When I first thought about getting a 19′ Airstream and actually living in it for a while, I had no idea how it would go or what to expect. I’ve lived in small homes my whole life and I’ve done a lot of extended trips sleeping in my Jeep and truck, but I’d never RV’d.
Since hitching up my Bambi August 9th, most of the time I’ve spent in it other than a short 3-day weekend boondocking trip was hooked up to full power in my friend’s driveway while finishing the remodel of her guesthouse. Then at the end of August, I jumped right into solar-powered off-grid* living.
I’m still not completely sure what I was thinking but I’ve said that about many things in life. To this day, I haven’t regretted a single one of them. Yet… I should say!
*Yes, I’ve been technically off-grid, powered only by solar, though I’ve had easy access to a septic dump and water as well as hotspot reception for my tech job. So off-grid yes, but maybe comfortably off-grid?
And now here I am, wrapping up 17 days of solar-powered living. It’s kind of incredible. And even better? Life is simple, relaxing, and amazing. I had planned to keep this up a while longer but today I packed up and moved to the local state park to hook up to power. The one thing I hadn’t counted on? Wildfire smoke. Though my solar panels were still charging at a far reduced rate despite the smoke, I really wanted to be able to run my A/C to get some clean air for a few days until this blows out.
Many have asked for some details about my solar setup, so I’ll do my best below to outline what I bought and why, what I’ve learned, and how I’m making it work.
My solar power setup.
Let me first say that if you do any amount of RV solar panel and battery research online your head will start to explode pretty quickly. I’m a good researcher, but electricity and batteries are not my forte. I learned way more than I ever thought I would about voltage, watts, amperage, and solar panels. I feel like I went back to 12th grade science.
Ultimately, I ended up buying a 180-watt Zamp portable solar panel and kept my two completely stock 12V Interstate marine batteries that my Airstream Bambi came with.
Yep, that’s it! I’m running stock wet batteries and a portable solar panel. Nothing crazy and nothing that expensive.
Why a portable Zamp?
There are a lot of reasons I bought a Zamp portable panel, the biggest two being cost and ease. At the end of the day, it felt like a simple way to start without a huge investment. Here are some more details below on why I chose what I did.
Affordability. Airstream quoted me over $4,000 for a 200-watt solar kit with two AGM batteries and nearly $3,000 for just the roof-mounted 200-watt panels. I’m not knocking these prices, dealer installs are notoriously spendy, but I couldn’t justify that kind of money, especially in the midst of a land purchase and home construction project.
My portable 180-watt Zamp solar panel was $750, which I considered a very reasonable investment. I also kept my stock wet batteries, mostly because I’m a fan of using what I have. Until I gain some actual solar living experience and figure out how my batteries perform, I see no reason to upgrade.
My Bambi is Zamp Solar Ready. Newer Airstreams like mine come pre-wired with a “Zamp ready” sidewall port, which is an adapter that the panels plug straight into. It’s plug and play easy.
Yes, you can buy other brands of solar panels and still use this port but it requires some electrical work to reverse polarity. I have enough projects already and don’t want to be an electrician yet. Plug and play sounded easy and it was, so I bought Zamp.
If you do want to geek out on wiring though, here’s an excellent article about how to wire a GoalZero panel to a ZAMP port.
Portability. With a portable panel I can park in the shade and put the panel in the sun, which is a huge win for living in a hot sunny climate like Central Washington. Granted, I only have a 15′ cord, which isn’t that long. I’ll likely buy an extension because it is quite nice to be able to move the panel into the sun.
Locally manufactured. Zamp is based in Bend, Oregon and every panel they manufacture uses mostly locally sourced materials and has a 25-year output warranty. I’m a fan of buying local!
Solar power cliff notes.
Now that I touched on the reasons I bought my Zamp, I figured it might be good to try to distill some of the things I learned over several months of solar panel research. Again, I’m not an expert, I’m a newbie, but a lot of this stuff was news to me when I first started. Here’s what a call “solar power cliff notes for dummies.”
Lesson 1: Solar power does not power your RV, it charges your batteries. That’s right! Solar panels do not power your RV, they only recharge your batteries, which power your RV.
