Want To Use Solar Panels But In A Stealthy Way?
People go camping, or sleep, in all different type of places. We don’t necessarily want to advertise that to others though, and that’s why it’s called stealth camping.
Stealth camping means camping, or sleeping, in places where most people don’t go to camp. It can be in a parking lot, on the street, by a school or a church, or even a construction site.
Related Product: Looking for portable power? My favorite power station right now is the EcoFlow Delta Max (click to view on Amazon)
A stealth camper doesn’t have to be different than a regular camper, except from what the camping setup looks like on the outside.
Inside the van, car, or whatever you plan to sleep in, you probably need to keep your devices charged and powered just like the rest of us.
So how do you harness the radiation of the sun to generate electricity in a stealthy way? That’s what I am going to tell you today.
What You Need To Know
What you’re going to need depends on what type of setup you have.
Use with portable power stations
If you plan on using the solar panel(s) to charge a portable power station, also known as a solar generator, you should not use a solar charge controller.
Most portable power stations have charge controllers built-in and you don’t want to use two charge controllers.
Use with 12V battery
However, if you have a regular 12V deep cycle battery, you need a solar charge controller between the panel and the battery.
Power stations I talk about above do also use 12V batteries, but they have more components than just the battery itself, like an inverter and a charge controller.
The solar charge controller will regulate the voltage and charge the battery safely. Which size and type of charge controller depends on the battery you have.
If you want me to help you find one compatible with your panel and battery, please leave a comment and tell me as much as possible about your setup.
The basics of volts and amps
If you look at the specifications of a solar panel you will see a lot of numbers that can be hard to understand.
What matters the most when choosing a panel for a power station or a charge controller is the open-circuit voltage (VOC) and the short-circuit current (ISC).
As an example, if we take a look at the specifications of the popular Jackery Explorer 500 (click to view on Amazon).
It tells us that the DC input is an 8mm DC port, connected to a charge controller that accepts voltages between 12 to 30 volts and up to 100W max.
Or if you’re going the charge controller route with something like the Renogy Voyager 20A. In its specifications the rated charge current is 20A, and the PV input voltage range is 15-55V.
Now that we know what the power station or the charge controller can handle, we can take a look at a panel.
The flexible Renogy 100W (click to view on Amazon) is a popular one, and it has a VOC rating of 22.5 volts, and an ISC rating of 5.75 amps. I had to visit Renogy’s website to find the ISC, but it’s usually listed on the Amazon listing.
Since the VOC rating is within the 12-30V and 15-55V, it’s compatible with both type of setups.
You should never exceed the max input voltage of the charge controller. This will cause damage and can be dangerous.
What about the amperage? Well, Jackery doesn’t recommend going over 100W. And while you should stick to what the company says for warranty reasons, I have used two 100W panels with my Explorer 500 for years now without issues.
The Renogy Voyager is rated for up to 20A, or 260W in a 12V setup.
You’re not going to destroy it if you connect 300W or likely not even 400W (although I suggest talking to Renogy before doing that), because the charge controller will regulate the amps. Any amps over 20A will be wasted though.
Our setup have a couple more requirements in addition to being able to generate electricity.
Here are the main ones:
As thin as possible
The thinner the panel, the harder it is to see. Sure, if you’re mounting a panel on a small Toyota Prius people are going to be able to see the roof of the vehicle and the panel, but on a taller car, truck, or van it won’t be as easy.
As light as possible
Weight matters to travelers whether you have considered it or not. The heavier the setup, the more fuel it’s going to take to travel.
But it also matters here because car roofs aren’t made to take a lot of weight, and when you add several panels the weight adds up.
Easy to secure
The thinness isn’t just important when it comes to the panel itself, but also in how we secure it to the roof of the vehicle.
Solar panels can be heavy and require thick mounts, and that’s a big no-no. Therefore we need one that’s light and easy to secure, preferably without screwing into the roof.
A non-waterproof solar panel shouldn’t be mounted on a roof, for obvious reasons.
It needs to be a panel that can handle all types of weather. Low quality panels can’t handle a lot of either heat or cold, and then you end up replacing the panel within a year or two.
