Solar Panels for Boat Battery Charging.

Solar Panels for Boat Battery Charging.

I have solar panels on two of my boats and they do help keep the batteries charged for the most part. Here are a few things to consider with a solar charging systems that can help you decide a system to pick.

First there are solid panels and flexible panels. Solid panels are heavier and need to be rigidly mounted so they do not slide around and break. This limits where you can mount them so they are not in the way and the placement may limit how much direct light they will get. Flexible panels let you mount them or place them in areas that are curved or even let them be movable so they can get the most light possible.

You need to be realistic on how much power you will get from them. If they are not in direct sun and facing the sun the output they produce will be way lower than what the max rating they can produce. Realistically you need to figure that the output will be 30% to 40%of the stated rating.

A PV panel that puts out less than about 10W is unlikely to require a regulator/controller. If it puts out more than 10W it should have one. BUT if you can afford a PV panel get a regulator/controller. You can get a cheap regulator for a small panel for less the $10. For a larger system get a good controller/regulator. It can prevent battery overcharging, reverse discharging, and reverse-polarity protection. It can save the batteries and the solar panels. 

If my boat sits for a number of days I know the batteries will be charged or mostly charged when am ready to use the boat. And what is nice is it is free electricity.