For the sake of example if you are getting 5 hours of direct sunlight per day in a sunny state like california you can calculate your solar panel output this way.
Solar panel amp hours.
Thus the output for each solar panel in your array would.
How much energy does a solar panel produce.
For example 24 kwh 500 amp hours at 48 volts 500 ah x 48v 24 kwh it s usually a good idea to round up to help cover inverter inefficiencies voltage drop and other losses.
But the nrel website goes beyond that.
You can expect your panel to produce roughly this amount per day in the spring and fall.
This map shows watt hours per 100 watts of solar panel system capacity.
Then take the battery capacity which measured in ah and divide it by the amp rating the result from prior computation of the solar panel and then adding 10 of the charging time.
Note that these figures show average output.
It also assumes a perfect installation facing due south at an optimal tilt angle and unshaded between 9am and 3pm.
One 100 watt solar panel in 10 hours of strong sunlight every day into your battery and you are self sufficient.
Solar panel efficiency solar panels are rated for their max efficiency that is a 100 watt solar panel will produce 100 watts in perfect conditions.
In a perfect world that you use 1 kwh per day.
Recharging at a rate of 7 amps a day while the draw amount is 70 amps a day is not going to be enough.
A solar panel will generate electricity when placed in the sun.
Current will flow from a panel connected to an electrical circuit.
How many amps of electricity the panel will produce depends on.
For 3 days that s 210 amps total draw.
To clarify some of the mystique involving watts amps and amp hours let s begin with a 100 watt solar panel that produces 5 amps during peak sun hours a solar day.
1203 watt hours 12 volts 100 amp hours per day.
In the real world never drag your batteries below 50 charge.
Which is remarkably close to the 30 amp hour per day rule of thumb.
First you will have to determine the ampere per hour rating of the solar panel by dividing its power generation rating given in watts by the voltage of the battery.
Amp hours are based on 6 hrs.
For 6 hours that s 70 amps.
Usable sunlight per day.
A 130 amp hour battery will not cut it especially considering an 18 watt solar panel will only charge at a rate of 1 25 amps per hour.
100 amp hours per day 3 panels 33 amp hours per day per panel.
To get that kilowatt hour back in your batteries your panels have to put in 100 amp hours from the sun before it sets.
5 hours x 290 watts an example wattage of a premium solar panel 1 450 watts hours or roughly 1 5 kilowatt hours kwh.