Off Grid Solar Powered RV Air Conditioning – Is it Possible?
Since we shared our very first RV solar video we’ve been asked the same question over and over: Can I run my air conditioner with all that solar power?
We’ve always responded with a “NO” since we felt it wasn’t realistic based on the battery banks and inverters we’ve had in our previous motorhomes. With our current RV, we installed some serious Off-the-Grid technology and for the past several months we kept thinking, maybe we can run our a/c without being plugged in?!?
An opportunity landed in our laps as we unexpectedly crossed paths with our friends John and Peter The RV Geeks near Joshua Tree National Park. It’s almost like the stars aligned: The Geeks are RV DIY install gurus, the desert temps were rising, the sun was brightly shining and the wind was calm so we could actually talk to the camera.
So, we decided to put the question to the test! Will we really be able to run our RV air conditioner off our solar setup? Let’s find out!
Please remember we’re not RV Solar or Air Conditioner professionals. We’re simply sharing our experiences and I’ve done my best to explain our test results and I hope the information below makes sense.
Oh yea, and don’t forget the most important part of this equation: We’re only discussing running 1 A/C unit in full sun. If your RV so large you have to run 2 or 3 A/C units to effectively cool it, or you wish to park the RV in the shade, well…I think you’ll need to tow a trailer full of solar, battery and inverters to handle it. Or you could just run the generator or plug-in to shore power and say “fahgettaboudit”.
The missing link for us is the Soft Start. After making this video the Micro Air people decided to offer a $25 discount coupon if you use the code “GWTW” at checkout. We think that’s pretty nice so we’ve passed it along to you: www.gonewiththewynns.com/product/air-conditioning-off-grid
What do you think? Any plans to install a giant off the grid kit to run your air conditioner? Think we’re crazy for even suggesting it? Share your thoughts and questions in the comments below because I know you’ve got an opinion on this RV mod.
Disclaimer – This video and post are solely based on our testing experience. We were not sponsored by or swayed by the mfrs of these items. The soft start discount was offered by Micro Air after we created this video, we receive a small commission and you get a discount so we think everyone wins.
A 100 amp draw on 12vdc is 1200 watts.
1200 watts on ac @120vac is 10amps (not counting for power factor)
The formula is volt time amps = wattts
You can also divide watt by volts to get amps.
Something to always consider when wiring yoir 2000 watt inverter, is that it will be capable of running 360 amps!
So pock a very heavy duty wire for this connection!!!
Because yoir inverter runs 200p watts full time it is rated to run 4000 watts peak!
This is how rvs burn!
Not sure if you’ve covered this somewhere else, but they make heat pumps (air conditioner/heater) units that work on an RV or in your home. They use a lot less electricity than an air conditioner and can be fitted to a sail boat. Here’s the link to one on Amazon. http://alturl.com/vge24
One of my main questions is. How many hours can you run this on and do you have to plug in your generator at night. Please let me know
The question of how long it can run depends on how low you have the AC set and how big your battery bank is (and what kind of batteries you have). The generator runs off the gas in the coach, so it never gets plugged in. Hope that helps!
Depends on the specifications of the unit you want to run.
In most cases, a 10 KW would run roughly a 2 ton maybe 2 1/2 ton a/c.
Looking at a 10 KW portable, price is pretty close to an 11 KW home stand by with a 200 amp transfer switch.
Then you’ll have load management capabilities already built in and no worries about gas and all the other stuff associated with portables.
5/18/2019 Appreciate this site– very informative and much to consider!
Really interesting article and I enjoyed watching the video.
I’m starting to rethink the Solar concept now. When we purchased our RV, the dealer told us that it’s Solar Ready, but what’s on the market is junk. But I think i may have to give it a try now.
Yeah solar power air conditioner is efficient to cool the house while saving the scare resources.
Ok not sure what ac y’all have but the one in my camper is on a 20amp beaker so the one in mine can’t be more then 18 amps
Thanks so much for this video, I used your tips on my setup. One thing I can’t figure out though is your Mach 15 was drawing about 75A from the batteries (has a rated draw of 14.8A on AC power). I just completed the install of a Mach 3 Power Saver unit and it is drawing 100A from the batteries even though it’s rated draw is substantially lower at 10A on AC power). I’d figure that my power draw would be about 1/3 lower than yours based on the specs… any idea what might be different or what I’m missing? Hoping to improve my power consumption, thanks for your help!
Setup is 400Ah lithium, 500w solar on the roof (will add another 500 soon), Magnum 2000w inverter/charger, Mach 3 Power Saver with Easy Start installed.
Voltage X amperage = voltage
Sorry voltage X amperage=wattage
Bruce B Orr
Bryan, that is interesting. I am seeing similar results with my set up and wondered if you figured it out. I have a Mach 3 PS which I expected to draw 10A (120V) but I am observing a draw of about 14A (120V) at the breaker. My only guess is that the 10A is compressor and the 4A is fan.
This was very interesting and I enjoyed watching. You guys are adorable – just keep it at the level of this video and it will never be overboard. At my present income and expenses I would not be able to afford this solar set up much less the RV itself. But I think I can afford a used camper and add A.C. to it. Thanks for the inspiration.
douglas and donna
we are new rv owners and would lie to know if it is goind to coast and arm and a leg to go to solar power
If you head to the RV page and click on the “RV solar” tab [ https://www.gonewiththewynns.com/rvin ] you can find details & costs for a couple of different setups. Solar nay-sayers will argue that you can never recoup the cost of a solar setup (it will take years of off-grid free camping to do so) but solar fans will tell you that’s not the point: living off-grid in beautiful, quiet places and not having to run a generator all the time is really the point. Quality of life is worth the cost. The first thing to do is to determine how much solar you would need. If you prefer to spend lots of time camping in parks with hook-ups and only do a little boondocking, it may not be worth it. Someone living in a Casita trailer may get by just fine with a single portable panel. If you’re in a big rig with a residential fridge, your needs will be quite different. If you’re seriously thinking of getting solar, my recommendation would be to invest in a battery monitor (there’s a post on those on that solar page link) so that you can determine how much power you’re using. If you prefer, you could also go to someone who installs RV solar and pay for an energy audit to get that info.