The solar panel
The type of solar panel we need is what is called a flexible panel. These are thin, lightweight, usually waterproof, and easy to secure to a roof.
There are a lot of different brands to choose from, but I recommend sticking with a reputable brand like Renogy, Newpowa, and Topsolar.
Here is a table with a couple of different panels that I recommend.
One of the pros with flexible panels is that they are lightweight, which means that they are easier to mount than rigid panels.
Rigid panels weigh a lot and often need to be secured to the roof with screws, while flexible panels can be taped or glued down.
I recommend securing flexible panels to roofs with EternaBond tape which is usually used to seal roofs.
It’s easy to install and will keep your panel secured to the roof.
Some people use double sided VHB foam tape by 3M.
The 3M tape is also easy to use and will hold a panel in place.
Of course, you could also just set the panel on your roof during the day temporarily and not secure it. This way you could pull the wiring through a window instead of having to drill a hole, but this is obviously a less stealthy way to do it.
When it comes to the wiring it depends a lot on what your setup is going to look like. If you have a power station, the wiring needs to lead directly to a MC4 to DC adapter which then plugs into your power station.
If you have a regular deep cycle battery, the wiring from the solar panel need to connected to a charge controller in your vehicle, then connected to the battery.
You are likely going to have to drill a hole in the roof of your car or van to pull the wire through. If you have an RV or van with a fridge vent, you can pull the wire through it instead.
The solar panels I recommend above use MC4 connectors, so the hole needs to be large enough to pull the connectors through unless you want to only pull the wire through with an extension cable like this one by BougeRV (click to view on Amazon).
One great way to pull wires through a roof is with an entry gland, like this one by Renogy.
By using an entry gland, it will not only look better but most likely seal better. All you have to do after drilling a hole, pulling the wires through the gland and the hole, is to seal it off. Renogy recommends using Sikaflex 252 sealant (click to view on Amazon).
After pulling the wires through, you can either connect the bare wires to the charge controller if you’re going to charge a regular 12V battery, or install MC4 connectors on the wires with an MC4 solar kit like this one by Iwiss.
The newly installed MC4 connectors will then connect to the MC4 to DC adapter before being plugged into your power station.
Frequently Asked Questions
Which MC4 to DC adapter do I need for my power station/solar generator?
It depends on which model you have.
Jackery uses mostly 8mm, so then you need an MC4 to 8mm adapter.
Goal Zero uses both 8mm and Anderson PowerPole (they call it High PowerPort), so then you need an MC4 to Anderson adapter.
EcoFlow uses XT60 connectors and include an MC4 to XT60 adapter with most of its power stations.
If you have a different brand, please leave a comment and tell me the exact model and I’ll help you as soon as possible.
How do I combine two or more panels?
Panels can be combined in either a series or a parallel connection.
With a parallel connection, the voltage will stay the same but the amps will add together.
A parallel connection is made with an MC4 Y branch. These come in different sizes depending on how many panels you want to connect.
If you combine several panels, you need to make sure that all the connectors and wires can handle the total amperage of the panels.
A series connection does not require any extra adapters. You simply take one positive MC4 male connector from one panel and connect it to the negative MC4 female connector on the second panel.
What this does is it adds the voltages together but keeps the amps the same. You should only do a series connection if you are sure that the power station or charge controller can handle the total voltage.
Here is how the two different ways results in different voltages and amps.
Parallel: Two 12V 100W panels (18V, 6A) wired in parallel with an MC4 Y branch = 18V, 12A
Series: Two 12V 100W panels (18V, 6A) wired in series = 36V, 6A
If we use the same power station example as earlier, the Explorer 500 which has a 12-30V limit, we can tell that the only way to combine two 12V 100W panels for it is via a parallel connection. A series connection equals more than 30V, which the power station won’t accept.
The symbol on the MC4 connectors is a minus (-) even though it’s a positive red cable?
The symbols on the MC4 connectors themselves don’t matter, they’re just made like that in the factory. Follow the wiring and make sure you’re connecting positive to positive (unless you are combining panels in series).
Please leave a comment down below if you have any questions.