How Many Solar Panels Do I Need?

Our solar panel calculator makes it easy to size a solar array for your home.

  • 1 Enter Your Zip Code
  • 2 Fill Out Load Calculator
  • 2 Calculate Off-Grid System Size

Step 1: Enter Your Zip Code

Enter your zip code*, and we’ll look up the the sun hours in your area.
Error: The National Renewable Energy Laboratory?s PVWatts Calculator does not have climate data for this location. Please try another location. Or add peak sun hours per day.

*Must enter address to gather data.

How many Sun Hours a day do you average in the darkest month?

We’ll start by using your winter low sun hours to size your PV array. Keep in mind your exact needs may vary depending on how your system will be used.

Step 2: Fill Out Load Calculator

Fill out the table below to estimate energy usage. We’ve included some common household appliances found in off-grid homes. Try to account for everything, keeping in mind that off-grid homes should use efficient appliances, and the major heating loads (water & air heating) are usually not electric.

Solar Load Calculator

Appliance Quantity Power Rating (Watts) Average Daily Usage (Hours) Watt Hours per Day
Total Watts - (Peak Load)
Total Watt Hours per Hours:
Kilowatt Hours Per Day:

If you already have this total, you can enter it here.

Step 3: Calculate Off-Grid System Size

We'll estimate your off-grid system size based on the list of appliances and energy usage that you entered. Keep in mind that this is only an estimate, and there are many factors that can influence system sizing. Please contact us for help designing your project.

Click the "Calculate My System Size button" and we'll calculate your system size.
Calculate My System Size
Minimum PV
System Size


As mentioned before, this is a very basic system size estimation. It is intended to give you a general idea of what your Off-Grid solar system sizing needs would be. This system size is designed to generate the electricity needed to power the daily loads you entered into the load calculator. There are many other factors unique to your specific location and application that can effect the size off the Off-Grid solar system you need. Factors such as whether this is a seasonal property or full time, shading implications, azimuth & tilt of the solar panels, unaccounted peak load variations, available space in your main service panel (MSP), and that is just to name a few.

Here are the results of your form submission. If you would like us to email you a copy, enter your email address below.

Connect with a solar expert for a free quote

Still need help to determine how many solar panels you need for your home? We'll design and provide estimates on a solar panel system for your home. Here's how:

1. Custom Design

We use satellite technology to create solar panel layouts that fit your home’s unique specifications

2. Full technical support

Our solar kits come with step-by-step installation guides to help you set it up right the first time.

3. 100% Money back guarantee

If your permit isn’t approved even after following the proper steps, we’ll provide a full refund of your purchase.

Let us help you choose the perfect solar kit for your home!