I think this is the biggest lesson I learned while doing my solar power research and it’s an important one because it means that no matter how many solar panels you buy, your power is only as good as your batteries. And no matter how much solar power you have, you’re still on battery power, which for me without an onboard inverter, means no 110V outlets, microwave, or A/C. We’ll come back to that one below….
Lesson 2: Solar power is only as good as your batteries. I could buy all the solar panels in the world but at the end of the day the maximum power I can generate is from my two stock marine batteries because lesson 1, the panel charges the batteries, not the RV. There’s a finite amount of power there.
Lesson 3: There are three main types of commonly used RV batteries. I don’t want to go into a huge detailed analysis of batteries because there are way too many articles out there that already do that, but the most commonly used RV batteries are:
- Flooded or “wet” cell batteries. These are the cheapest, most commonly used, tried and true batteries. However, they require a monthly check on water levels and periodic refilling with distilled water.
- Absorbed Glass Matte (AGM) batteries. The latest and greatest in lead-acid batteries are considered a step up from wet cell batteries because they require no maintenance and are a bit more robust. They’re also slightly more expensive. Lifeline AGMs come highly recommended for solar power.
- Lithium batteries. In a nutshell: very light, very expensive. You can draw down the entire charge of the battery but charging them in a cold climate below freezing temperatures can kill them.
It’s likely that once my wet batteries start to degrade I’ll eventually upgrade to Lifeline AGM batteries. They seem like a good compromise of price and capability. The bottom line though is that no amount of solar panels will help you if you have crappy batteries. So make sure your batteries are healthy!
Lesson 4: Battery depth of charge. Turns out unless you buy really expensive lithium batteries, you can’t actually use 100% of your battery charge if you want your batteries to last. With both wet and AGM batteries, discharging them more than 50% will severely compromise their life span.
A fully charged wet battery will read 12.6V or higher. One 50% discharged the voltage will be around 12.06. Most sources I read recommend that resting voltage should never get much below 12.3V to maintain optimum battery life. Sure, you can discharge your battery deeper if needed, but you’ll be replacing it much sooner.
Most people say to get a “real” battery voltage meter but my Airstream has one that works reasonably well. Granted, the voltage monitor on my Zamp is far more accurate so I often just keep tabs on it through the window.
Ok great, but how much solar power do I need?
That’s the million dollar question, right? How big of a solar panel do you need? How long can you last on solar or battery power before your battery is 50% discharged?
Everything I just talked about above is sort of critical to understanding the whole equation. And so here we go, some math! Ready?
Each of my wet batteries has around 80 amp hours of power, so I have 2 * 80 = 160 amp hours. But…. since I can only use 50% of that, each battery in fact has only 40 amp hours, so ultimately, 2 * 40 amp hours = 80 amp hours.
How much is 80 amp hours? Beats the hell outta me!
No way was I going to sit down and try to calculate my assumed power usage, so instead, I took myself on a long weekend trip to a local forest service road, completely off-grid, to see how long I could last before my batteries dropped to around 12.2V. I figured if my batteries sucked and died, well, it would be a quick trip!
The result? I lasted 3 days!
That means I used about 80 amps of battery power in 3 days, which is roughly 25 amps of power per day. Granted, I’m a pretty low power user. During those 3 days, I ran the ceiling fans, refrigerator (sometimes turning it off at night because it was chilly already), water heater, water pump, radio, and charged my phone via onboard USB outlets. I used my solar lanterns because they’re a softer light than the bright Airstream LEDs. I’m also not a big TV watcher, so I didn’t use it at all.
I was conservative but felt comfortable.
The best way to figure out what size solar panel you need? Take yourself boondocking and see how long you last on battery power. It’s a way more fun way of calculating your energy use. And be honest. Don’t be ultra-conservative, just use what you use. It’ll inform what you really need.
Putting it all together.
All the information above combined with my little boondocking experiment taught me that I use roughly 25-30 amps of power in good conditions, so I started looking at the amp hours generated by Zamp’s different wattage panels. Their largest portable is 230 watts, which costs $950, weighs 47 lbs and can generate a potential of 77 amp hours with a typical 6-hour charging day. Their next size down, the 180-watt solar panel, generated 60 amp hours in optimum conditions, was a tad lighter at 35 lbs, and a tad cheaper at $750.