How did you guys choose your inverter? It seems yours is $2200 on Amazon but other inverters with same specs are $400. Am I missing something?
Great video. Attempting to put 1000 watts of solar on my RV to never use the generator again…..Hopefully!
Are they all pure sine inverters (like ours) or are the cheaper ones modified sine wave? Modified sine wave inverters don’t always play nice with electronics and can fry a lot of gadgets, and there’s no way to tell beforehand if most devices are incompatible or not.
I run everything in my camper including 15,000 btu AC unit with 1,800 watts solar array ,500 watt rated wind turbine 1,200 watts usually, 1410 AH 12v battery bank, 6kw inverter 12kw max. I turn on our AC unit and it runs till dark batteries are full. Its awesome
I tow my own power system on a trailer behind my camper.
How much weight did this system add to ur rv?
Jason / Nikki
During the AC solar test what would the result be if you did the opposite and were pumping in 80 amps of power while continuously pulling out 55 amps of power?
Have fun! stay safe!
Thank you for testing this out?
My only question, Is this an entirely separate battery system/bank from the ReLION batteries you use to power the rest of your vehicle?
If so, can both systems be combined?
Thanks for again sharing!! Your site is an AMAZING resource!
Thank you for testing this out!!*
Hi Great videos,What about a evap? can not spell it.In Arizona we call them swampbox? ir runs a pump and fan lot less amps.They fo no work well when it is humid.Ever looked in to it? take care.sorry about all the bad spelling…Dominic…
Will you be updating this article for your boat? I thought I saw that it has A/C in one of the videos. Obviously that it meant for shore power but with enough panels and batteries and a soft start I would assume it is doable. Do you have to ability to a/C only the master stateroom?
We are working on this for the boat and yes there will be an update! Stay tuned…its going to be a good one!
Thanks for your thorough research. I had the same question about running the a/c off grid. However I can’t see putting that much money into it for the few times I would need it. But I am sure others would use it more than me. I am converting a school bus to a camper. I love doing the work myself and love learning more about what can be done with them. Slowly I am getting it the way I want it. Been at it for a little over a year so far. Have been able to use it after the first three months of work. Now it’s mostly just upgrading and customizing. Keep up the good work. Happy trails.
Nice. You guys are a fun mix of enthusiasm, practicality and even the necessary technical details. Kind of you to share your test. All the best…
James Marvin Cook
The wife and I are working on turning our RV in to an off the grid full timer machine on wheels. with pretty much the same set up you guys hard. My quest tho is with the soft start. Did you yourself install a soft start, and if so can we get a quick picture of where it installs and what it looks like? Thanks, James.
The soft start is from Micro Air. They have offered a discount code but I will have to get back with you on it. It is something you can install yourself if you’re comfortable with wiring.
James M Cook
Thank you, I look forward to hearing from you.
I just received the code: GWTW
Type “GWTW” into the discount spot at checkout. I believe it’s good for $50 off. If you have any questions on install the Mfr is very good with helping.
I’ll update the post once I have all the details, they just sent me the info today.
Matteo Giovanetti from Micro-Air, Inc.
We at Micro-Air are thrilled with the response from everyone on the EasyStart, and we greatly appreciate the Wynn’s. To show our appreciation, we’ve just produced and posted a YouTube video showing the actual installation into an RV rooftop A/C system. There are links to this video now set up from the EasyStart product page (click on my name above). Stay tuned for more as well since the Wynn’s and we worked together to film the EasyStart installation into their marine A/C systems aboard their new boat!
Love your show, your positive attitude and vast amount of imput you guys put out from your experiences. Can’t wait for your next catamaran adventure.. 🙂
Wow… just, wow. I’m setting up to full time with my rescue dog Dixie and was worried about heat. Like you I can’t believe no one has packaged and marketed this idea as an end-to-end solution already. I’ve been haunting forums and reading PDFs until my eyes bleed and thought for sure there was just no way I could “boondock” and keep a trailer at a reasonable temperature without that constant generator in the background. Thank you SO much for sharing this invaluable information.
Hi Nikki & Jason. First of all: You do a great job! Thank you for all of your nice videos and info. My question: Why do you need so much solar power on your roof (ok, for running your ac-system I understand, but as you don’t recommend it…)? What kind of appliances do you normally use during wild camping? We have 300W (2 thin and flexible 150W panels) on our roof combined with batteries (total 1960 Ah) and a 3000W pure-sine-inverter. This is good for almost everything we need during wild camping. Besides the fridge we run and a Coffee-Machine (Typ Jura ENA 9; 10 amps / 1450W) in the morning (no problem to run the coffee-machine two times consecutive, even at 4AM), a hair dryer, as well as some smaller devices like the fantastic fans (we never use the ac), electric tooth-brush, a 4G LTE router, laptops and sometimes, when the weather is bad, a dvd on the TV-screen. Our limit of wild camping without moving is set by the water-tanks and not by the electric power (ok, and the weather…). Up to 5 days it’s no problem as well as 5 days on a Ferry (only the fridge runs). The costs: $900 for the panel-kit, $2000 for the batteries, 1000$ for the inverter (replacing a 2000W inverter) and some $ for additional things like seal, screws, beer, steaks, charcoal, etc.. Installation-time 3hrs (self-made). Your costs?
Just as a remark: If you rise your fuel consumption too much due all your solar-stuff on the roof (air resistance and weight) you’d better run the generator for saving energy…
By the way: If you really need an air-conditioner out at the pure nature and wilderness, you should install a DC-air-conditioning-system and fridge, etc. So you won’t lose power on the inverter. You find such nice things on http://www.geinnovations.net.
A typical recommendation from any solar provider is 1 amp hour of battery to 1 watt of solar. For living and working full time from an RV, Tiny House, Sailboat, etc we’ve found that 1000ah of battery and 1200 watts of solar to match is a good start. To each their own, we know people that never use their plugs and are happy with 100ah of battery and a 120 portable panel just to charge their phone and tablet.
You just need to get rid of the inverters
Nice. I did not know about the soft start. I was thinking a way around that is to just run the engine or generator to start the a/c and then run off the inverter after the initial start up energy surge.
