So I mention quite frequently that when I boondock, which is over 90% of the time these days, I live on 100 watts of solar. The next question asked is usually: “What can you do with 100 watts of solar?” So today I thought I’d answer that.
Why 100 Watts
First it’s probably important to bring up why I chose the solar solution that I did. In the RVing world, 100 watts for full-timing is considered the bare minimum. Most rigs, even small Casita-sized rigs and vans, choose to have more. So why 100 watts?
- Cost. My 100 watt portable suitcase was only $250, that’s about as cheap as you can go for a kit that requires no do-it-yourself work.
- Simplicity. There’s very little work involved with my setup. It’s just two 50 watt panels with a hinge in between. It’s easy to set up, simple to store in the back of the truck when not in use, and required no messing around on my roof.
- Portability. The panels can be set in the sun even if the trailer is in the shade, and I can park my trailer facing any cardinal direction and still get maximum use of my solar by moving it where necessary. It also means when I switch to my teardrop (which yes, is still happening – just not until September as I’ve been saying from the start), I’ll be able to keep my solar.
- Battery restrictions. Casitas have a small battery compartment that can only fit a single Group 27 battery. There’s not a compelling reason to have more than 100 watts for a battery of that size. Yes, I could pay to have modifications done to the Casita to have a second battery mounted elsewhere and then it would make sense to have more solar power, but I’m switching rigs soon remember and what I have now meets my needs.
It’s also important to note that as a solo RVer, I use less power. So having 100 watts for me is like 200 watts for a couple.
What 100 Watts Powers
I don’t pretend to be an electrical expert, you can find articles and videos online from people who are much more knowledgeable about 12-volt power than I. A good starting resource is The 12 Volt Side of Life by Mark Nemeth, which starts with the basics of the RV 12-volt system in part 1, and then in part 2 dives into the technical aspects of how much power various appliances draw, getting specific about how long you can run various devices in an RV based on how much power you have.
That’s all beyond me. Fortunately, you do not need to be an electrician to make use of solar power. The most important thing to know when it comes to usage is that letting your battery/batteries get below 50% charge will damage them over time. So as long as you have some sort of monitor (I use a simple voltmeter) you can check the state of your batteries and make sure they don’t get too low. Over time, you’ll get a feel for how much power you have through trial and error without having to calculate the fancy math.
With that said, here’s what I use with my 100 watts:
- Fridge. I run my fridge on propane when boondocking, but like most newer RV fridges, the propane setting still uses a small amount of power to start up.
- Water pump. Using running water (washing dishes, flushing the toilet) takes electricity. I don’t shower in my RV and use a minimum amount of water for dishes, so I don’t use my water pump as much as some RVers do.
- LED lights. Replacing the default light bulbs in your RV with LED versions reduces power consumption drastically. I can keep one of my overhead LED lights on all evening without worrying about running the battery too low.
- 12V fan. I have a Fantastic Fan mounted in the roof of the Casita, and on hot days I may run it in the afternoon.
- Charging electronics. This is what consumes the most electricity for me. I’m on my laptop at least a few hours a day most days for work – I don’t have Netflix or watch much YouTube. I also charge my smartphone once or twice a day. Less frequently I also charge my Kindle, and other assorted devices. I do not have a TV, which can also be an electricity hog.
If this list seems pretty short, that’s because it is. I have a water heater, and starting that up would also use electricity like the fridge… if I ever used it, which I don’t. My approach to RVing is quite minimalistic and my main forms of entertainment use little, if any, electricity. Not everyone would be happy with only 100 watts of solar, but it’s worked well for me.
Getting the Most of a Small Wattage System
When you have a small solar setup, every last drop of power counts. Here are a couple things you can do to get the most out of a small wattage system:
- Tilt your panel towards the sun. It makes a huge difference in the amount of power you bring in, especially in the winter months when the sun is at such an angle. If your panel is portable, you’ll also want to turn it to face the sun from east, to south, to west throughout the day.
- Keep the panel clear of shadows and debris. Even a shadow over one small part of a panel leads to a drastic reduction in efficiency, so park/place the panel so that you don’t get shadows. Wipe it down regularly to get the dust off.
- Charge your devices during the day when the sun is high and you’re bringing in power. It’s easier on the system that charging things at night and letting the battery get low.
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