If you’ve been looking for a greener energy option, you’ve probably started considering adding solar energy power to your house.
You might worry about having to cover your roof in panels or buying more panels than you need. Being a smart solar customer means understanding the factors needed in figuring out the best solar configuration for your house.
So how many panels do you need to power your house? How many are needed to offset all of your energy use? Let’s take a look at how to calculate the optimal number for your home.
Information You Need
Unlike when you install an HVAC system, there’s a lot more than just the size of your house that goes into figuring out how many panels you need. The average solar powered home needs at least 20 panels to cover 100 percent of its energy needs, but there are a lot of factors that go into the calculation to reach that number.
A solar professional can assess your home to help you figure out the right number and placement based on these factors:
- How much electricity you use on average in a year
- Amount of usable roof space you have and pitch of the roof
- Amount of sun you get
- Type of equipment such as panel wattage and power optimizers
Most energy providers have a way for you to see your annual consumption easily through their online systems. If you don’t see it in yours, you can get a good estimate by pulling some bills from the past 12 months. Get an average of the kWh amounts listed on the bills, then multiply the average by 12 to get an estimate of annual consumption.
The average household uses around 10,650 kWh per year, which should give you an idea of where your numbers should fall.
The amount of sun you get on your house plays a big role in how much solar power energy can be produced. How much shade your house gets and which direction the panels will face are key variables to take into consideration, as well as the time of year.
One other number you can track down is how much sun you’ll get based on your location. Your state’s production ratio can run from 1 in states like Maine to 1.8 in states like Arizona.
How Many Solar Panels You Will Need
A home of about 1,500 square feet with an electric bill of $100 per month would need 16-to-20 panels to cover its power needs. Now that you have the numbers for energy consumption and your state’s solar production ratio, you can figure out the specific number of panels you need for your situation.
To figure out the smart solar power configuration for your house, you divide your energy consumption by the solar production ratio. That number is then divided by the wattage of the panels you plan to buy.
- 11,000 kWh per year, divided by a production ratio of 1.5 = 9,565
- 9,565 divided by a 250-watt panel = 38.26 panels required
You can tweak the numbers by increasing the panel wattage. Upping it to 330 watts in the calculation above changes your needs to 29 panels. The cost of the panels and the amount of roof space can dictate the right wattage for your setup.
Be a Smart Solar Shopper
Adding solar power to your home is a great investment that can save you money and improve your home’s value. Smart solar shoppers know how to calculate the numbers that determine the correct number of panels to get enough solar energy to run a house.
Learn more about projects to improve your home and save money with our articles on home, money, and lifestyle topics.