Hi, I've read through different articles and answers. And I think I get the idea of calculating.
When I use a 24V battery bank and inverter who has to deliver 40W for 20hours and 200W for 4 hours that is pulling
((50*20) + (240*4))= 800+800 = 1.6 KWh on a 24h day.
With 0.85% of efficiency of the inverter that would need (1600W / 0.85) = 1882W
That on a 24V battery would then be: 1882 / 24 = 78 Amp hours.
Considering the Depth of Discharge on a lead acid battery of 50%.
78 Ah on a lead acid battery would mean I need a 156 Ah battery. (78 / 0.5)
Considering the Depth of Discharge on a lithium battery of 80%.
78 Ah on a Lithium battery would mean I need a 98 Ah battery. (78 / 0.8)
So a 98Ah battery would cover my needs for 1, 24h day.
So far so good, I think.
Considering 5 sun hours for charging the battery and the need to charge 1882 Watts.
Would that mean I need: (1882 / 5) a solar panel capacity of 376 Watts? - "Simplified"
Then taking in account losses for the Panel and the charge controller.
I think I am safe when I take 75% of capacity for the solar panels and then forget the loss in the controller.
My conclusion:
A 500 Watt Solar panel with one of the 2 batteries mentioned above would provide enough to power the inverter to deliver 1882 Watts on a daily basis.
(Not considered cloudy days or more usage then average etc etc)
Please comment
Thanks Ray.
When I use a 24V battery bank and inverter who has to deliver 40W for 20hours and 200W for 4 hours that is pulling
((50*20) + (240*4))= 800+800 = 1.6 KWh on a 24h day.
With 0.85% of efficiency of the inverter that would need (1600W / 0.85) = 1882W
That on a 24V battery would then be: 1882 / 24 = 78 Amp hours.
Considering the Depth of Discharge on a lead acid battery of 50%.
78 Ah on a lead acid battery would mean I need a 156 Ah battery. (78 / 0.5)
Considering the Depth of Discharge on a lithium battery of 80%.
78 Ah on a Lithium battery would mean I need a 98 Ah battery. (78 / 0.8)
So a 98Ah battery would cover my needs for 1, 24h day.
So far so good, I think.
Considering 5 sun hours for charging the battery and the need to charge 1882 Watts.
Would that mean I need: (1882 / 5) a solar panel capacity of 376 Watts? - "Simplified"
Then taking in account losses for the Panel and the charge controller.
I think I am safe when I take 75% of capacity for the solar panels and then forget the loss in the controller.
My conclusion:
A 500 Watt Solar panel with one of the 2 batteries mentioned above would provide enough to power the inverter to deliver 1882 Watts on a daily basis.
(Not considered cloudy days or more usage then average etc etc)
Please comment
Thanks Ray.