There are many benefits of having solar on your RV but there are also reasons why you should NOT install solar. This article will help you figure out whether an onboard solar system will benefit you and your style of RVing. I’ll also layout the components of an RV solar system, what they do, and how much they cost.
If you have unanswered questions about solar for your RV like “Is solar worth the investment?” or “How much does an RV solar system cost?”, then hopefully you’ll leave here with an answer.
My wife and I have enjoyed RVing with solar and being off-the-grid for many years now, but our priorities and reasons for doing so may not be the same as yours. Take your time and learn as much as possible to really understand your options. That way you’ll have realistic expectations and know that your money is well spent on a system best suited to your needs.
Will You Benefit From Solar?
The only time you will benefit from solar is when your RV is disconnected from shore power. There is no reason to have solar on your RV if you primarily stay in full-hookup RV parks.
If you enjoy boondocking for days at a time in sunny locations (like the Southwest), a permanently installed RV solar system could provide the energy independence you’re looking for.
If occaisional boondocking is your thing, then a portable solar panel kit may be all you need to benefit from solar and avoid a potentially costly permanent installation.
How Solar Changed our RV Life
Having the ability to travel and camp off-the-grid in our RV has totally changed how we RV for the better. Electrical power is now a renewable resource. There’s very little to do with solar except monitor the system.
Having electrical independence is awesome! Solar has greatly enhanced our RVing experience and expanded our camping options. We’ve transitioned from campsites with hookups to ANY campsite.
Being off-grid and fully powered adds a level of freedom we’ve never experienced before. It simply feels natural now.
I’ve documented our entire off-grid solar system in this article with diagrams and explanations if you’re interested in learning more about our setup.
Solar is for Battery Charging
A common misconception is that solar panels will power your RV. While this is not entirely false, it is a mistake to think of solar panels in that capacity. The primary purpose for solar panels on an RV is to recharge your battery bank when not connected to shore power or powered by generator.
Solar power is only one of three ways to recharge your RV’s house batteries. Your RV on-board or portable generator is the most common recharge method, but they require a steady supply of gasoline to run. The noise levels can also disturb nearby campers. Recharcharging from your engine’s alternator while the engine is running can be the third method if your RV supports it.
Of the three recharging methods, a solar charging system requires no gas, makes no sound and can charge your batteries for hours and hours unattended as long as the sun is shining. Without sun, you’ll need to resort to one of the other methods.
Why Don’t RVs Come With Solar?
Solar charging systems are not standard equipment on most RVs. Why? Full off-grid solar charging systems are typically custom designed to an RV owners specific needs.
In a well designed off-grid RV solar system, all components are carefully selected and sized with the RV owner’s needs and style of camping in mind.
For this reason, I believe it would be a total waste of money to preconfigure an off-the-shelf solar system not knowing who the RV owner will be. Doing would also drive the sale price of the RV higher.
So I believe it’s best to keep solar as a custom option.
What RV manufactures often do is to pre-wire an RV for solar and call it SOLAR Ready.
If you buy an RV that is pre-wired for solar, chances are you or your installer will want to redo the wiring anyway to better satisfy power capacity and rating requirements.
What are the components of an off-grid RV solar system
There are several components needed to take your RV off-the-grid with solar. Solar panels, as I mentioned, are just one piece of the puzzle. You should really start with your battery bank.
1. Deep Cycle Battery Bank
The battery bank in your RV stores the electricity generated by the solar panels. One or more deep cycle lead acid or lithium batteries are connected together to simulate one large battery. Most battery banks provide 12 volts while some may be configured to provide 24 volts.
2. Power Inverter
The inverter converts DC power (from batteries) to standard household AC power. Inverter sizes and types vary considerably based on electrical system specifications. More sophisticated units (hybrid inverters) may include smart power switching capabilities.
3. Battery Monitoring System
Battery monitoring systems measure all power going in and out of your battery bank to tell you exactly how much battery capacity is available.
4. Solar Panels
One or more solar panels transform energy from the sun into electricity.
5. MPPT Solar Charge Controller
The solar charge controller is essentially your solar battery charger. It receives electricity from the solar panels and regulates it charge your battery bank. MPPT controllers offer the latest technology to charge your batteries in the most efficient manner possible.
6. Connection Equipment
These smaller components are used to tie the major components together and keep them operating safely. They include things like cables, connectors, fuses, cut-off switches, circuit breakers and junction boxes.
You can see how the cost of an off-grid solar system can really start to add up. So let’s look at some cost estimates.
How much does an RV Solar System Cost?
The cost of a permanently installed off-grid solar system can run from $1,500 for a very basic system up to $15,000 or more for a high-end system to run a residential refrigerator or air conditioner. Here’s why the “real cost” can get this high.
Having shared shared many tips on how to camp without hookups, I can say that many new RV owners are too quick to focus solely on having a solar powered RV. They miss the fact that solar panels are just one component in a larger off-grid system.
