The amount of solar energy that is available for your RV solar panels to harness depends on a number of factors - whether it's full sunshine out there, if your RV is parked on a shady spot, among others. Still, the voltage output of your solar panels should be just right for your needs. You'll need to be able to regulate this voltage output using a solar charge controller.
A solar charge controller will do two things for your RV solar panel system. One, it helps you ensure that your solar panels will produce enough power for your needs. Two, it prevents your solar panels from leeching power from your batteries at night when there is no sunlight
You can't buy just any solar charge controller, though. For one, you have to ensure that its amp rating is 25% higher than the amp peak power of your RV solar panel equipment. This will ensure that you'll have enough power for your daily energy consumption without wasting a lot of the harvested solar energy.
Another point you have to consider when purchasing a solar charge controller is how it will work with your batteries. It is recommended that you get a solar charge controller that has:
Multistage charging and pulse width modulation. This will allow your RV batteries to charge in phases. Charging in phases in turn lets your batteries power up faster and more completely as well as prevents them from overcharging.
Adjustable voltage set point. A solar charge controller with this feature will allow you to adjust the charge voltage to the type of batteries you have in your RV - whether it's AGM, flooded lead acid, or gel.
Battery temperature compensation. Your batteries' charging is largely affected by temperature. If it's too hot, your batteries may overcharge. If it's too cold, your batteries may not charge up to full capacity. If your solar charge controller can compensate for battery temperature, it will automatically adjust charging based on your batteries' temperature.
Maximum power point tracking. Sometimes, when your battery voltage is low and your solar panels are cool, you'll need to boost your batteries' charging or speed up the process. A solar charge controller with maximum power point tracking will help you do that.
You'll also need to ensure that your solar charge controller has an on/off switch as well as a dry camping switch. An on/off switch will allow you to stop charging your RV batteries with energy from the solar panel without disconnecting the two. The dry camping switch, on the other hand, will let you hook up your RV back to the regular power grid. It will also let you charge your batteries as part of their maintenance when you take your RV into and out of storage.
Other Ways to Maximize Your RV Solar Panels Efficiency
There are other ways to improve the efficiency of your RV solar panels. One is to install your solar panels on L-bars so you can tilt them to the south when necessary. Tilting them to the south will get your solar panels harvesting as much sunlight as possible. This especially helps in winter when the sun is lower to the south in the sky.
Installing your solar panels on L-bars will also allow you to take your location into consideration when harvesting sunlight. As mentioned earlier, the further north you go, the less sunlight your solar panels will get. By tilting your solar panels at a certain angle to the south, you'll ensure that your panels will receive as much sunlight as possible. To calculate the angle by which you should tilt your solar panels, you should get the latitude of your location, multiply the latitude by 0.89, and then add 24 degrees to the resulting figure. You can easily Google your location's latitude.
Additionally, you will be able to protect your solar panels from costly wind damage if you fit them on L-bars. When the wind is too strong, you can lay your solar panels flat against your RV's roof.
Another way you can increase the efficiency of your RV solar panels is by giving thought to the layout of your RV's interior before you put up your solar panels. When you have a solar panel on your RV, you will need to park your rig so that your solar panel tilts to the south. So you won't waste your harnessed solar energy, it will help a lot if your appliances are situated on the cooler side of your RV (the side facing north) where they won't get a lot of heat from direct sunlight.
You really should consider powering your RV using solar energy. There are so many advantages including saving time and money. You will also get that good, fuzzy feeling that comes from knowing you have done your part in saving the environment.