How Much Solar Panel To Charge Battery

Environmental factors will likely increase charge time.

How much solar panel to charge battery.

So if you have a 100ah rv battery you can charge 50 of it in a little over 8 hours 50ah 6a 8 33. 50 is 50 of our 100ah battery and 6 is how many amps the 100w solar panel is generating. So if you have a solar panel that with a 10 watts power rating and it is exposed to sunlight for at least 6 hours. This panel will generate more power which will make a battery recharge faster.

Now we have also assumed that there are 6 peak sunlight hours. Generally a fully discharged 12 volt 100ah battery needs 1200 watts of energy to be 100 recharged. For example if your solar panel is 300w and you want to charge a 12v battery you d divide 300 by 12 to get 25 amps. It is essentially the rule of the thumb for this procedure.

3 choose an mppt charge controller for better efficiency. Since we assumed that battery is at 10 level it means that we have to charge 2400whr 90 2160whr the energy we need from solar panels is 2 16kwhr. A 100w solar panel like the renogy 100w i own two of these generates about 6 amps per hour 50 70 watts during the peak sun hours of the day. Some quick rules for estimation.

The solar charge times above assume a 25 degree celsius day with the panel pointed directly at the sun. There are two main types of controllers in the market which include on off and pulse width module pwm. Another suggestion is to match your battery capacity in amp hours with your solar output in watts. In that case you d get a charge controller rated for 30 amps.

When charging batteries with solar energy one should use a controller when the rated amperage of the solar panel is above 1 of the battery capacity. You can get the amount of energy it will provide the battery by multiplying 10 watts by 6 hours which will give you 60 wh. 10 watt 18 volt solar panel charging a 12v 10 amp hour lead acid battery 120 wh from 50 full to full time 60wh x 2 10 watts 12 hours. If you re concerned about performance and speed invest in a 16 volt solar panel instead.

This means that on that scenario the solar panel delivered 60 watts of power to charge the battery. In order to charge a 12 volt battery efficiently you ll need a solar panel that produces 12 volts. So in order to charge these batteries in 6 hours we should have 2160whr 6hr 360w solar panels.