877-878-4060

Off Grid Solar System Sizing Calculator

The altE Off Grid Solar System Sizing Calculator helps you correctly size the battery bank, Watts of solar power, and charge controller you will need for an off grid solar panel system in your location. This calculator makes sizing recommendations based on the average amount of sunlight received during the least sunny month of the year for your location. For more security and peace of mind, you may want to consider sizing your system a bit larger than the calculator suggests - or adding a backup generator. Feel free to call our knowledgeable technical sales staff toll-free at 877-878-4060 for help sizing a system that fits your needs.

Battery Bank Sizing Calculator

Let's determine the size of the battery bank for your system.

Step 1

For Watt-Hours/Day, please use our kWh Calculator. For Monthly kWh, check your monthly kilowatt-hour usage printed on your electric bills.
1 kWh = 1000 Wh

Step 2

How many days of backup power do you want in case of cloudy/rainy days (when your solar panels will produce little energy)?

Step 3

What is the lowest temperature your battery bank will experience?

Step 4

Battery Bank Capacity

Please enter your Energy Usage to get started

Solar Panel Array Sizing Calculator

This calculator helps you size the solar panel array needed for your system.

Step 5

OR
If you know this value, you can enter it directly or enter your zip code to automatically determine this value.

Solar Array Size

Please enter your Energy Usage and Zip Code to get started

Charge Controller Sizing Calculator

This calculator helps you size the charge controller(s) needed for your system.

Step 6

How many solar panels do you need? That depends on the panel you choose. Select the wattage of the panel you're interested in and we'll give you an estimate.

Charge Controller Size

Please enter your Energy Usage and Zip Code to get started

Get a Quote!

Now that you have sized up a system that fits your needs, it's time to get started with technical input on your design by submitting a formal request!

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