How to Calculate the Battery Size for our Homes
Calculate the total Connected Load
| Appliances | Power | Units | Total Power |
| Fan | 60 Watt | 4 | 240 watt |
| Led Light | 20 Watt | 10 | 200 watt |
| Television | 40 Watt | 2 | 80 watt |
| Extra Load | 50 Watt | 1 | 50 watt |
Safety Factor = 25 % (we take this for the future load demand)
Overall total load = 712.50 Watt = 720 watt (approx.)
Battery Capacity is in Ampere Hour (AH)
Battery Capacity = Watt x Backup time / Battery voltage x Battery Efficiency x Inverter Eff.
= 720 watt x 3 Hour / 12 x 0.8 x 0.8
= 281.25 Ah = 300 Ah (Approx.)
Note :- The above given calculation is Rough calculation for Domestic use.