I don’t know if you guys keep of the comments on “older” posts but if you do I have a question. When I first read the article I didn’t think of all the implications. Have you tried running a roof air conditioner while driving so that it is mostly powered by the engine alternator? The F-53 chassis has a 160 amp alternator. A lot of our generator time on our Tiffin Allegro has been while driving when we have extra people with us who are watching TV or lying down in the bedroom. It seems like with the hybrid inverter that you could run one AC using mostly alternator output. I can’t think of any reason it wouldn’t work. When it is just my wife and myself we can get by on the dash AC but since we start and finish up our travels in central Texas we spend a lot of time in warmer climes and so we sometimes run the generator even when it’s just us aboard. Now I am even more excited than when I first read the article.
Have you considered looking for a boat in Canada?
Im not the seller but I do follow your exploits so when I saw thus, I thought about you two.
We are looking all over the world and there are very few 🙁
Truly well done!!!! I am a sailor so I look forward to your change to the boating world!
A swamp cooler, AKA Turbokool would have been a better item to test and has worked in the deserts for decades.
Only draws only 4.6 amps per hr, and can run off a 12 battery & one solar panel.
We have had swamp coolers living in Arizona and they cool the house 30 degree.
Yes, but a swamp cooler only works in a dry desert and not so much in the rest of the world.
My 50 years using swamp coolers from the ultra deep deserts to Florida swamps, unless you have a 100% humidity rate during a Florida monsoon, it will work a whole better than nothing when u have no hookups or stress your RV power system running an a/c unit. Solar a/c just isn’t worth the expense, or the potential equipment damage even with step downs & the like.
om using your link?
Hi Nikki: Absolutely LOVE you and your husbands production; light hearted, informative and more enjoyable to watch than most tv programs! Quick question on Joe Calise comment. Maybe it would be beneficial to use both systems so that the power draw on the air conditioner would be less? And, when I click on the links y’all have provided above to like Amazon, do y’all get credit if we purchase an item from using that link? Blessings, Arnon
I don’t mean to step on anyone’s toes here, but let’s lay out the facts of swamp cooler usage. And this also comes from experience working on them with several companies locally and also with speaking with a MasterCool specialist. I’ve lived in Tucson, AZ for over 30 years. Swamp coolers do work when humidity is low. Once humidity gets up to around 40% or higher they do not work very well, unless you like living in a hot, humid environment. Whatever the humidity level, a swamp cooler will add even more moisture to the air. They work by evaporative cooling. So, yes, when AZ has humidity levels of 10-30% or so, SCs work. When humidity gets higher they don’t work. If you think they do, for those that don’t know, think of living in the southeastern states with +95°F days and 90% humidity. Yuck!
Swamp coolers require an open window to vent the positive pressure from the cooler fan.
The other issues with swamp coolers:
1.) They use a LOT of water. So there goes your drinking, cooking, cleaning water supply.
2.) They will dump a tremendous amount of moisture into you RV or tiny home. My wife and I have experienced mold issues in every swamp-cooled house we’ve lived in. I never had issues with humidity induced mold issues when I lived in Upstate NY for over 26 years, a place that gets a lot of precipitation. Yet here in the AZ desert: swamp cooler = mold. Do you really want to dump all that water into your RV?
3.) Swamp coolers are large. They have to be in order to work. Do you want some large 8 cubic foot monstrosity sticking up off the top of you RV?
4.) Swamp coolers break down readily, i.e spring leaks. So, introduce water constantly dripping off your roof or leaking into your RV.
5.) Mosquitoes love swamp coolers. Sure you can add various things to the water but that also will blow into your RV. Some people believe mosquitoes can’t get into a SC. Almost every SC I’ve opened up to work on had a swarm of mosquitoes. Which then get blown into your living space.
6.) Every time you move your RV to a new spot and reset up, you will have to pre-wet the pads in the swamp cooler. The best way to pre-soak cooler pads is with a garden hose. So, more water usage.
7.) No matter what type of swamp cooler pads you use, if they are not used constantly, i.e. kept wet, the pads grow bacteria and develop nasty odors, which blows into your home.
8.) If the pads get dry spots on them while in use, it greatly reduces the effectiveness of the cooler.
Swamp coolers work for limited situations, like cooling an open faced work shed. Other than that it is ancient technology that creates more issues than it solves. My wife and I have had high quality boots and clothing ruined by swamp coolers. Arizona: arid desert country with super-low water tables and about ten inches of precipitation per year. Yeah, good idea to use swamp coolers here, NOT.
In conclusion: RV + Swamp-cooler = not good!
If you cannot afford ac in an RV and all the electrical to make it work:
Travel with the weather. Use shade whenever possible. Create a tropical roof that pops up about a foot over the top of your RV if there is no shade. Use shading canopies on all sides of your RV, the full length of you RV, not just over windows. Use fans to circulate air. Physically adapt to your environment. Sorry this got so long, lol. Hope it helps someone.
Nice summary! I didn’t know about the mosquitoes – yuck.
i looked at this site and found them to be not just fairly priced but outrageously priced for what is basically a home made humidifier, something you really don’t want in an RV. That’s the beauty of modern AC units they remove humidity making the air dry inside the RV. You can buy a 5000 BTU AC unit which can run off very low power for 112.00 at Walmart, If you are the one selling these Joe this is considered spamming. I have made a similar device which you fill a cooler with ice and it runs thru a sealed system with a radiator pumping the cool air into the room, condensation builds on the radiator but is drained out not put into the air. It works very well but the ice doesn’t last more than a couple hours. So basically not worth the hassle when you have r-14 systems and an abundance of free electricity. Ever see what high humidity does to a woman’s hair? LOL
And you have how much experience with swamp coolers exactly because you never clearly stated? As far as so called spamming since you did make the accusation againste for my long time experince, anyone recommending a particular item is considered spamming? If that is the case, then I’d say the entire web page is such. I think your out of line with your dart throwing as well as blanket analysis in a topic you appear to have no background in. But in this day and age the internet gives any critic with an ax to grind and a keyboard, a degree in trolling.
