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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.

The Test Location
Joshua Tree BLM South – Our EXACT GPS coordinates: 33.673887, -115.799702

Date: January 20, 2016

Time: 2:30 pm

Weather: Sunny with a 4mph breeze, High of 76°F

Our Gear
Here is the equipment that we have on our RV for this Solar + A/C test:

Coleman-Mach 15 RV Rooftop Air Conditioner http://amzn.to/1QhfCfs

Magnum Hybrid 3000 watt Pure Sine Inverter http://amzn.to/1oEnA63

GoPower! Solar All Electric Kit http://amzn.to/20zo7lC

9KW Lithium Battery Bank (700 amp hours)

Can You Run an RV A/C off of a Solar Setup?
As I mentioned above this is one of our most common RV solar questions. I noted in the video the solar power must first go through a charge controller then into a battery bank, and finally through an inverter to get power to the Roof A/C.

Based on our results in the video, with the proper technology and modifications the short answer is YES!

Should You Run an RV A/C When You’re Not Plugged In?
This is probably the most important question.  Of course the answer isn’t a simple yes or no because there are too many variables to consider.

How much money are you willing to spend on your set up? How hot is it where you plan to camp? What is the humidity level? How many hours a day will you need to run the A/C? Will the A/C need to be run overnight? etc.

If you’re designing a solar setup and willing to make some upgrades it is a real possibility but not necessarily a cheap one. With our current solar/battery set up and the addition of a soft start, we would run our Air Conditioner to take the edge off the heat only when the sun is shining bright. If temperatures get too hot, or there is intermittent cloud cover, we will most likely have to run the generator or head to a campground and plug in.

How to Wire your RV Air Conditioner to the Inverter
We did not cover this in the video because our install was done as a temporary install by swapping a few wires and a circuit breaker.  We would not recommend this to anyone looking to create a permanent solution.  We can only recommend you take your RV to a trained and licensed technician.  If possible find one that is also knowledgeable in solar, inverters and RV 12v battery systems.
What the Manufacturers Say
I looked up phone numbers online and began calling all the manufacturers of the products used in my Solar A/C test.  Surprisingly most hadn’t spoken to anyone before about any similar testing in the RV world.

I thought that was pretty crazy considering I’ve seen so many people pose this question over the years.  It always amazes me how few people actually pick up the phone and contact the manufacturer when they have a question about a specific product.

Below is an outline of what I talked about with the manufacturer of each product.  It gets a little technical, so if you’re starting to gloss over you should close this toggle and click on the next one that lists our recommendations without the detail.

I contacted Magnum and asked about the fault light I received for a fraction of a second during our test.  I was told: The 12v Inverters, including the hybrid inverter, are equipped for a maximum surge of 40 amps and the A/C unit draws a minimum of 61 amps while the compressor turns on.  Magnum recommended we consider upgrading to a 24v Inverter as they can handle a much higher amp draw.  They specifically recommended their Hybrid 4000watt Pure Sine Inverter which has a surge max of 82amps.  Magnum also recommended I look into a “Soft Start” or “Easy Start” for the A/C.

I called Coleman-Mach and asked about the power draw from the A/C and they confirmed the “Locked Rotor Amps” of our Coleman-Mach 15 is 61amps.  I was told: The Locked Rotor Amps (LRA) refers to the power draw of the initial startup.  Once the Air Conditioner has been run the first time, the oil will be out of the compressor and the coils will be saturated.  This means the compressor will need less power than the initial 61a when the A/C starts back up in order to keep the RV cool.  That said, they would not recommend running our RV A/C through our exact inverter, they recommended we look into installing one of the Power Saver models, specifically the Coleman Mach 1 PS which has a 41 LRA. I asked about a Soft Starter and I was told they have successfully used the Micro-Air EasyStart in the past.

I contacted Micro-Air and asked them about their soft starters, and which one would work with our RV A/C units.  I was told: The EasyStart 3T will provide a minimum of a 50% decrease in the Locked Rotor Amp (LRA), bringing the A/C amp spike to (or below) 31a. If we installed this product, it should allow us to run our A/C using the inverter without spiking past the inverter’s 40a max.  I was also told they have documentation and can help with the step-by-step process of how to install the EasyStart in a Coleman-Mach air conditioner.

Our lithium battery manufacturer has recently been impossible to reach by phone or internet, so I contacted the US Based Lithionics Battery.  I’ve spoken with these guys many times over the years and I’m sure our next Lithium Battery purchase will come directly from them (for various reasons I’ll share in a future article).  I asked them about the potential issues that could arise from us pumping in 55amps of power while continuously pulling out 80amps of power.  I was told: The lithium batteries and the NeverDie BMS are built for applications just like this. You will not do any harm to the lithium batteries by running the RV air conditioner. As long as the battery has ample charge you can run the AC for hours.  Those statements were quickly followed up by an impromptu disclaimer that went something like this: Now I can’t speak for any other lithium battery manufacturer and I certainly wouldn’t recommend doing this with traditional batteries.

I contacted GoPower! to confirm their solar panels, wiring, MC-4 connectors and the Outback solar controller could all handle the power needed to recharge the batteries while the A/C was running.  I was simply told: That’s exactly what the AE kit was made for, you won’t damage it!

I didn’t contact Fleetwood because this was kind of a secret test, you know, one of those ”better to ask forgiveness than permission“ sorta things.

