So you want to live in a van (or RV) in beautiful places where you can camp for free, “off grid” as they say?
You know you’ll need solar but all of the calculations on how much you need are a bit baffling, and maybe you’ve never wired anything before in your life. Maybe you feel certain you can figure it out, but trying to digest all of the information is overwhelming. This is exactly where we were at several years ago. Through much trial and error, and help from more knowledgable friends, we’re reliably soaking up a sunshine’s worth of free power. I’ve done this three times now, on different vehicles, and this article is here to share that information in as simple a way as possible.
We’ll cover how much you need, based on what we believe is the “standard” RVer / vanlifer’s needs. We’ll cover all of the parts you’ll need (it’ll cost under $2000) and then show you exactly how to hook it up. When you’re finished with the instructions in this article, you’ll be able to live off the grid indefinitely for years. Or, until the sun burns out, whichever comes first.
Stupid Disclaimer: Please note that I am not a licensed electrician and this is all information provided freely, with the best intentions of accuracy, and without limit to the amount of errors I have made (both with the article, and perhaps on a grander scale, life in general). However, it absolutely does work, there’s nothing overly dangerous here given it’s almost all 12v and more or less a plug and play affair these days. That said, you will have to use a scissor, twist minuscule sharp wires together, and maybe even climb onto the roof of a vehicle. Should you choose to operate a ladder, please consult the picture of the guy falling off with his paint bucket on the top not-a-step.
How Much Solar Do I Need?
I won’t bore you with complicated calculations. The following is what we imagine most vanlifers, truck campers or small rig RVers use on a typical basis, and if you think you’ll be in the same boat, you can simply look the list over and proceed to the next section.
- A fridge. Try and aim for one that is as small as you can handle and draws less than 3amps. Note that we have–and the system about to be explained is based on–a very small fridge. 63 quarts to be exact. The average “not big” fridge in a home is around 450 quarts. So, there’s that… but don’t fret, we have options for you if this is a deal breaker and also…well…vanlife usually means a small fridge.
- A fan or two. Ours take .12-.35A depending on the intensity of the fan setting. It’s an advanced 1 – 3 speed system, whereby the higher the number, the more wind you get. What can’t they do these days?
- An iPad. 2.1/2.4A For the viewing of movies, playing Mario Run and the occasional wacky video made by our own in-house YouTubers (videos only available over local access, sorry.)
- A couple of iPhones. 2.1A each using the charger box, varies by USB port using just the cable.
- A MacBook. 2-3A but you’ll need an inverter for most laptops (and probably the swankiest tablets too.)
- Some type of LED lighting system. Ours consists of two overhead LED lights, and one above the bed, for a total of .5A.
And you may have wireless earbuds and an electric shaver, a blow dryer or blender, too. We have our own random small things–especially with kids around the holidays and their birthdays–which need charged. You can do the math on how many amp hours each of these will take, but in our experience, somewhat oversizing your system will be the way to go. Maybe you’ll need to rethink how often your hair can be wet or your 5 o’clock shadow can roll into 48 hours, but these are typically more random devices that you don’t have to consider every last amp for.
Going a little bigger than you need also future proofs you when you realize you really need some additional stuff charging up or running regularly. For example, maybe the cool kids convince you to take up vaping or you realize that you don’t know how you’ve lived life before without an electric bicycle on the roof of your van.
This is also where Debby comes in and says, “Well, my husband is goin-ta want more fridgidair size than that. We keep at least a pound of mule buck in the freezer most times.” Or pizza rolls or pre-mixed vegan smoothy bars or whatever you particularly make certain you don’t run out of in your own life.
Or when you know you’ll have two computers rolling at once, because you’re an up-and-coming superstar and so is your girlfriend.
The system we’re building here will be enough to handle one or two upgrades, but even if you wanted everything listed here, both of those laptops and a fridge sized to hold a half keg of Coors Light, you should be able to do so without any additional effort than what this system can reliably put out. And the great thing about solar is that you can just add another battery (costly) or panel to the roof (if you have space, but less costly) and start stealing the sun god’s power to your satisfaction once more.
Want to meander through some more details on figuring out how many amps you specifically need, which devices we have chosen to use in our van and how much power this is all going to take? Read on…
Easily Determine Amps for a Device
Many devices will just list out how many amps they use. If they’re a 12v device, this is made clear, sometimes accompanied by a 24v listing as well. If they can switch between 12v DC and 110v AC, they’ll usually list both. If they don’t, but they list the watts, the formula is easy.
Watts ÷ Volts = Amps
So, if your device lists 12 watts, and we’re working with a 12v system, then that device uses 1 amp.