Let’s face it, solar energy is pretty cool. Which is why many new RV owners jump directly into pricing solar panels online trying to figure out “How many solar panels do I need to power my RV?” This is a mistake.
You should focus your battery power requirements first, then recharging sources (like solar panels and chargers) second.
Also keep in mind that the price and features available for each component vary considerably.
EXAMPLE #1 Batteries – A set of four decent quality AGM batteries may cost around $1,000 while a set of four LiFePo4 Lithium batteries will cost around $4,000. Some high-end systems capable of running AC units may have 6-10 lithium batteries priced at around $1,000 each.
EXAMPLE #2 Inverters – Power inverter features and prices will also vary considerably. A hybrid power inverter which automatically regulates and switchs between power sources can costs $1,500 – $2,500 compared to a $400 basic pure-sine inverter. The difference between 30 amp and 50 amp off-grid power inverter configurations can also be significant.
Finally, add in the expense to design a custom system and install it on your RV. You can cut labor costs if you’re a qualified do-it-yourselfer.
Is it worth it? Most RV owners who boondock frequently with solar would tell you that it was worth the money. As a frequent boondocker, I can say that the freedom and convenience that an powerful off-grid solar power system provides is a total game changer.
At the end of the day, YOUR individual power needs will ultimately determine the size, cost and components you’ll need. There’s no one-size-fits-all solution.
Here are three typical solar system configurations
The ballpark estimates for these systems are for major components only and do not include labor.
1. Basic Off-Grid Solar System
This setup can power basic small electronics like lights, laptops, mobile hotspot, TVs, and cell phone booster.
- 220 Ah of flooded deep cycle batteries
- 200-300 watts of solar panels
- 1,500 watt pure-sine inverter
- 20 Amp MPPT Charge Controller
Cost of components: $1,500 to $3,000
2. Typical Boondocking Off-Grid Solar System
This setup can power small electronics plus periodic use of a microwave oven, coffee maker, hair dryer, electric blanket.
- 450 Ah of flooded deep cycle batteries
- 400-600 watts of solar panels
- 2,000 or 3,000 watt pure-sine inverter
- 30-50 Amp MPPT Charge Controller
Cost of components: $4,000 to $6,000
3. Large Power Load Off-Grid Solar System
This type of setup can power a residential refrigerator 24/7 plus other essential equipment.
- 600-800 Ah of lithium batteries
- 800 to 1000 watts of solar panels
- 3,000-4,000 watt hybrid inverter
- 60 Amp MPPT Charge Controller
Cost of components: $12,000 to $18,000
Is solar worth the investment?
If you are a new RV owner I recommend using your RV for a while before making any major upgrades. Over time you will figure out what your camping preferences and limitations are. Then you’ll be in a better position to decide whether an investment in solar is something you’ll benefit from.
Experienced RV owners will probably already know whether they need solar or not.
If you feel camping off-the-grid is something you’re interested in, then I encourage you to try it out first before making a significant investment in solar or generators. Here are some boondocking tips to get you started.
Consider starting out with a portable solar panel kit like one of these available on Amazon. There is no permanent installation required and they provide plenty of power to keep your batteries charged. Just store the portable panel when you don’t need it.
You could even create your own portable solar battery charger. Building your own is a fun way to learn the basics of solar. Here’s a simple project video showing how to build a basic portable solar charger.
How Can Off-Grid Solar Expand Your Camping Options?
Being self-contained and self-sufficient in your RV will enable you to stay anywhere you’re allowed to. Not having to rely on full-hookup campsites means you can take ANY campsite or find FREE camping options.
There are many beautiful campgrounds located on public, National Park, or State owned land. Camping at these campgrounds is inexpensive and often free. But, what you gain in beautiful scenery and solitude you lose in amenities.
When we first started RVing, we primarly stayed in RV parks. We didn’t even consider locations that did not have full-hookup sites. Over the years our preferences have changed. We still stay at RV parks periodically, but prefer to seek out more scenic locations that offer more privacy.
We enjoy the freedom and sponteneity of not having to make reservations. We often just hit the road not knowing where we’ll end up.
At first my wife was a bit uncomfortable with the idea of being off-the-grid and having to sacrifice too many creature comforts. These days she is totally on-board with boondocking without hookups. Here’s a fun video of Melissa and I sharing our evolution from RV park camping to boondocking.
Do you need a generator if you have solar?
There will be times when you’ll want to run a generator. Solar is not going to recharg your batteries on rainy days, through dense clouds or when camped in the woods. This is when a auxilliary generator comes in handy. A generator can also power an air conditioner, heater or other power hungry appliance when you’re battery bank and inverter can’t.
There are cases when some have abandoned their generator completely and made the necessary adjustments for living solely off of solar.
If you have a residential fridge or need to run and air conditioner, having a generator as a backup is recommended.
