RV solar panels: What you need to know

Love your RV, but don’t want to rely on electrical hookups or a loud, smelly generator? Whether you’re a full-timer or just looking forward to a weekend off the grid, solar power can provide free, clean energy for your RV—wherever you can find a sunny spot to park it.

There are two main ways to go solar in your RV: You can invest in permanent, roof-mounted panels that are hardwired to your RV’s battery bank. Or you could opt for portable solar panels that you set up and break down at each campsite. The right choice depends on your budget, energy needs, and a few other factors.

Most RVs have two electrical systems that power different sets of equipment and appliances. Anything that you plug into a standard wall outlet, as well as power-hungry appliances like your air conditioner, run on an alternating current (AC) system, a lot like a typical household electrical system. Devices on the AC system work when you’re plugged into an external power source, like an electrical hookup at a campsite (known as shore power) or a generator.

Your lights, fans, water pumps, and other essential electronics run on the direct current (DC) system, powered by your RV’s house battery. In most cases, your battery bank charges when your engine is running or you’re hooked up to an external power source.

When you’re connected to shore power, you can run all electrical devices on both systems. But if you’d like to boondock (also called dry camping) and explore places beyond typical RV fee campsites, then you’ll be dependent on the power you can generate and store in your battery pack. That’s where solar comes in.

This is the set it and forget it method for powering your RV off grid, and a great option if you’re willing to invest a bit more up front to enjoy incredibly low-maintenance, free energy down the road. 

By mounting photovoltaic solar panels on the roof of your RV and connecting them via a charge controller to your battery bank, you can charge your RV’s battery whenever you’re driving or parked in a sunny location. You can draw on this free energy stored in your battery pack to power anything on your DC system, which generally includes the essentials if you’re happy with a more minimal boondocking experience. 

Most people who invest in mounting and hardwiring solar panels, however, will add an inverter to the system so that their battery can power the AC electrical system as well. This is certainly the more comfortable option as the AC system is generally what allows you to charge your devices, turn on a TV, or brew a pot of coffee.

This will vary based on how much electricity you use in a day and to some degree on how much solar exposure you can expect where you camp. 

Start by estimating your usage: How much power do your various appliances and systems draw in a day? This website offers a sample usage estimate as well as fillable spreadsheets and guidance to help you calculate your own. As a general starting point, experienced boondockers recommend at least a 200-watt system to cover the essentials. For comfort-minded RVers, 400-700 watts seems to be the sweet spot.

Air conditioning is the difference-maker

Depending on the size of your air conditioner, running it for 12 hours will use between 8,400 and 15,600 watt-hours. That’s a major power drain, and you’d need at least a 1400-watt solar system and a seriously upgraded battery pack just to power an air conditioner at the lowest end of that range. While it’s not impossible to size an RV solar system to accommodate long hours running the air conditioning, you’ll need considerable roof space for additional panels and bay space for additional batteries. 

More pragmatic RVers might consider sizing their solar setups for temperate boondocking, and plan to access shore power on the hottest nights.

The total cost of your system will include solar panels as well as a charge controller, inverter, wiring, and professional installation if you’re not experienced with electrical work. There’s a good chance you’ll need to add additional battery capacity as well. Battery capacity is measured in Amp hours (Ah), and a good rule of thumb is to aim for 100 usable Amp hours per every 200 watts of solar. The component costs for a 400-watt, 200 usable Ah system start just above $2,000 dollars. Expect to pay more for a professionally installed system and less if you plan to use your existing battery pack.

A hassle-free, permanent solar RV set-up is a great option for full-timers and regular boondockers who will quickly make back their up-front investment through energy savings. If you only occasionally stray beyond campsites that charge flat-rate fees for access to shore power, then it will take you longer to realize energy savings and it might make more sense to get a portable solar setup.

Portable solar is a great option if you’re looking to save on the cost of installation, while still capturing enough free solar energy to power your RV’s essentials. While portable solar panels aren’t as efficient as the panels you’d mount to your RV’s roof, they can still be a good option for more minimalist boondockers and especially those operating smaller coaches, trailers, or campervans.

As we cover in more detail in another guide, portable solar panels are lightweight, foldable panels that offer a convenient, low-cost solution for powering RVs off grid. Popular manufacturers like Renogy sell 200-watt kits with everything you need to hook up to your RV battery for $469.99. They’re easy to use, too: You’ll just set up portable panels in a sunny spot and connect them to a charge controller and your RV house battery via alligator clips.

The major downside to portable solar is the convenience you give up compared to permanent, roof-mounted panels; you’ll need to set them up and break them down each time you camp. Portable solar is also more vulnerable to theft than bolted-on panels.

But portability has other upsides apart from the lower price. With portable solar, you can set up your panels in a sunny spot and park your rig in nearby shade. It’s also easy to move between powering your RV one week and other small, off-grid systems like a boat or a shed the next. 

As an RV owner, you can save money by installing an RV solar panel system, but you'll reap more savings when you install a ground-mounted or rooftop system on your permanent property. To better understand your options for installation, check out EnergySage's Marketplace, where you can register your property and receive multiple solar quotes from local, pre-screened solar installers.