I too find Illya that you have a degree in trolling as stated earlier. One’s mention of a particular product doesn’t warrant attacks for so called spamming. Otherwise this entire webpage would be considered as such. I think Joe’s experience is worthy praise and consideration as most of us have no such experience to draw from. The observations provide another point of view to draw from considering MOST RV’ers don’t have a lot of funds to use to experiment and proven devices prove more suited that new experiments. Personally, I think over time you will find the a/c on solar will be more costly than it is worth until a system is designed from scratch as such and proves it’s salt over time. Thanks to Nikki & Jason for their blogs and those who make worth while contributions. As for the rest, keep your untried opinions to yourself ie: Illya.
We did touch on the Turbokool in our Burning Man Post: https://www.gonewiththewynns.com/keep-cool-extreme-heat-ideas-burning-man
RV’s come standard with Roof A/C units hence why we tested the factory installed item. If we were building a new RV from scratch we may have considered the TurboKool.
My personal opinion is water comes at a premium while dry camping and a swamp cooler uses quite a bit of it, so it too has its benefits and disadvantages.
With the correct setup there is ZERO issue with running the roof A/C off the batteries and inverter.
om using your link?
As usual Jason, you are on top of your game, which we sooooo appreciate!!!
Thank you for this experiment! And the article. I sent it over to my solar guy in NJ and at the end of April we are going to work on crafting a permanent solution for this — he also has been experimenting with a solar specific roof AC I’m really excited to play with this some more – we will let you know how it goes!
Does your fridge already have an easy start or would the easy start be beneficial for it’s operation as well?
I too have thought of this, but the power surge is only 20 something amps, so a soft start may not be worth the price.
Buy RV Lights
Thanks for sharing this wonderful post! This will be real cool if solar power can be used to run AC’s. These wonderful tips will really help for a great RV experience and a new innovation.
very informative! Thanks!
So as I add up your equipment, not counting install, you have about $8000 invested in solar including panels,controller, converter, and batteries. Is that about right?
That sounds about right. We have pricing listed here: http://www.gonewiththewynns.com/rv-modifications-technology
Remember it’s not just for the AC, we installed all this gear for various reasons, the fact that we can run an AC for a couple hours is just a bonus!
I love these super techy geeky videos! I am such a geek at heart and I love all the technical and in-depth thorough discussion. Your videos are great and all the little extras make them entertaining to watch, whether it’s your cat making a “death leap” across the door way or making lemonade while telling us about surge ratings. Good stuff! Thanks for being so COOL 🙂
Thanks Adam, I too love neat tech but I try not to dive in too deep 🙂
Hey, guys….I am a newbie to our blogs and just wanted to say how much I have enjoyed them. I have been a full timer for about 15 years in my 2000 Fleetwood Discovery 37V. Your article on operating A/C with solar power is excellent. My question: where is your gold mine located? GPS coordinates, please. Seriously, the article is excellent and for those with the funds to support it will certainly benefit. There have been so many advantageous improvements in the new coaches over the last 15 years. I agree that exterior design has not changed much and they all look pretty much the same, but the user friendly features are constantly evolving. I look forward to reading and sharing your experiences. Keep up the good work and happy trails. .
thanks. No gold mine or rich parents here, just hard work. check out our make money and travel section (under blog in the menu) where you can learn about what we do and how others make it work too.
om using your link?
You guys are incredible to share that type of info for others to profit from. Blessings to y’all
Reed and Elaine
We have been successful in running a/c (Dometic 15.5 BTU which requires about 2 kW) off combination of solar and battery for about three years. We can do this for 3 to 4 hours in full sun. Currently on beach in Yucatan and have coconut palm shad till about 11 or so that we cannot get a full day’s harvest.
We have 1.4 KW of solar panels. The six panels are set to provide 90 V to TriStar 45 amp which converts to 48 V for the batteryl suite which is a 9 kW-hr LFP system of CALB (Chinese Aviation Lithium Batteries) cells set in four battery boxes of 4 cells each. The 48 V normally goes through a Mean Well 508 W 48 V to 12 V converter. This died in early January. Fortunately, our son who designed and fabricated the system was with us along with his family. He merely set the system to run inverter to original converter of the 5th wheel.. This does have a 60 W parasetic draw. We are currently on beach in Yucatan and will have things fixed in April when we return to US.
Reed and Elaine
That kit sounds AWESOME! We too are about to upgrade our lithium bank and solar when we purchase the sailboat! We’re gonna need A/C the further south we go.
In my Tiny House on Wheels we are installing the 10kw Tesla Powerwall System. For the AC/heat we’re using a 48 volt unit that can cool and heat 600 square feet.
Awesome! Sounds like its going to be a killer setup.
Wonderful article!!! Just wanted to let you know that I’ve tried to find the EC-30W AGS that you reference above and finally called Onan and I was told the that 30W is no longer available. The hard wired WC-30 is still in their inventory and is not as plug and play as the 30W. Perhaps they sourced the AGS product from some other supplier like Magnum or Xantrex, but the product doesn’t look like those produced by the two companies mentioned. If you have additional knowledge relating to AGS or other recommended model/brands we would be most appreciative.
When I spoke with them last the EC-30w was available but they were working on an upgrade…so maybe they’re about to launch the newest product!?! I sure hope so because the AGS from Magnum was a pain in the butt to install on our rig.
Great video! I have only one question or comment…When running the A/C off the batteries, about half the power required came from the solar cells and about half from the battery bank. If you were to run A/C most of the afternoon (assuming that would be the hot part of the day) you would be pulling down the batteries at a time when all that solar would normally be used to charge them. Would you not be heading into the high electrical load part of the day, the night time hours, with low state of charge? I guess if you had sufficient battery capacity you could get thru the night OK but only if you have the ability to replace those amps in the morning before the next A/C usage, would this concept work on a daily or prolonged basis. Am I thinking this through properly? Or did I miss something?
This is why we mentioned adding another panel or two, or using the PowerSaver model A/C unit. Either of these would give us a net zero draw.