Simple enough? Now all you really need to know is how many Amp hours you’ll use…
Amp Hours Simplified
Imagine your battery bank (we’ll get to this in a moment) as a bucket. The number of Amp hours (Ah) your battery can store is essentially how large your bucket is. Batteries often come in 50Ah, 100Ah, etc. varieties.
To know how big of a bucket, aka Ah we need, we can do some simple calculations on the devices we’ve outlined above.
The Fridge: Engel AC/DC Front-Open
We more or less have this fridge, though ours is the previous model. We’ve had this small refrigerator since 2016 and it has worked perfectly for us, though the reviews on Amazon say differently. The current model draws a max 2.8amps. You’ll likely want your fridge on 24/7, but it won’t literally be running 2.8amps every minute of the day. Ours runs about 1/3rd of the time, that is, it makes the noise that indicates it’s cooling for a total of about 8 hours per day when you add all of the time up. So, the math:
2.8 Amps x 8 hours = 22.4Ah
Side note: We chose a front opening fridge for the convenience. We know that many a vanlifer will swear that only the top opening fridges–like a cooler–are the only way to go, but I live in a van with three small boys, my wife and I, and when I want to grab something out of the fridge I have no desire to slide it out, waste space, or dig all through to the bottom to find something. Do as you please, of course, but this is our reasoning. Because, you know, someone will just be dying reading this… 🙂
Two Fans: Sirocco II
We’ve had an assortment of fans in our life, mainly purchased from auto parts stores in desperation while living in Mexico during the summer. During a remodel this past summer, I bought two of these fans. They’re good looking, push a decent amount of air and not only swivel to allow you to point them in any conceivable direction, but also fold up out of the way when you’re not using them. They also have a timer option, so you could theoretically set it to turn off awhile after you leave your van or fall asleep I suppose.
They take .7 amps between the two. My wife will run them all night long, and for most of the day when we’re not driving or out exploring. The math:
0.7 Amps x 20 hours = 14Ah
iPads & iPhones
We have the iPad Pro, which draws ~2.25A, plus two iPhones which draw 2.1A using the cord and the wall plug. If you just use the cord, and plug directly into a USB outlet, the USB outlet will typically indicate if it’s using .5A or 2.1A, etc. As noted before, we want a system that will handle whatever we throw at it, so lets say 2.2A x 3 for all of these devices. The math for one iPhone, though:
2.1 Amps x 4 hours (charging time) = 8.4Ah
For two of them, that’s 16.8Ah.
For those interested, we currently have an iPhone Xs and an iPhone 8.
And then the iPad:
2.25 Amps x 4 hours (charging time) = 9Ah
Ours is a MacBook Pro, which I use for work around 6 hours / day, 4 days per week. That’s 32 hours total, or about 4.6 hours / day on average. Math time:
2.5 Amps x 4.6 hours = 11.5Ah
As mentioned previously, our lights use .5A total. This is a trickier one to figure out, since in the summer we may use our lights for 2 hours and in the winter, when the sun sets closer to 5pm, 6 hours. Let’s balance it all out and estimate using our lights for 4 hours / day, every day.
.5 Amps x 4 hours = 2Ah
So all told, we’re using:
22.4Ah + 14Ah + 16.8Ah + 9Ah + 11.5Ah + 2Ah = 75.7Ah
Since we’ll need 75+Ah to run the devices we have now, we’ll shoot for a 100Ah battery bank. Which leads us to our next step…
What All Equipment Do I Need?
Now that we know how many Amp hours we’ll need, we can get into the details. These are going to be the basic components of our solar system:
- Solar panels, which soak up the sun.
- Charge controller, which literally controls how the energy from the panels and battery interact, as well as showing you valuable info on the status of your system.
- Wiring, for connecting it all.
- Fuse box, which isn’t completely necessary, but is good to have.
- Battery, to store the power so you can use it at night or when the sun is hiding.
- Inverter, so we can use high powered devices like laptops.
Let’s review them one at at time.
Solar Panels: 320 Watts Total
With the setup above, 320 watts of incoming solar should be enough to keep us running smoothly, assuming we get plenty of sun–especially the good stuff, from around 10am – 3pm. This requires a few lifestyle choices, like not camping in the shade and hoping it isn’t 100% cloud cover for days. I do enjoy some shade, but that’s what the fans are for, and it is not particularly my goal to camp in rainy places for long periods of time if I can help it.
What to Buy: We use two 160watt Renogy flexible solar panels. I like the flexible panels for their slim profile, lightweight and they’re easy to just literally tape directly to your roof (no holes in the roof required) with this VHB tape. That may sound crazy, but it works and many a vanlife DIYer has relied on this stuff for years, including us.
