When it comes to charging your battery, you need to know how many watts of power your solar charger needs to provide. Multiplying the voltage and amperage of your battery will give you the wattage you need. For example, if you have a 12V and 20A battery, you will need a 240W solar panel or three 100W solar panels. If you have a 10W solar panel exposed to sunlight for 6 hours, it will provide 60Wh of power to the battery.
Solar panel manufacturers rate their production in watts. As a rule of thumb, 15W of power will produce about 3600 coulombs (1Ah) per hour in direct sunlight. For example, the Pulse Tech SP-5 panel can emit up to 5A of current. To calculate the amount of watt-hours required, you need to calculate the amount of direct sunlight that the solar panel will receive in that time period.
Solar panels have some loss at a distance, so make sure that the solar charge controller is close to the batteries. Solar charge controllers are ideal for flooded lead-acid batteries, which are prone to overcharging. If you have a 100Ah battery, you will need a 250W solar panel if you are not using any other energy sources in your RV at the same time. To calculate the rated amperage of the solar panel, use this equation: Watts/Volts = Amps.
Solar panel mounts can be used to support solar panels on virtually any roofing system, from flat roofs to pitched roofs up to 2 in 12. You can still use solar panels without a battery, but you need a solar panel battery to store energy when the sun goes down. When it comes to choosing the right solar panels for your existing battery, or building an efficient solar energy system, it's important to consider the power requirements and amount of sunlight available. A typical 100W solar panel can produce an average of 30Ah per day (based on an average sunny day), so you will need three 100W solar panels or one 300W solar panel to fully recharge your battery.