Great test, its now solved another task for us, have you tried to run your washer /dryer off the inverter ,if yes and successful what manufacturer is your machine
We have not, but it should work. The only thing is we’d run out of water too quickly. We have the Splendide: https://www.gonewiththewynns.com/easy-rv-laundry
Why did you choose 12 v vs 24 v or 36, 48 v solar system? You can never have enough solar, now that you can easily pay >$1 a watt for panels now! And since you already have system in place, you wouldn’t pay double on panel cost markup…Can you put a price on Independents? How efficient is your ac unit, it was built to run on direct AC voltage. Here is a LG unit LAU090HYV1 or LAN090HYV1 9,000 cu, 15.7 EER, 27.5 SEER, 12 hspf, 563.1 kW (annual), $61 (annual) $737 (life) 45% saving over fed min
There are companies that make AC units to run directly on solar power…
RVs are setup as 12v, thats why.
Great post. You two really set the standard for informative fun and well edited videos. In my RV I have two 4000 watt inverters (24V) and they each start a rooftop AC with ease … As you guys have demonstrated this could work well especially when you have full sun, since you are only about 40 amps short (40*14.1= 564 watts) you could add a couple more panels and the batteries could help with inrush, LRA (although the soft start tech is super cool — this technology has been used in industry for many years and is well proven) and startup. Then you could add a basic PLC and have the system just run the AC when you are net 0 to maybe 15 amp draw — this would allow your excess solar to cool your coach and not impact your batteries for the balance of the day and the night … Just a thought …
As you guys head across to Florida I would be happy to have you guys drop in … I have a couple 50 amp hookups and water sewer — plus gig internet (I’m in the fiber optic business) … Plus i have shop and could help Jason with any updates or repairs he needs to complete prior to you turning your coach in — reminds me of when i was in college and had to clean my apartment to get my security deposit back lol ..
I dont know if i could watch another video of jason cutting wood with the wrong tool or using a fix a flat on a tire with 110+ pounds of air — although i loved ever min of it …. you guys are great — i am about 90 miles north of Atlanta .. i assume that you can get my email from this post if you are interested …
safe travels and good luck with the sailing adventure
Thanks so much for the offer David! We are currently at the factory service center in Alvarado, TX getting the big repairs done and we’re heading east on I-20 this evening. Sadly we’re driving almost non-stop to try and get to FL to begin the boat shopping process as it could take months to locate a “perfect” boat.
You were running 27A @ 13.9V before turning on the Air Conditioner, or 375.3 Watts. After starting the Air Conditioner, the inverter showed 76A @ 13.5V or 1026 Watts. 650 Watts seems low for a standard Camper type Air Conditioner. The smallest Coleman-Mach (the cub) is rated 1270 Watts while running.
That is definitely a Magnum question, I’m not sure exactly what the readouts display on our Remote all I know is it shows the power coming in and the power going out.
Full Disclosure: we build Hybrid Solar Energy systems for RVs. They combine solar, energy management, energy storage and an auto-start generator. Even the smallest allow operation of standard RV air conditioners.
Excellent job doing this, I’m sure there are 1000’s of forum math geniuses who’s blood is just boiling because it really is just simple math and calculating what it takes. I really like to see the lets just try it though and see the outcome. I like the idea of a smaller AC unit to keep an area cool, you can only be in one place at a time right? oh here come the physics of light and protons everywhere at once theorists lol.
If 2 15,000 BTU AC units are required to keep the RV cool, I would say insulation is the problem. That roof must be like a frying pan or something. I always try to buy white vehicles with light colored interiors for this reason.
I would have liked to know the temps of the wires on the DC side and inverter temps, they had to be working at their limits. I always step up my wire gauge size on the dc side and use OFC (oxygen free copper) wire. Like my go power 3000 watt pure sine inverter says use 4 gauge at a maximum of 6 feet i think? I am at just under 3 feet with 0 gauge. And the proper battery configuration to handle a large amp draw. I would have loved to go with lithium at 48v but it just wasn’t possible. I think anyone who is planning on running a load like an ac unit off an inverter should really step up to 24v at least on the DC side. That 4000 watt 48v magnum would be perfect, and someone mentioned using it as a stand alone just for the AC, excellent idea. Quiet AC and no worries about power strain. Better get a whole lot of those lithium batteries. So certainly not the cheapest way to go, but it would work just fine. Great video keep up the good work!
One of the benefits of not being a math (and electrical) genius is we get to just try it 🙂
that’s always the bottom line anyways, I don;t know how many times ive calculated things out and they work on paper but in the real world i get issues. At least you know you can run it if push comes to shove,
I love your videos and wish you had a new one everyday! haha i still have no idea what the max watts i can run are, i have nothing to measure above 20 amps or so. My old husky 750 watt inverter actually would run at 920 watts safely for as long as i needed it to. never tested past a few hours. So sometimes inverters are better than their rating. And only one way to to find out, real world testing. Ill bet that Magnum is a real workhorse and i wouldnt worry at all about being hard on it. Its built for that. great job on another excellent vid, whats the next one about? I am always checking, waiting….
Very cool. (no pun intended). I have followed you, RV Geeks and Technomadia on this whole solar story. So glad to see hybrid inverters starting to be more available. The idea of pairing solar and a smaller genset is really appealing and can offset a lot of the extra cost of the hybrid inverter. Curious however, in the video your panels were putting out about what the AC unit was using. So why would I need 700 amps unless I wanted to run the AC after my solar output started to fall. Also, your ambient temps during the test were not that high, would this be practical somewhere with 90 degree temps or should I stick with a generator?
The hotter the temps, the longer the A/C will run and therefore the more battery and solar you’ll need. I’d stick with the setup you prefer.
Curious if Coleman gave any rationale for the $300+ soft start kit rather than just a $30 replacement starting capacitor which are also designed to decrease starting amps? http://www.modmyrv.com/2009/05/27/rv-air-conditioner-hard-start-capacitor
In rush current on a typical air conditioner is 5 times the rated current. A starting capacitor does not reduce the actual inrush current, but it does supply some of the current from the start capacitor. A true soft starter lengthens the startup time and reduces the in rush by reducing the starting voltage. Once the motor starts turning, full voltage is applied.
That is also my understanding of a “soft start”.
Matteo Giovanetti from Micro-Air, Inc.
James is correct. Plase also see my reply to Brian below for more details about why EasyStart is totally different than a hard start kit.