You can run the wiring for the solar panels through a hole you cut in the roof, or we’ve even simply done it through a small hole in a pop top or directly through a window (that you’ll then need to leave cracked open, forever.) Or you can buy one of these roof ports to make it all a bit cleaner. We have the two port, though we’re only using one, just in case we need to expand things further in the future.
If you do buy that port, you’ll then need the Renogy to ZAMP adapter.
Otherwise, you can just buy wire that plugs directly into the solar panels and which you can wire into your solar charge controller.
Solar Panel Pricing: $543 – $605
- Two 160watt panels: $500
- Solar extension wire: $20 for 10′, $30 for 20′. You’ll need this for both sides of the charge controller (see next section) so best to buy the length you need and you can cut it to suit from there.
- Y Connectors, for connecting your two solar panels together: $9
- VHB tape: $14
Charge Controller: 30amp
We have had many charge controllers. The original controller by Renogy, which came with our first panel was very basic and provided little information on the health of our system. We later had a Moohoo controller, which did the job just fine, but I currently love our latest charge controller and fully expect it to last for years, the ZAMP ZS-30A. It’s great because it actively shows you remaining Ah, current volts, whether you’re fully charged or not, the state of your battery and more.
You’ll also need an inline 40 amp fuse for both the incoming hot wire (which is the red one under “solar extension cables” in the previous section) and the one connecting the charge controller to your battery. You can get a pair of these here for $9.
Charge Controller Pricing: $149
- ZAMP solar charge controller: $140
- Two inline 40 amp fuses: $9
- Solar extension cables, see #2 in the previous Solar Panel Pricing section.
Battery & Fuse Box
You can put the necessary fuses for your devices inline if you’d like, with little inline blade fuses that are similar to the ones mentioned in the Charge Controller Pricing section. But for $12 (fuses not included) we sprung for this little fuse box that lets me see immediately if a fuse is blown (a red light on that terminal lights up) and just makes things neater.
The big expense here is the battery. There are dozens, if not hundreds, of comparisons between lead acid batteries (the one that’s most likely in your vehicle’s engine compartment and that you’ve recognized as a “car battery” or “deep cycle” battery all of your life) vs. lithium batteries (referred to specifically as LiFePO4 these days.) We used lead acid batteries for years. Using two 50Ah lead acid batteries, which cost $250 each, they lasted us approximately 2 years each.
This time around, we opted for one 100Ah 12v LiFePO4 battery from Battle Born. Let’s ignore the greater toxicity of lead acid and the fact that you may only get 40Ah (or less, our year old lead acid battery sometimes only registers 33Ah) out of a 50Ah rated battery and just compare the costs over time.
Two 50Ah lead acid batteries x $250 = $500.
You’d replace these at least twice in 8 years, so the full cost would be $1500.
One 100Ah LiFePO4 battery x $950 = $950.
Battle Born’s are guaranteed for 8 years at full replacement. We also got ours for $859 since we were Escapees Members. Not sure how long that deal will last but if you are also one of these folks, just call Battle Born with your SKP # and they’ll give you the discount.
While LiFePO4 are much more expensive up front, they’re going to save you $550 over the course of 8 years. It was hard for us to drop that initial cash, too, but well worth it in the long run. Plus, Battle Born’s warranty is actually 10 years, they just give you a prorated amount after year 8. I also keep our batteries inside of the van, which is a no go with gas-emitting lead acid batteries. One of these also takes up a bit less space, and is significantly lighter, than two lead acid batteries.
Battery & Fuse Box Pricing: $1002
- Fuse box: $12
- Battle Born 100Ah 12v battery: $950
- Blade fuses: $5 at an automotive store
- Wire: $15 at a hardware store
If you’re going to run a laptop, or even many tablets these days, or just need a standard 110v AC plug (the standard plug you have in a house) then you’ll need an inverter.
We barely survived using cheap 100w inverters, even a 250w inverter, like you’d buy from Auto Zone. But it’s not realistic to work from a laptop for multiple hours a day with these, they could never keep up with our MacBook Pro and likely most other laptops.
So, we got the 700w inverter from Renogy and have never looked back. This is also probably the simplest part of the installation process, as the inverter attaches directly to your battery and you’re ready to go!
Inverter Pricing: $135
That puts our total cost for the solar system itself at $1905.
How to Put it All Together
The first thing to know about 12v is it is much easier and infinitely safer to work with than messing with 110v AC like you’ll find in the average American home. Don’t fool with that stuff without disconnecting all of the power, always, but we’re not discussing AC power here today, outside of the inverter, which doesn’t really require you to do any wiring.
Anyone who can twist wires together, drill a hole or two and turn a screwdriver can do this. Under nearly all normal conditions, you can’t get shocked by 12v. You can however, short things out by crossing the wires, so be careful of that.
