There are several different power sources running the equipment that makes life in an RV more comfortable than dry camping. Let’s look at the major sources of energy used by an RV and the main alternatives within each. We’ll also discuss your options to ensure a portable power supply for camping when the default options are unavailable.
The RV Engine
The RV engine is there to move the RV. It may provide power to minor power draws like lights while the engine is running. Most RVs will let you use the RV engine to trickle charge house batteries while the engine runs, though not all do this automatically.
Another downside of running the RV engine to recharge house batteries is its low efficiency. You’re going to burn more gallons of gas running the RV engine than you would a generator designed for that purpose. A life threatening mistake is running the RV engine in an enclosed space to recharge house batteries, since you’re now creating a carbon monoxide hazard so that your water pumps and lights stay on.
In comparison, solar panels are environmentally friendly and don’t need refueling. If you make the right trade offs, you could power your life in an RV using house batteries and solar panels and only need to buy gas for your vehicle.
House batteries are the 12 volt batteries that run the basic infrastructure of the RV. These are the batteries that run the water pump, smoke detector and built-in lights. House batteries are wired into the RV itself, though it is possible to add secondary banks of house batteries. The house batteries may be recharged by running the RV motor. And they may be recharged through external sources, such as solar panels or shore power. The upside of solar power is that it is always an option, whereas you may not be able to find a campsite with shore power when you arrive in town – or all of the campsites with shore power are already booked.
When researching a portable power supply for camping, know that many of them are specifically intended to recharge house batteries. Solar panel arrays, for example, are generally used to recharge house batteries first and your smart phone second, if there’s any energy left over. You can’t rely on wind to generate enough energy to recharge house batteries, because wind power is too variable and often unavailable.
In contrast, solar panels allow you to recharge your batteries in only a few hours. The issue depends more on how large your solar panels are and their efficiency (both by design and environmental factors like shade).
The generator lets you power your TV and electrical appliances that cannot run off of the house batteries. You can use generators to recharge rechargeable batteries you use in hand tools, toys and small electronics, though you can do this with the right hardware with solar panels, too.
Generators are not all the same. Cheaper generators have poor power quality. Generators are necessary unless you’re connected to shore power if you want to power energy hogs like a portable air conditioner or microwave. Generators vary in their baseline load. You’ll pay more for a generator that can run both your air conditioner and your microwave at the same time.
The truly powerful generators capable of putting out 8000 horsepower or more are heavy and likely need to be pulled on a trailer. The downside is that this literally drags on the RV, pulling down its fuel economy.
Another matter to consider is the size of the fuel tank in the generator. The larger the fuel tank, the longer it will generally be able to run. A more powerful generator plus larger gas tank may require mounting the generator on the roof of the RV, affecting what routes you can take, or loading it onto the back of the RV and hoping it isn’t stolen. Or you have to give up storage space inside the RV to make room for it. Solar panels mounted on the roof without taking up storage space or much extra weight is starting to look quite attractive.
There’s another differentiating factor between generators, and that is regarding fuel sources. Most generators run off of gasoline. This has the clear benefit of letting you use the same gas that powers the RV to power everything else inside it, too. You could top off the gas generator fuel tank as you fill up the RV gas tank, and if the generator tank goes dry, you can pull gas from the gas tank to run it.
Some generators use propane instead. If you have a gas grill in the RV or propane powered refrigerator, you’re probably already going to be in the habit of stocking up on propane tanks. One point in favor of propane generators is that they’re far less toxic than gas generators, though solar panels have no such potential ill effects.
It is almost impossible to spill propane, and if you did, it evaporates immediately. Propane generators are quieter than gas generators. Propane costs half as much as gas. It burns cleaner, so there is less risk of carbon monoxide poisoning. Conversely, solar panels will never hurt the environment or the owner.
The biggest downside of propane generators is the relative scarcity of propane suppliers. You can find gas stations at nearly every crossroads even in rural areas; not all of these have propane tanks, and those that do may only have the propane tanks RV generator would need. Conversely, a benefit of propane is that it will still be available when there is a power outage. If the power goes out, you can’t get most gas station pumps to work. Gasoline can only be stored for up to a year in most situations, while propane can be stored indefinitely.
However, a propane generator is almost useless when temperatures are below 20. Propane generators are more complicated than gas generators, so they’re prone to failing – and they will struggle to run when temperatures are below freezing. There are flex-fuel generators that can run off both propane and gas, but they cost significantly more than gas generators.
Let’s compare this to solar panels. Solar panels are equally efficient in warm temperatures as in low temperatures, though there is the possibility that your chores include scraping snow or sand off the solar panels. You’ll never need to top off your fuel if you have solar panels to recharge your batteries. There’s no risk of toxic chemical exposure when you’re using solar panels. The panels can be cleaned with water or cleaners specifically for that purpose.
You can simply set up the solar panel array and leave it up as it charges your house batteries and anything else connected to it. There’s no need to monitor fuel levels and refill gas tanks. You don’t need to clean fuel filters or rinse out gas tanks of sediment. If the solar panels are mounted on the top of the RV and wired into your RV’s electrical system, there’s not even set-up and tear down to take into account in your schedule. Because there are no moving parts in solar panel arrays, you never have to worry about getting a generator fixed on short notice to keep your lights on.
There are solar panel control systems that can accept power coming in from multiple solar panels and route it where needed. The smart ones will ensure that your smart phone is actually charging and won’t overcharge your house batteries. The alternative is connecting an inverter that stores some of the power coming in from the solar panels and ensuring that smart devices are both fully charged and receive high quality power.
Shore power is the term that refers to your connection to the local power grid when parked in a campsite with utilities. You’d also call it shore power if you run an extension cord from your friend’s outdoor power outlet to your RV. One benefit of using shore power is that you don’t have to refuel a generator or drain down house batteries while running your appliances.
The downside is that the shore power can only run appliances and devices that use alternating current. You can probably buy an inverter that lets you turn shore power into direct current safe to use to recharge your house batteries.
The biggest advantage of using solar power is that you can power life in an RV for weeks without ever having access to shore power. You can find roll up solar arrays that are an ideal portable power supply for camping, since you can take them with you while backpacking to an even more remote site. Or you can take smaller solar panel arrays to spots you’d like to picnic or work as amateur radio operators. You can power small electronics like a GPS or digital camera, as long as you’re careful to conserve your power.
There are a variety of options for powering life in an RV. The RV engine, house batteries and external power source connections are the default. Generators supplement all of the above, regardless of their fuel source. However, portable additional power sources like flexible solar cells or permanently mounted PV cells are superior in their versatility and reliability.