Our energy needs are pretty light and we only boondock in locations with a moderate climate. So we have less of a need for a generator. Solar is our primary source of battery charging and our motorhome’s engine is our second.
What can you power with solar?
The solar panels on your RV are used mainly for battery charging. Therefore, the amount of power (electrical load) you can draw is determined primarily by the capacity of your battery bank and inverter, and NOT by the amount of solar on your roof.
This is a common misconception people have when they ask “how many solar panels to I need to run my whatever?” Instead they should ask “how much battery capacity and what size inverter do I need to run my whatever?”
Lights (preferably LED), laptop computers, radios, fans, TVs, water pump and other small items can be used while on battery/inverter power. In some cases small coffee makers, low power microwave ovens, toasters, and low power hair dryers can be used for very short periods depending on your battery capacity and invterter size.
High power consumers like air conditioners, heat pumps, space heaters, or water heaters generally require more power than a standard RV solar/battery/inverter system can provide.
Power hungry components like those will rapidly drain your RV batteries. For this reason, most RVers who rely on solar move throughout the year to sunny locations with moderate climates. Keeping cool means opening windows and/or turning on an electric fan, not running an air conditioner.
Is it possible to run an air conditioner off of an RV battery bank? Yes it is. Is it a practical solution? Usually no. Even as more RVers opt for lithium batteries it’s still good practice to use your energy efficiently.
An RV powering their AC unit while boondocking used to be an anomaly. More and more people now have the ability to run an air conditioner with the help of large lithium battery banks, soft-start devices, and highly efficient AC units. It certainly isn’t mainstream by any means. So, for now, I’d stick with the “if you can’t stand the heat…get out of the desert” approach.
Residential refrigerators are large power consumers that run 24/7. So if you’re looking to buy an RV with a residential refrigerator, just know that boondocking will be challenging. You’ll need a large lithium battery bank and large solar array.
Experiment and determine how much power you need?
The best way to figure out what your needs are is to just go do some dry camping for a few days while measuring your power usage. This is an essential first step to figuring out how much power you need while out camping.
To get an accurate indication of your state of charge, you will need a good battery monitoring system (BMS). Without one, you’ll simply be guessing and probably guessing wrong. Keep in mind that the battery voltage or level gauge that came with your RV with will NOT give you an accurate measure of your battery state-of-charge (how much reserve power available).
Here’s what you do. Fully charge your battery bank. Then take your RV dry camping and watch that battery monitor. You won’t need solar panels for this experiment. Just use your RV and see how long it takes to get down to 50 percent of available capacity (if using lead acid batteries). Can you make it through a 24 hour period? When you reach 50 percent, well that’s all you’ve got. It’s time to recharge your battery bank.
Take note of the equipment you’ve used and for how long. Here are some tips to help you calculate and understanding your RV battery capacity and power consumption. If you need more power, add more battery capacity and try again.
Try to get through a good 24 to 48 hours before you need to recharge. Everybody’s needs are different, but having enough battery capacity for at least two days is a good benchmark to start with.
Keep that 50 percent of battery capacity in mind b (i.e. flooded or AGM batteries). 50% is your “usable” capacity.
EXAMPLE: If your 200 amp hour battery bank gets down to 50 percent in 24 hours, then you’ve used approximately 100 Amp Hours of capacity during that time. So if you need 200 amp hours to live, then you’ll need a 400 amp hour battery bank.
Once you’ve figured out how big your battery bank needs to be, you’ll have a good idea of how much solar you will need to keep those batteries charged up.
Do you have lithium batteries? If you do, then ignore the 50% rule. The usable capacity of most lithium (or LiFePO4) batteries is between 80 and 100 percent of the battery’s rated amp hours. This means you can repeatedly use 80 to 100 percent of the battery capacity without damaging the battery (ask your battery manufacturer for the exact numbers).
A simple way to estimate how much solar power you’ll need is to apply the 1 Watt to per Amp Hour rule. Simply put, your maximum solar output (in watts) should equal your battery capacity (in amp hours).
EXAMPLE: A 400 Amp Hour battery bank will need roughly 400 Watts of solar. This is just a rough measure to get you in the ball park. You should also take into account the efficiency of your panels, amount of sun in your area, cable size/length, and power loss between your solar panels and batteries (i.e Voltage Drop). I recommend adding at least 20 percent to the solar estimate to account for these factors.
Continue Reading about RV Solar
That should get you off to a good start. When you are ready for more, these articles will help you take it to the next level. I’ve also put together a FREE Guide To RV Solar Panels that is packed full of more useful information. You can download it here.
- How We Took Our RV Off-The-Grid with Solar
- How Much Battery Capacity Do You Need?
- What Battery Monitoring System Should You Buy?
- What Kind of Solar Panels Should You Buy?
- Off-Grid Solar Charging System Components
- Choosing the Right Solar Charge Controller
- Using a Power Inverter to Generate Off Grid AC Power