I thought the 180 was the perfect compromise of price, weight, and potential, so I took the plunge and bought it, having no idea if I guessed right. Would it keep my batteries charged? Would it fail miserable?
The solar results.
Well, as mentioned earlier, I’m now on day 17 of being completely off-grid and I haven’t had a single fail powering everything I need, so I’d say that’s success! I have yet to drop my batteries below 12.2 and in fact, most of the time they’re staying between 12.4-12.7+ volts, which seems to be somewhere around 60-100% charged.
That being said, I’ve had a string of solar perfect blue sky days, I’m in comfortable temps, and I’ve not had to run my furnace for any length of time. I’m in ideal, optimum solar conditions. The panels have been generating anywhere from 30-50 amp hours daily and that’s with being in a location that doesn’t get full day sun. I get prime 12pm-5pm sun and I don’t always babysit my panels and move them around. If I did and had a bigger view of the sky, I could likely get 60+ amps per day here in Central Washington.
But here I am, 17 days of running my refrigerator, ceiling fans, water pump, USB ports, and even the occasional chilly morning furnace warm up and my batteries are fully charged every day!
I’ll admit that if I got a string of maybe 3+ days with poor weather, I’d be in trouble without a generator, but in these conditions the panels are rocking. Even with all this crazy thick smoke that blew in, I’m still generating 15-20 amp hours of power, which is about 50% of normal but still a little unbelievable. I fully expected 0.
More specs on my Zamp panel and installation.
As mentioned earlier, Zamp is based in Bend and they make a variety of solar charging kits, accessories, and panels. Their portable panels range in wattage from 45 to 230 and come with weather-resistant 5-stage charge controllers. You don’t have to worry about weather with Zamp panels.
I only had to unpack my panel, open it, plug into my Zamp port, then select the proper type of battery on the controller display. Zamp‘s 5-stage charge controllers keep your battery from frying, so it’s important that you select the right type of battery that you’re charging. The controller has 5 battery settings: LiFePO4, LTO (Lithium Titanium Oxide ), Gel, AGM, Conventional lead-acid (WET) and Calcium Batteries.
Voila! It really was that simple.
The charge controller tells you your current battery condition (75%, 50%, 25%) as well as charging status, the voltage and amperage going to your batteries, and the total amp hours you’ve generated in the last 24 hours. I love this last setting! In fact, I kept running outside every 20 minutes when I first hooked up my panels to see how much solar I was generating. It really was that exciting!
If you don’t have a Zamp-ready port on your RV, the panels come with alligator clips that clip easily to your batteries.
And now finally, how about some solar Q&A? Here are some questions I’ve fielded from friends over the last few weeks.
Q: Do you have A/C?
A: Yes, but not on solar power. A/C is a power hog and doesn’t run on batteries so I don’t have it on solar. Only on shore power. With the thick wildfire smoke we started experiencing over the weekend, I actually headed to the local State Park today for shore power so I can run my A/C and get a break from the smoke.
Q: Does your microwave work?
A: Not on solar power. This is another power hog that doesn’t work on batteries. I use my propane cooktop exclusively while on solar.
Q: How are you charging your laptop without 110V shore power outlets?
A: Ok, this one is more complex. I realized pretty quickly that my Airstream didn’t come with an inverter, which is a device that turns your 12V battery power into 110V. Basically, it lets you plug in “normal” appliances, like laptop chargers, coffee makers, things like that. Most Airstreams have one but Bambis don’t.
I work a tech job during the day, so it’s pretty imperative that I can keep my MacBook, Surface, phone and hotspot charged. The solution? Portable inverters!
You can find lots of wattage inverters online that plug into the cigarette lighter adapter of your vehicle. I already have a 300W for my truck. My Bambi has a 12V cigarette lighter type TV plugin, so I bought an additional 100W inverter from the local Ace Hardware for $35 that can plug into that and charge off my RV batteries.
A word of caution though: an inverter will draw a lot more amperage and can drain your batteries fast. I only use it when my batteries are well charged or when my solar panel is cranking maximum power to my batteries.
The primary way I keep my laptops charged? I have two portable NinjaBatts that I usually charge off a separate portable 100W solar panel. I can also charge the NinjaBatts from my the built-in inverter in my Tacoma truck bed.
