MUST KNOW Off-Grid Solar Sizing Equations: Calculate EXACT Run Times -
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MUST KNOW Solar Sizing Equations: Learn How to Calculate EXACT Battery Bank Recharge Time & Run Time

MUST KNOW Solar Generator Equations Learn How to Calculate EXACT Solar Generator Recharge Time & Run Time

Short on Time? Here’s The Article Summary

The article discusses the important factors to consider when determining the lifespan and charging time of a solar generator or battery bank. It introduces two key equations for solar sizing: the battery recharge rate and the battery bank usage time. These equations help in understanding how long it will take to recharge a solar generator from the sun and how long it will last under specific loads.

The article emphasizes the relevance of these calculations for off-grid living and solar setups of various sizes. It also mentions a solar calculator for estimating power needs based on household appliances. The article encourages readers to explore additional resources on solar generators and related topics.


Wondering how long a solar generator / solar battery will last in hours? Or how long it will take to charge a solar generator / solar battery bank from solar panels?

The video below explains the two most important solar sizing equations you need to know when shopping for ANY solar generator / off-grid (battery based) solar kit. Once you understand these two solar sizing equations, you will know how to choose the best solar generator for your needs.

The 2 most common off-grid solar questions we get asked are:

#1. How long will it take to recharge this solar generator from the sun?

#2. How long will this solar generator last me?

The video explains the exact calculations you need to know in order to figure out the answers to the two questions above. (Keep in mind the same logic applies to bigger off-grid battery banks as well).

 Again, to recap the video, these two off-grid solar sizing equations are:

#1. Battery Recharge Rate (From Panels or Outlet) = Battery size in watt hours / Total wattage input 

#2. Battery Bank Usage Time or "Run Time" = Battery size in watt hours / Load size in watts


Looking for more information on solar generators? Read our most in-depth solar generator buyer's guide ever written!

Below you will find a link to the solar calculator discussed at the end of the video. You can go check out the most common household appliances and the average watt hour draw to figure out which generator makes the most sense for you. -- watt hour calculator

Did you find this blog helpful? then consider checking others:

How Long Does It Take to Charge a 12V Battery with a 100W Solar Panel? and How to Charge a Deep Cycle Battery?

Still have questions? Don't hesitate to reach out or give us a call today at 877-242-2792

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Previous article Solar Powered Generators: 2 Most Common Questions We Get, Answered [Generator Sizing Guide]


Tallman Whitler - February 28, 2024

How big of a battery backup would I need for a house that uses about 47kwh per day?

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