# How to calculate Solar Battery Backup Time ?

Energy is something which plays a really important role in our individual's life. Living things and Non-living things both require some kind of energy to live, perform or react. We human get energy from food, oxygen, and water whereas in non-living things it stores some charges from different mediums like sun, air, etc. which is also a form of Energy which generally human uses for their own purpose. Selenium and germanium are some of their best examples.

Solar Energy is kind of blessings for the human life. This is free, Maintance free and long living source of energy. In this blog, we are going to see how to charge a battery from the Power of the sun and how to calculate the backup time of the Battery. So let's get started.

There are three components which are major in solar power systems, Solar panels, Inverter, and battery. battery is the main key of any off-grid solar system. Battery only decides how much backup it will give.

Battery capacity is measured in the form of AH (ampere-hour), Generally, people use 12v of battery and provides 80% of efficiency.

Battery Back Time :

Formula: Battery AH * 12V * efficiency of battery / Power Consumption in watts.

Example: We are running 2 fans with 75w then it will consume 150w then as per the calculation.

Backup Time: (100ah * 12v *0.8 efficiency) / 150watt = 6.4 hours

This will provide you the backup of 6.4 hours of backup.

The total amount of energy stored in a battery can be calculated as: Battery Size * Battery Voltage.

For example, if you have a battery of 35 ah 12V then it can store up to 420 WH. If the charging solar panel of 50 watts, then It can take (420/50) 8.4 hours to fully charge from zero to full. In this way, the battery can run 50 watts of load for 8.4 hours.

I hope this blog will help you to understand the battery backup time of a Battery. We can use this concept in Solar Power.

Happy Hacking :)