We at Micro-Air totally understand that this specialized equipment doesn’t fit into everyone’s budgets. However, you have to look at the alternatives. Replacing the inverter or perhaps a generator with a larger one will cost you thousands. Other soft starts on the market also cost the same or even more. Therefore, the EasyStart is the lowest-cost and most reliable solution that not only really works well, but it also buys you compressor protection that a larger inverter/generator or a hard start kit could never deliver.
To show our appreciate and understanding to everyone here, especially Jason and Nikki, for the next two weeks, we’re dropping the price of EasyStart by $100 in our webstore. Please follow the EasyStart link provided by Jason above in the “Recommended Gear…” section, and enjoy the benefits of EasyStart.
Wow! What a kind offer. Thanks guys.
A little disclaimer: We did not request this discount and we are not receiving compensation in any way for this. As we mentioned in the post we don’t own the Easy Start but it did come highly recommended.
You could a big fat capacitor inline with your invertor to handle the compressor surge when it starts up. It probably acts the same way a soft start AC does to avoid the AMP spike out of the batteries.
Hello Brian. Your question isn’t an uncommon one. Larger start capacitors, or the “hardstart kits” as they are called, do provide some compressor start surge reduction, best case up to about 20%. Soft Starters are totally different, and the EasyStart mentioned in the article is even better yet. EasyStart uses advanced, microprocessor control to gently ramp up the compressor voltage and current, precisely timing the application and removal of a start cap. This technique involves phase measurements, self-adaptation, and fault monitoring. The net result is a compressor start surge reduction of 70%. In real numbers, the A/C in Jason’s and Nikki’s video was probably a 15k. This has a LRA (locked rotor amperage) of 71A! Best case, a larger start cap or a hardstart kit will drop this to about 55A or so. EasyStart will reduce it to about 22A, which is actually within the surge rating of the Jason’s and Nikki’s Magnum Inverter that was featured in the video. It really is quite amazing.
How do I know? I was one of the development engineers for EasyStart. It’s really quite an amazing product. Shop around, try the hardstart kit, but when you are ready for a reliable solution that really works, please check us out at Micro-Air, Inc. Thank you.
Electrical & Control Systems Engineer
Allentown, NJ USA
I am interested on the sail boat your looking to buy. I love the motor sailer. Cozy cabin and inside helm for those raining days. Where do you plan to launch it. The best prices I heard is to buy in the Panama Canel area. On the other side of water lift dams Canel.
We are heading to Florida next to get serious about looking. Once we do, we’ll start shooting out the updates.
Awesome to see the batteries not dropping below about 13.3 during that high amp draw. That beats the stink out of lead acid batteries! Thanks for the review and test!
Right! It’s still blows my mind how much better the lithium batteries are.
Not sure if has asked yet, but I noticed in your video before you conducted the test your voltage was 14.1, is that not too high for a LiPo battery?
Nah, these are LifePo4, slightly different voltages compared to LiPo, so 14.1 is just fine. It’s actually very slightly low for charging, but that’s OK since Lithium tends to be happy sitting mostly-charged as opposed to lead-acid batteries that do better at 100%
I hope it’s okay to ask but about how much would an RV like yours cost including the solar set up? Right now we just have a Class-c 26ft since we only use it part-time but I want to know how much to budget for when the time is right to go full-time and yours is pretty much exactly what I would want.
You can find most of this info here: https://www.gonewiththewynns.com/category/rvin/resurrecting-dinosaurs
First, love your site, and love your videos. You both have wonderful fun loving ways! I have a question about batteries….. We are so new to this RVing thing, and are planning on getting 3 batteries this spring to replace the one cheap thing our RV came with. And now I am really getting confused over the whole thing. My husband has thought he should get 3 – 12 volt agm batteries, and adding a little solar later. Are we going in the right direction? Or do we need specific solar batteries for solar and specific batteries that get charged by the engine when we are traveling? And should they be the 6 volt or 12 volt? I keep reading about people getting just the 6 volt batteries, now I read what you have said and you have a link to a solar battery…..help! Please “un-confuse” us! Thanks sooooo much! Janet and Tony
If you’re going to pay the extra money for AGM batteries over flooded lead-acid, it’s probably worth looking into Lithium Iron Phosphate batteries instead. They hold more power, weigh less, deal better with deep discharge and high current output (and input, for charging). They are more expensive, though, and since the products aren’t quite as mature they’re a bit less of a “drop in” replacement.
Solar will work with whatever batteries you get. Some (Lithium) will take better advantage of solar because they can accept a charge faster and more efficiently, but flooded lead-acid or AGM will work OK too.
In terms of voltage and multiple batteries, it depends on how you hook them up. People who get 6V batteries hook them up in pairs so they end up with 12V. The main advantage to the 6V batteries is that they tend to be designed for deeper discharge, for things like golf carts and battery backups. 12V lead-acid batteries tend to be designed for starting cars, so they can produce lots of current over a short period but don’t tolerate deep discharge well.
Janet it’s all about budget and how you like to camp. We tell most people to buy the RV first, travel, camp and see what they like/don’t like. After some use you’ll decide if you want to upgrade the batteries and add solar.
COMPLETELY from left field in consideration of the topic 🙂
My wife wants to know where you got the cool padded glass holders?! Like you, we do not really want to full-time and drink out of plastic all the time!
We have them listed in our store under “Kitchen Favs”: https://www.gonewiththewynns.com/store
What is the Brand name of the battery you are currently using? And is it the best choice for off grid?
We currently have balqon which we haven’t been able to get a hold of so we don’t recommend them. We are currently looking into lithionics for the boat.
Great work you two. This video will go down in history — right next to Thomas Edison, Alexander Graham Bell, and Evil Knievel.
Ha ha…and each of those gents just rolled over in their graves.
Lew Farber of AM solar put on 2000 watts of solar on our 2013 Winnebago 36M and we need to balance it out with LiFePo4 (or similar technology). We regularly produce over 100 amps of current on bright days but have no where to put it. Our plan was to put in 1200 AH LI and a second inverter for the leg that supports the A/C (and other high draw appliances) and use the power management system to aid in protecting the inverter. The soft start system will be a great addition to that plan.
