By Bob Difley
In the desert, because most campsites are open to the sky, you get charging from your panels from the first glint of sun over the morning horizon until it has passed out of view in the western sky. However, since the angle of the sun is lower, you will not receive the charging power your panels are capable of unless you tilt your panels toward the sun’s trajectory across the sky – getting as close as 90 degrees to the sun as possible. Position your RV horizontal to the sun’s movement, and verify that the elevated panels – or other rooftop equipment – do not shade the silicon part of the panel.
Since winter days are shorter, your total charging time will be shorter, and your batteries may not have sufficient time to become fully recharged. Therefore, you may have to schedule more electricity-using hours (meals, showering, computer use) during daylight, so as not to deplete too much from your batteries overnight.
When you move from the desert to a pine-shaded campsite, however, your challenges change. Since the sun during the summer months passes more directly overhead, your panels do not have to be elevated to take full advantage of the sun’s rays throughout the day.
Days are longer so you have many more charging hours every day than in the desert, and since the number of nighttime dark hours roughly equals the eight hours of sleep needed, most electricity-using can be accomplished while the panels are charging if you coordinate your sleeping and rising times with the sun’s rise and set.
But now comes the hard part. Since you are camping in a forest, you will undoubtedly have periods of the day when the sun is blocked from reaching your panels by the magnificent (and tall) trees surrounding your campsite. Short of camping out in the middle of a meadow (which can be nice) you will have to guess where to park to get as many hours of sunlight as possible reaching your panels.
Try to avoid any part of the panel being shaded since that reduces the amount of amps that pass into your batteries. Then watch the sun as it moves across the sky and watch for when your panels are blocked. A small move or repositioning may gain more sunlight. Unless the surrounding trees are very tall or very close to your campsite, you should be able to get enough midday sun hours from overhead to give your system some good strong charging.
The remaining consideration in both desert and forest is the number of overcast or rainy days, which will produce reduced battery charging. It is therefore a good idea to oversize your system slightly to account for all the variables.
You can find Bob Difley’s RVing e-books on Amazon Kindle.