Installing the System
First thing, set your two panels on your roof to make sure they’re both going to fit where you want them. Depending on what else is on your roof, and where you plan to put the battery bank, this is important. You don’t want to start attaching panels only to have to move them. Even with the VHB tape we recommend, it’s a pain to get it back off once you’ve put it down.
You may also want to put your panels as close to where the battery bank will be as possible, so you need to use as little wire to connect everything. Consider this overall layout of the wiring for your new solar setup, and then look in your own rig and determine where these components might ideally fit.
So what do we have here?
- Two solar panels attached to the roof with VHB tape.
- The wires that come attached to each of the panels (for a total of 2 red wires and 2 black wires) routed to the Y-connector.
- Installing the roof port (skip to #4 if you don’t plan to use one):
- You’ll need to drill a hole in the roof of your vehicle to install the roof port as per the manual that comes with it.
- From the Y-connector to the roof port, we’ll need to use the additional solar wire and connect that to the port with the Renogy to ZAMP adapter.
- From either the roof port, or directly from the Y-connector if you’re not using a roof port, run the black and red solar wires to the charge controller. The charge controller has four places to attach wires. Two of them are inputs, which you use in this step.
- Next, run a black and red solar wire each from the charge controller directly to the battery. Be sure to put the red wire on + positive and the black wire on the – negative terminal. If you opted for a lead acid battery, and it has four posts, two are negative and two positive. You can use either of them (though you still need one positive and one negative). Typically, the smaller ones are easier to attach wires.
- To hook up a fuse box, you run a red piece of solar wire from the large terminal on the fuse box (it’s not beneath the plastic if you bought the one linked to in this article), directly to the battery’s positive terminal.
- If installing the 700w inverter, you run the black and red wires to the negative and positive terminals directly on the battery.
- Once that is all setup, you can wire your devices to the fuse box and battery.
- Red / positive wires (they’re not always red, it depends on the device) from each device go into the various ports on the fuse box. You take your positive wire and attach a female quick connect which allows you to just slip the wire onto the fuse box. Then, add a fuse to that slot. What fuse you’ll use depends on the device, and should be listed in the device’s manual somewhere.
- Black / negative wires can all be combined with a twist-on wire nut like this, and then an extra one to run from the wire nut to the battery’s negative terminal.
That’s it! Your charge controller should fire up. With the ZAMP controller, there’s a button to set it to LiFePO4 batteries, which is important to do as well.
At this point, your devices should be running, the charge controller should be showing the status of your battery, etc.
If it’s not…
- If the charge controller shows nothing, make sure the connections from the controller to the battery are solidly connected at both the battery and controller.
- Did you get the + and – wiring correct? If you always use black for negative ( – ) and red for positive ( – ) that makes it easier to trace them back to double check.
- If it’s still not working, you may not have needed to reverse the polarity, or you may still need to do so. The Renogy to ZAMP adapter comes with two polarity reversers. You typically have to use one, but if you already plugged that in, try removing it and vice versa.
- Does the battery actually have power? You can test by connecting a device directly to its positive and negative terminals.
Other Things You May Need
Nothing in this section is required, but it can all make your life a bit easier or help you get your batteries charged back up if you don’t have access to good sun for awhile.
If you installed the Renogy 700w inverter, it comes with two AC outlets and two USB outlets. This may be sufficient for your needs, but if you want to have an additional USB outlet elsewhere in your rig, we use this one and are quite happy with it. You just connect it as outlined in the last of the 8 steps earlier in this section (negative wire to battery, positive to fuse box) and this one has quick charging 3 amp USB outlets which are fine even for devices that require fewer amps.
You may also want to use some switches like this one so you can turn things on and off. For example, if you hook up a water pump, it’s nice to be able to turn it off when you’re not using it. Same for LED lights that don’t come with a switch built in. You could also get a switch that turns the entire system off, though disconnecting the red wires from the battery will do the same thing.
Finally, you may want to have the ability to connect to AC power to charge up when it rains for 8 days straight, or you just find yourself at an RV park. To do this, we just used a standard multi outlet surge protector like you might have at your home or office. Then plug that into an extension cord and you can plug into any standard outlet at a friend’s house. For some RV parks which don’t offer that standard outlet (called 15amp), you may also need a 30amp adapter like this one. If you want to be extra careful, one of these 30amp surge protectors, too, though we don’t use one.
Finally, if you want to actually charge the battery when connected to RV park “shore power” you’ll need something like this.
Still confused? Feel free to get in touch with us and we’ll be happy to help in any way we can!
All that you need to do from there is find a sunny spot to call home and, should you choose, keep on truckin’!