Our big issues is the somewhat sparse (if not outright negative) information about most affordable Li battery companies with only AM solar as the exception. Since AM solar is on the west coast and we are on the east coast, a company closer that 2000 miles would be handy.
Your battery blog left the battery details out so I’m wondering if you have anything new to contribute now about sourcing Li batteries?
Our lithium batteries for the boat will most likely come from Lithionics as they are who we have been looking at most.
I’d like to know what the minimum is to be able to pull it off. Solar, batteries, etc.
Many of us can’t even fit that many panels on the roof even if we wanted to LOL
It will depend on the RV. How bid or small it is, which AC unit you have and so on. For our rig, we have the minimum.
Thanks for an organized, detailed report. I’m sure that this will inspire others to look closely at upgrading their energy systems. Perhaps a few other will actually make some phone calls like you did.
It also reminds me of an old saying:
“It is amazing what you can do when you’re handy with money.”
Very Good. Even I understood what you were describing.
Excellent! We know that glossed over feeling that can happen and try really hard to keep it simple.
You guys are great!
I spent hours and hours doing the math…researching what the historical average price of gas is, how much gas does a generator use, how much did your solar set up run, etc.
I had the hypothesis that while this is POSSIBLE, there was no way it was COST EFFECTIVE due to the high cost of entry.
For better or worse, here’s what I found: http://yarrvee.com/solar-rv-aircon-financial-frugality-or-folly/
I love it Jon! We got you thinking and you actually sat down and crunched the numbers. Excellent post! We do have a follow up piece where will do longer testing once we get in a nice and balmy climate. It wasn’t hot enough where we were to run the AC for hours on end. So we will see just how many hours we can realistically get and how it handles true summer temps in the humidity of Florida!
I’m guessing your Samsung residential fridge draws at least ~90-100 Ah daily. How do you power the refrigerator and rest of the house once you’ve blown through your battery reserve running the A/C? I’m thinking that at some point some additional amps are going to need to be generated.
Ah, don’t let the naysayers drag ya down! With the declining fuel prices these day, you could probably get a really good deal purchasing a TOPAZ nuclear power supply from the Russians. It produces a CONTINUOUS 5KW power output for 3+ years and weighs a mere 700 pounds – VIOLA, a/c power problems solved 🙂
I have been thinking a lot about upgrading our Tiffin 36LA to a setup similar to yours. One of my main motivations is to be able to run the A/C without the generator. I couldn’t think of any reason it wouldn’t work bit now that you’ve proven it will work I can’t think of a reason not to do it. Living in Central Texas we are BIG fans of air conditioning and that’s the main reason our generator has close to 700 hours in about two years. I have two Ryobi 1800 watt inverter generators that, when connected in parallel, will easily run one of our air conditioners with a lot less fuel use and noise than our Onan 7000 watt RV generator. The interesting thing is that once the A/C is started it will run nicely off of one generator. We have a really quiet Yamaha 1600 inverter generator that would work great in that role if I had a hybrid inverter. It is a hair louder than the Honda 2000eu. Either of these would be a good solution to extend the batteries at night. They are really quiet compared to the Onan RV generators.
Thank you guys for being the Guinea pigs for for this test!
I am really excited that it worked for you guys? I have seen a couple of really expensive Earthroamer RVs (they call them “Expedition Vehicles”) than don’t use generators for the A/C. When the batteries need charging they use solar or the main engine to charge them. They say the main chassis (Ford PowerStroke) diesel is both more efficient and quieter than any of the RV generators they looked at. They spend a lot of money on solar/inverter/battery package. Some of that cost is recouped by not having to buy a generator. Of course it saves weight and space as well.
I think a setup that might work would be to install a smaller window air conditioner in the side window of the living room slideout (Next to your open bar)… Say a unit like this – http://www.frigidaire.com/Home-Comfort/Air-Conditioning/Window-Mounted-AC/FFRA0511Q1/ It may look a little red-neck – but if you are boondocking out in the desert who cares… The smaller 500w AC has a much lower surge when starting and when running draws less than your solar array puts out… The only thing that might not work is the 5,000btu might not be enough to cool the livingroom space?… But maybe the bedroom could be cooled?…
Great Video as always, were you running just one air conditioner, or both of them?
just the one AC. our system couldn’t handle the 2 going at the same time.
It was really fun to be a small part of your video creation process and then to see how great it came out. With all this heat lately, just let us know if you need us to come back and re-wire the A/C through the inverter again. 😉
You guys are welcome anytime! Great company and your handy (pun intended)!
I love your story and your research. I think you really hit a home run when you suggested a Hybrid Inverter Generator. Considering total costs, (solar system vs hybrid inverter generator) gasoline at 99 cents per gallon, and my wife’s need for total comfort at all times it is my choice. Thanks again!
Thanks. Everyone’s needs/wants/budgets are different and there is more than one way to go about it. And that sentiment goes for most things RV/travel related. 🙂
Very exciting. Thanks for performing this test!
Many of these AC controllers have some ability to go with a “low” cool setting instead of an “auto” which will mean “high” at large temperature deltas (82-66)… I might suggest that you try again with a Low Cool selection, and see what the amps are, and maybe the surge will be less exciting when that fan kicks in at a lower power!
The 24 volt inverters are typically more efficient and can handle surges much better. That said there are low cost products that will balance traditional lead acid battery packs for those that tap the 12 volt portion of the battery bank by transferring current from the other half until they are equal (about 85% efficient). I am not familiar enough with LI-ION battery banks to know what balancers may be best. A friend has put 1200 watts of solar and 1050 AH of L-16 fork lift batteries in his 5W trailer. It would be interesting to see 1400 AH of LI-ION batteries instead to imagine the possibilities. We lived solar off-grid in a straw bale home in the CO mountains for 4 years, so adding solar to my RV’s was the right thing to do and I am always planning my next system. I have seen lots of solar/wind on many sailboats too!
That was really good information, but this is for day use only, and are you going to spend the whole day indoors? No way is it going to be effective for you at night. Sound like a toss up for me.
