The duration to charge a 12V battery with 300W solar panels depends on the battery capacity and the solar panel current. For instance, at 6 peak hours and 25% system losses (efficiency is 75%), a single 300W solar panel can fully charge a 12V 50Ah battery in roughly 10 hours and 40 minutes. Let’s understand it in detail,
Now divide the battery capacity after DoD by the solar panel output (after taking into account the losses). Turns out, 100 watt solar panel will take about 9 peak sun hours to fully charge a 12v 100ah lead acid battery from 50% depth of discharge. how fast should you charge your battery?
It’s crucial to match the panel size to your 12V battery. For example, a 50Ah (600Wh) 12V battery could be adequately served by a single 150W solar panel, providing about 4-5 hours of direct sunlight a day. Suppose you have a small 5W solar panel and you aim to charge a 12V battery.
Suppose you have a small 5W solar panel and you aim to charge a 12V battery. Considering ideal conditions, it could take about 120 hours to fully charge a 50Ah battery—this emphasizes why panel size matters!
12v lead acid battery from 50% depth of discharge will take anywhere between 2 to 20 peak sun hours to get fully charged with a 100 watt solar panel. 12v lithium battery from 100% depth of discharge will take anywhere between 3 to 30 peak sun hours to get fully charged with a 100 watt solar panel.
Assume you are using a 200W solar panel and an MPPT charge controller. Solar output = 200W ×— 95% = 190W 4. Divide the discharged battery capacity by the solar output to get your estimated charge time. Charge time = 960Wh ×· 190W = 5.1 hours