As the RV industry continues to grow, so does the drive for renewable power. Using solar power to charge your batteries provides you the freedom to go to more out of the way places such as the beach, mountains, and many other beautiful locations that are “off the grid”. Even in the winter months, RVers are heading South to places like Quartsite, AZ where there are no hookups, several beaches such as the Padre Islands and many others. For those that like cold weather activities like cross country skiing, kite sailing and ice fishing, the RV acts as a very warm and cozy Chalet!
The 12-volt deep cycle house batteries are used to power the interior lights, vents, and run the appliances that use propane. Using an inverter can also provide 120-volt power for the TV or larger ones will run outlets for the refrigerator. So technically you can run just about everything except the roof air conditioner using the house batteries rather than being plugged into 120-volt power. However, these batteries need to be recharged either with a converter plugged into 120-volt power such as shoreline connection or generator, or alternative source such as the sun with solar panels. Using solar panels provides a quiet, convenient recharge rather than a noisy generator which sometimes can not be run in certain areas at night. It also save money and is a safe renewable energy. It provides a great back up in case of emergency when power goes out at a campground and extends battery life by reducing sulfation due to low batteries.
How Solar Charging Works
Solar charging and battery power is very similar to a fuel system in a car with the house batteries in your RV being the fuel tank. These deep cycle batteries are simply storage containers for energy that are drained and need to be refilled. They are rated in amp hours just like gallons of fuel in a fuel tank. The higher the amp hour rating, the more energy being stored and the longer you can use 12-volt systems without needing to recharge the batteries.
The solar panel provides the fuel to the batteries just like the fuel pump at a gas station. The energy or fuel is delivered through wires to a controller which is similar to a fuel station shut off valve. This prevents the solar panel from overfilling, or overcharging the batteries. With the batteries fully charged, energy is sent to the “engine” which is the distribution center or an inverter and this runs the 12-volt functions of your RV.
Solar Panel Overview
Solar panels use silicon wafers called cells to capture light from the sun and convert it to Direct Current (DC) electricity. A single panel will have several cells that will capture the sunlight and provide DC current to the controller. The controller adjusts the voltage being sent to the batteries so they can not be overcharged or boiled. Wires from the controller can go directly to the battery or batteries, or be connected to the converter or inverter if applicable. The converter is the battery charger that is either part of your distribution center as an all-in-one unit, or as a separate box which come manufacturers place under kitchen cabinetry or in the basement due to the noise of the cooling fan. An inverter is a device that will take 12-volt DC power and provide 120-volt AC power for the refrigerator and other appliances. Larger models will do a variety of appliances, however most do not have enough power for the Roof AC. This larger inverter also has a multi-stage charger to charge the batteries when connected to shoreline power or running the generator.
What Size Solar System Do You Need?
Most solar panel companies have a calculator that can help determine the size and amount of solar panels you will need. It starts with determining how much power you need to run the 12-volt systems in your rig such as lights, roof vents, water pump etc. Then identify the 120-volt appliances you will need to power through the inverter. Combine them and next determine how many hours per day you will be using them. Individual panels start as small as 30 watts and go up to 170 watts. Small trailers with one 12-volt house battery and no inverter can get by with one 80-100 watt panel for a weekend while a larger 5th wheel or motorhome with a large battery bank and inverter will need approximately two 170 watt panels for a weekend and up to 840-960 total watts for an extended trip which would require several panels.
- For a sizing chart customized to your rig, visit Go Power Solar Systems.
- You can download a sizing chart here.
So whatever your idea of winter activity is, solar power is an economical and environmentally friendly way to power your rig!
About the author: Dave Solberg: Managing Editor, RV Repair Club
For the last 25 years, Dave has conducted RV maintenance and safety seminars, developed dealer and owner training programs, written RV safety and handyman articles, authored an RV handbook reference guide and logged over 100,000 miles on the road in an RV.
RV Repair Club is your go-to online resource for enthusiasts who want quality RV maintenance, repair, and upgrade information – a community where passionate RVers can come together to gather knowledge and share their experiences.
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