Powering Your Future

How Many Solar Panels Do I Need For 1,000 kWh Per Month?

May 4, 2021 8:43:36 AM / by Elise Vue

Roof solar install is becoming more affordable, efficient, and popular. One aspect that makes this form of power more attractive is power companies are being required to buy your excess power through net metering laws. This law enforces that power companies give you credit during off-hours when solar power is not available for excess power created during sunlight hours. 

Many homeowners considering a roof solar install wonder how many solar panels it would take to produce kWh a month?

How to Determine How Many Solar Panels are Needed

On average, a home in the United States uses 900 kWh each month. This number is an average as significant ranges depend on a number of factors:

  • The size of your house
  • The size of your family
  • How much energy your household consumes
  • Which state you live in

By checking your utility bill to see how much you use, and adding a cushion for times your roof solar install may not be performing at its peak, you can determine the number of solar panels you'll need. 

How Many kWh Will Solar Panels Produce Each Month?

The first thing to remember when you begin determining how many kWh solar panels will produce each month is that not all solar panels are created equal. On average a solar cell will convert about 18 percent of the sunlight that lands onto it into electricity. This percentage will vary depending on the quality of the solar panel. 

When a solar panel operates at 20 % efficiency, this will turn into about 265 watts of power an hour. The label placed on solar panels is required to list the number of kWh they will produce an hour during ideal, sunny conditions. This number is known as the STC (Standard Test Condition rating.) On average, one solar panel will create 1 kWh each day and 30 kWh each month. 

How Many kWh Can You Expect to Generate?

Most solar power company's websites have calculators for you to use to calculate the average solar panel output a day in an area. Check with Westhaven Power to determine the average output in your area. The average roof in the United States receives about four full or usable hours of sun a day. The number changes according to where you live, so four hours is an average across the country. 

To begin determining how many solar panels you will need to create 1000 kWh a month, let's begin with one roof solar install panel. If you have one solar panel at 250-watts and receive 4 hours of sunlight a day, you will receive 1 kWh a day from the one solar panel. 

This calculation means it would take thirty-three solar panels to generate 1,000 kWh a month. You will need to consider, however, that system sizes are calculated in an inverse manner or order. This means a 5 kWh system should produce a little over 7,000 kWh a year. 

Numbers vary in the calculation of determining how many panels will be needed for roof solar install, but it is good to have a preliminary calculation and then talk to the experts at Westhaven Power. 

Where to Learn More About Roof Solar Install

Westhaven Power has more than twenty years of experience in the solar power industry. We install and customize top-quality energy-efficient battery storage and solar panels. Our team is highly trained and licensed professionals ready to help design an accurate system for your home or business. 

Elise Vue

Written by Elise Vue