Yes, with our current set up this is not a 24hrs a day A/C set up. We would need a lot more battery for that. We can cool off the RV during the heat of the day (leave the kitties in comfort) and if it is so hot that we need AC at night, we would just go plug in somewhere. We did write that sentiment in the post.
Thank you for another concise and well thought out concept exploration and review. You guys rock! Have you considered wind generators and a removable mast for your RV to supplement your solar system, and possibly carry the charging requirements at night, or even cloudy days? These are very common in the sailboat live aboard world, as the real estate for solar panels is severely limited. while they can be very efficient, in general they will not replace your solar system’s passive generating potential except at night. https://www.emarineinc.com/categories/Marine-Wind-Turbines … fair winds and following seas… seadog173, aboard sv Rascal, (a Pearson 30)
edit for accuracy, the signature line above should read “no longer aboard the SV Rascal .” Yes, the second happiest day in a boater’s life, but with a good bit of melancholy…she is sold.
We have looked into wind options many times over the years and it never seems to makes sense for an RV. We have talked with many manufactures and really tried to find a viable, realistic solution but no dice so far. They are just to heavy, take up too much space and need to be up really, really high and secured really, really well.
Very impressed with this test. I can not wait for the day when and RV comes from the factory with a complete solar panel roof. My 38 foot gulf stream has a lot of open real estate on the roof and seeing your test coach has me thinking I could do the same.
On a completely different subject from solar have you guys ever thought of looking into a kelderman two stage air ride suspension system ford that ford f53 chassis.
Super cool post and video!
Certainly the more battery storage you have the better, but I presume an Auto-GenStart would be really be necessary so that you don’t inadvertently drain your battery bank below a safe margin.
Totally off-topic…what is the cutlery Nikki was using when she was cutting the lemons?
This is being done by roadtrek for awhile now. They have been running the entire class b rv off batteries. I know that to run any compressor device off an inverter you need to have more capacity than needed because of the startup surge caused by the compressor starting up. This can exceed the surge rating of the inverter if you are not over sized. I have had a problem with people plugging air compressors and fridges and yes air conditioners into my uninterruptable power supply. I was told by the UPS manufacturers that you need to have 5 times the capacity of the unit so if the unit pulls 1000 watts you would need a 4000 to 5000 watt inverter to make sure you do not hurt your inverter. The soft start unit helps the problem by absorbing the surge when the compressor kicks on. With this on the ac circuit you for the AC unit you could use a smaller inverter. Check out the Roadtrek E-trek.
Ok.maybe this thought never crossed anyone’s mind…why not use a dedicated inverter just for the a.c.? It has been proposed to use more than one smaller inverter instead running one gigantic inverter. Just thinking out loud.
You guys are as crazy as I am my 300 watt 2500 watt inverter two 450 amp gel batteries. Yes I could run the AC for five minutes! Then the charge controller will shut it down.
ha ha, but it would be a glorious 5 min!
Awesome test! You guys are sooo cool.
I’m geeked up about lithium batteries and bigger solar panels now.
The only thing your video did not show was an aerial view of solar and AC’s while running… 😉 (Drone Power!)
Joe the computer guy
Wow, that is way too impressive. Pretty cool. Curious what the RVGeeks did to switch whatever needed to be switched? If I recall this is the first time listing the battery manufacturer. Is that a thumbs up for the product? They are right near me in Clearwater. How awesome is that!?!?!?! I am going to miss you guys when you switch over to boating. But that is going to be an amazing adventure and for sure I’ll be listening in.
We’d tell you how we did it, Joe… but then we’d have to kill you. 😉
I like how you left the scene of the crime before they pulled the switch ;-)…
Ever hear of “plausible deniability?” We didn’t see a thing officer. 😉
Ha ha…so true. How bad do you really want to know?
Joe the computer guy
Lol, you’d have to find me first. Ya know, my home has wheels…
How long did you guys end up running the a/c for?
What was the percentage battery life left when you turned the a/c off?
We turned the A/C off at the end of the video so the statements in the video are correct.
Fantastic video Wynns! I’ve been waiting for a conclusive answer to that question. Much as I would love to do this, I don’t have enough surface area on the roof of my Thor Axis for that much solar. Considering a DIY ice bucket a/c instead. Thanks for the info!
We got the RV for transporting our two Old English Sheepdogs – somewhat larger than cats.
I would have thought it would not work; but you guys are trailblazers and we all appreciate your well thought out efforts and of course your videos. We have a small RV Sprinter Interstate Grand Tour Ext we just bought for the trip up and down 95 from Miami to Katonah NY and are just beginning RVing.
Just to make sure I got the math down correctly…
You got a 700 AH lithium battery bank so this means that it can deliver either 700 Amps for 1 hour or 70 Amps for 10 hrs…right or about 85 Amps for about 8 hrs.
So if your A/C needs 85 Amps, does that mean that your 700 AH battery bank (without solar panels here) could run your A/C for 8 hrs before it runs out of juice?
Ooooh, I can’t honestly say. That sounds correct but there are many factors that can vary that math. I wouldn’t run an A/C without having a beefy solar array or using the generator.
As you guys know – we’ve been running our RV AC off of our inverter and lithium batteries for well over four years now. And of course – we have also gotten the questions hundreds of times over the years about the potential for running the AC off of solar power exclusively.
And it is possible – sort of….
We wrote a post explaining all the tradeoffs, and what it would take to fully run an RV AC off of solar:
But as you’ve seen – even on the sunniest day with tilted panels, running the AC will still be pulling out more power from the battery than you are able to put back into it from the solar panels. You aren’t running the AC off of solar at all – you are just using solar to supplement the battery drain of running such a high load.
If you want more than an hour or so of AC run time a day off of batteries, you’ll still need to resort to using a generator to recharge things often – unless you have built a truly extreme solar system.
Where we find running the AC off the inverter most useful is on sunny days when we are out running errands. We can park and leave the AC running in the RV to keep the cat cool, without needing to leave a loud generator on. We do this all the time – and it works great.
– Chris // http://www.technomadia.com
I didn’t know you’ve been running your A/C off your lithium setup…I do know based on our test you’ve got WAY more than enough juice coming in from your solar to power one and maybe even two A/C units!
Thanks for sharing and tell Kiki to stay cool.