I power my laptop off my portables rather than my RV batteries. I’ve also successfully been able to charge my NinjaBatts off my little 100W Ace Hardware inverter without negative consequence to the RV batteries, but again, I do it during the day when I have full sun and the solar panels are cranking. I prefer to keep my RV batteries for the essentials like the water pump and refrigerator. My phone and hotspot stay easily charged off the onboard USB plugs in my Bambi with no problem.
Q: What appliances and powered devices are you frequently using?
A: Other than the electronics I need for a work, I’m not a big power user. I watch little TV and tend to use my solar lights over onboard LED lights. I’d say the most common things I’m powering are:
- water pump
- ceiling fans
- onboard USB ports for phone and hotspot and other devices
- USB-powered LED dragonfly string lights, pretty much a must-have!
- LED onboard lights, but I primarily use my solar lanterns
- the Airstream also has some parasitic draw with the propane/carbon monoxide detector
As I mentioned earlier, I power my laptop mostly off my portable GoalZero and my truck. I’ve used the furnace briefly on a few chilly mornings, which uses power for the blower. I’ve also used the water heater a handful of times, which is mostly propane, but still a bit of power.
Q: How do you power your cook stove?
A: My two burner cookstove is propane. No battery power required!
Q: What are you doing for coffee?
A: Coffee is non-negotiable for me and I like my fresh ground beans! I have a little Cuisinart two cup coffee maker, but it only works on shore power, so I got myself a little hand grinder and fancy pour over. The grinder is fantastic and doesn’t take very long. I call it zero amp coffee.
Q: What’s the biggest power drain for solar?
A: Without question the refrigerator. I was able to run the refrigerator for 3 days on battery power without solar, so it’s reasonably efficient, but it does burn the most power. I keep it on the lowest setting and if it’s chilly at night, I’ll turn it off completely until morning to save power. It stays plenty cold.
I think perhaps the 2nd biggest draw is the furnace. It uses propane for heat but the blower fans use battery power and seems to draw a decent amount of power.
And now the last question, which isn’t necessarily related to solar, but is one of the biggest lessons I’ve learned while off-grid living.
Q: What’s your shower situation and what’s your biggest surprise of off-grid living?
The key to off-grid living isn’t power management, it’s water management.
I’m cheating a bit when it comes to showering. I’ve taken some quick Airstream showers, but mostly I’ve been using a nearby shower to cut down on my waste water, which leads me to the point above. I spent so much time researching power and solar that I overlooked the biggest limiting factor when living off-grid. It’s not power, it’s water and waste management!
Yep. Managing your fresh water and waste water is really the key to how long you can stay off the grid.
My Bambi has a 23 gallon fresh water tank, a 28 gallon gray tank (for sink and shower water), and an 18 gallon black tank (for, well…. you know). They’re not huge, but they’re decent sized. And it’s only me. But it was eye-opening how quickly I can fill the gray tank. In my first two days my gray tank was already 30%.
I got a lot more aware and clever with my water usage, mostly when it came to dish washing and eventually I was able to make it 10 days before my tanks were around the 65-75% level. I think I could survive 2 weeks on my tanks before needing to dump them, but it takes some real awareness and periodic access to outside facilities.
As far as fresh water? With all this warm weather and both myself and my dog being pretty athletic, we can easily run through my 23 gallon tank in a matter of 5-6 days, so having access to water is important too.
If you’re thinking of solar power and off-grid time in your RV, take some time to get really savvy with water and waste management. It’ll be the biggest limiter to how long you can stay out.
Final thoughts on solar-powered living.
It’s been pretty awesome spending the last 17 days completely under solar power. It’s been a simple, enjoyable life that has made me even more keenly aware of my footprint and power usage on this planet. It definitely makes me appreciate the little things, like a microwave Mac ‘n Cheese dinner and fresh air!
If you’ve ever thought about going solar, do it! Start small, it doesn’t take a huge investment. Get a portable panel, hook it up to your batteries, and try it out. It’s pretty fun to get out, harness the sun’s power, and not be dependent on loud generators. It’ll give you a new appreciation for simplicity and the things you sometimes take for granted. Just remember that at the end of the day, your power is only as good as the batteries that store it and you’ll likely run out of water or fill up your tanks way before you run out of power.