day
Once you know how much energy your solar array needs to produce every day, you’ll need to figure out what the solar panel power ratings (solar panel wattage) of the system you’re considering are. Typical home solar panels are rated for 250 to 400 watts. This rating translates to how many watts (W) of electricity your panels should produce per hour. You’ll need to convert that to kW to match it with the previous calculations.
1,000 W equals 1 kW, so the average would be .25 kW – 0.40 kW.
For our example, we’ll say the solar panels are rated for 320 kW, which equals 0.32 kW.
Now, the final step. Take your home’s daily power requirement in kWh and divide it by your solar panels’ power rating in kW X the daily peak sunlight hours.
27.96 kWh / (0.32kW X 5.75) = 15.19. So you’ll need about 15 panels to power your home.
What happens to excess power from a solar panel?
If a solar power system produces more energy than the home consumes, you can bank that excess electricity in a battery storage system to use as backup power in the event of a power outage or whenever you want to use it. Most home solar companies, like WattLogic, offer solar solutions and solar installation that come paired with energy storage. With new battery storage technology and increased demand on utility companies, battery storage is a popular choice for homeowners looking to maximize their independence and regain control of their main energy source through battery backup.
If you decide to forgo an energy storage system, you may be eligible for net energy metering (NEM) programs. With NEM, a homeowner receives credits from their power company for the excess electricity their solar energy system generates and sends back to the grid.
How do I maximize solar energy for my home?
With careful planning and the right solar company, you can certainly power your home with solar panels. This article may not be enough for you to start an entire “off-grid” solar system on your own, but with help from a trusted solar company and the correct solar installation, you can have the home solar system that you envision. You may not want to power your whole house with solar and that’s fine, too! No matter how many solar panels you have you’ll be generating an energy source that is good for your wallet and the planet.
WattLogic can help you understand exactly how many solar panels you would need to power your whole house or what you would need if you want a smaller solar array with fewer panels to lower your energy bills. We strive to offer the best solar panel installation to fit your energy needs. Connect with a WattLogic residential solar expert on your time for a quick 15-minute chat.