Does setting up your ambo for off-grid solar power seem too expensive?
Let’s look at how to build a simple system for under $1000.

If you’ve been cruising social media looking at off-grid solar systems it would be easy to think that you have to spend some serious $$$ to get set up.  While it is true that a high performance system designed to handle heavy loads under rough conditions is expensive, a simple system that will power the basics doesn’t have to be much money.

For my first off-grid solar back in 2019 I only spent about $600 as my ambulance already had an inverter and two AGM batteries that were configured to only power the box.

So, if I had a tight budget and was starting from scratch here’s what I’d do:

Step 1: Determine Your Power Needs

Before purchasing any components, it's crucial to understand your power needs. Make a list of all the devices you plan to use, note their power ratings, and estimate how long you'll be using them each day. This will help you to figure out the size of the system you need.

Some important things to consider.

a) how often will you be driving and for how long?  If you are driving every couple days then you might not really need solar.  A 100AH Lithium battery will run fans, lights, charge phones, laptops and run a small fridge for 2-4 days. It might make more sense to get a higher capacity DC to DC charger.

On the other hand, if you drive infrequently or only for very short distances then you’ll need more solar panels and a DC to DC charger might not be essential.

b) The less power you use, the less you have to spend.  The best way to keep costs down is to keep your electrical usage down.

c) Do you really need an inverter?  So many devices that we plug into the wall for AC power actually use DC power.  Phones, Laptops, CPAP machines, etc.  A few inexpensive DC power converters might save you money and power.  Here’s a video that explains more: 

Step 2: Purchase Your Components

For a basic solar power system, you will need a few core components:

  • Solar Panels: These are your power generators. They come in different wattages and types. For budget concerns, a 100-watt polycrystalline solar panel is a great starting point.

These 200 watt panels are only $180 each right now.

  • DC to DC Battery Charger: Most ambulances come with high output alternators. Don’t waste that power. A DC to DC charger serves several purposes. a) it protects your lithium battery by providing the correct charging profile (not the same as what works for lead acid batteries). b) it prevents your auxiliary battery or batteries from discharging your starting battery and c) it will charge your auxiliary batteries when the sun isn’t shining and reduces the need for a really big bank of solar panels.

    The $99 Renogy 20 Amp DC to DC charger is a decent low budget option.


  • Wiring and Connectors: You'll also need wiring to connect everything together and MC4 connectors to link your solar panels to the charge controller.

    Here’s a basic solar panel wiring kit to get things started. Only $19.


  • Fuses and Switches:  You need a large DC switch and also a large capacity DC fuse that’s rated to match your battery size.  It’s beyond this short article to detail how to size them but here’s links to hardware that I’ve used.

    200 AMP DC fuse
    DC Battery Switch

Step 3: Install Your System

  • Installation will vary a lot according to what components you have and which ones you buy.  I’ll add some good learning resources below.

    One thing I strongly recommend.  Getting the right tools does make things a lot easier, faster and safer.

    Save your fingers, and work faster with a proper wire stripper:

    Wire Stripper & Crimper $21 

    A multimeter is an essential piece of equipment if you own an ambulance. It doesn’t have to be expensive but it can save your hours of guessing or hundreds of dollars in having someone else diagnose your electrical issues.

    Budget MultiMeter - $16

    High Quality MultiMeter - $100

    Properly connecting and splicing wires is essential. Don’t accidentally burn your camper to the ground due to an electrical fire.  Here’s two things I depend on:

    Solder Seal Wiring Connector Kit $26 (no more ugly wiring connections)

    Heat Gun $18 (for heat shrink, solder seal connectors and more)



Step 4: Wrapping Up

Note: This guide is intended for informational purposes and assumes a basic understanding of electrical systems. Please consult a professional if you're unsure of anything.

Before you start using your system, it's vital to test it. Check the voltage at various points in the system to make sure everything is working correctly. (Another good reason to buy that Multimeter).

It’s beyond the scope of this little article to detail how to install or test an offgrid solar system but I’ll add educational resources and eventually a list of installers.


Educational Resources:


Will Prowse YouTube:
Explorist YouTube

About my Ambo Camper:
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My personal Campulance is a 2009 Ford E350 with the Powerstroke 6.0 and a Crestline New Era box on it. It has the dual alternator option and can output a maximum of 320 amps.

My current electrical system:

A single 280 amp hour lithium iron phosphate battery.
Two 100 Watt Solar Panels (renogy)
A 30 Amp MPPT Solar Charge Controller
A 60 Amp Renogy DC to DC Charger
A 2000 watt Pure Sine Inverter.

My solar system is small as I really only count on it to top up the batteries when I’m parked for the day. It keeps the fan and the fridge from draining the battery but with the size of my battery and that I rarely park for more than a couple days the solar system is mostly an emergency backup in case I were to run all my batteries flat accidentally. They are also great for keeping everything running when my ambo is parked and not plugged in.

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