The Recommended Gear to Run an A/C off Solar and Batteries
After discussing all the details & running through various scenarios with each manufacturer it seems like we’ve come up with this as a realistic option for running an A/C while camping ‘off the cord’.  By each item I’ve included a link so you may continue to research price, features & read reviews of each product.

Solar

With this exact setup you have the potential for a net ZERO amp draw, meaning you are putting in as much power into the batteries as you are taking out.

Inverter

You need a 3000 watt or higher inverter with a 40 amp surge rating; it does not have to be a “Hybrid” model (although if you have a big battery bank I would recommend the Hybrid models for their power share benefits).

Batteries

You’ll want a minimum of 700 amp hours of lithium battery power. The link above is the Lithionics 400ah battery, you will need to purchase two and connect them in parallel then add the BMS. If you’ve got the budget I’d consider stepping up to 900+ amp hours and if you wish to run an A/C day and night you’ll probably want to have at least 2000ah of power.

RV Roof Air Conditioner

With the EasyStart installed you can use just about any RV roof A/C unit that Coleman-Mach makes. I like this model because it uses less power, but don’t go replacing a perfectly good A/C if you don’t need to.

Soft Start

With this “Soft Start” installed you should be able to run most any rooftop RV air conditioner using a 12v inverter, even if the inverter has a 40a max surge and the A/C has a LRA of 61+.

Will It Work on A Boat, Tiny House, Etc?
YES! We’re in the process of testing the Easy Start on our Sailboat A/C unit now. So far it’s reducing the LRA by 70%.
Other RV A/C Off-Grid Solutions
While chatting with the manufacturers we also tossed around a few ideas that may spark a new line of thought.  They haven’t been proven or researched, but they were agreed upon by many of the people I spoke with.  All would still need some of the “Recommended Gear” modifications like the ones listed above.  Here are my three favorite ideas:

Volta Power Systems This is the future for RV power.  It’s a complete power system that is smaller, lightweight and substantially more powerful than current RV power systems.  The charging power comes from a high performance alternator, the power is stored in a giant Lithium Ion battery bank and the power is converted/inverted through a massive system.  Initial test reports relayed to me claim “In trials we ran 3 each 15,000BTU RVP A/C’s for +6.5 hours off the LI-ION battery bank”.  That sounds promising…and expensive!

Generator for A/C 1st Start:  1) Kick on the RV generator and let it warm up.  2) Once the power is ready (our generator takes about 2 minutes) turn on the A/C.  3) Let the A/C run for 5 minutes with the generator on.  4) Turn off the Generator and continue running the A/C by using the inverter.  This will effectively absorb the high surge from the initial A/C startup and the next A/C cycles will use less power.

Hybrid Inverter + Small Generator:  Using the “Load Support” feature of the Hybrid Inverter a small generator might be used to power the A/C unit.  Potentially something as small and compact as the Honda EU2000 could provide enough power.  The main benefit here is you can place the little generator further away from your RV so you don’t have to smell the exhaust or listen to it.

What about an RV Generator?
We prefer not to run the generator while wild camping because it sorta ruins it for us.  Being somewhere beautiful is fantastic, but having to listen to the constant hum and smell the exhaust fumes isn’t something we want to deal with on a regular basis.  That said, when Mother Nature decides not to cooperate (by giving us clouds instead of sun) we sometimes have to run our generator for an hour or two to make sure our batteries don’t drop too low.

Running the A/C off the generator is no problem as long as you have a powerful enough generator on board.  Our RV has a Cummins 7000 watt generator on board that has more than enough power to run both A/C units (at the same time) with plenty of power left over to run other devices within the RV.  Here’s a link to our generator: Cummins Onan RV QG 7000  We’ve also had the Diesel version in our past RVs and it works great as well: Cummins Onan RV QD 6000

I would also recommend an Auto Generator Start like this one: Cummins Onan EC-30w

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.

Famous for my "how-not-to" videos, and typically the man behind the camera, sometimes I’m forced to be here in the “spotlight”. When you see my face you’re probably reading something more technical than adventurous, but either way I do my best to tell it like it is and infuse my opinions into the commentary…after all this is a blog and not MSN.

Comments (162)

  • Ken

    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!

    reply
  • Bill Kidney

    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

    reply
  • Andrew

    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

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    • Curious Minion

      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!
      Curious Minion

      reply
  • inverterreview.com

    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.

    reply
  • Amina Gleckler

    5/18/2019 Appreciate this site– very informative and much to consider!

    reply
  • IronEdison

    Really interesting article and I enjoyed watching the video.

    reply
  • jenn

    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.

    reply
  • Shahbaz Anshari

    Yeah solar power air conditioner is efficient to cool the house while saving the scare resources.

    reply
  • Aaron

    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

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  • Bryan

    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.

    reply
    • Billy

      Voltage X amperage = voltage
      100amps 12volts=1200watts
      10amps 120volts=1200watts

      reply
      • Billy

        Sorry voltage X amperage=wattage

        reply
    • 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.

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  • Jaroslaw

    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.

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  • 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

    reply
    • Curious Minion

      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.

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  • Doug

    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!

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    • Curious Minion

      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.

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    • Donald Steele

      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.

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  • Dwight

    How much weight did this system add to ur rv?

    reply
  • Rick

    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!

    reply
  • Joey

    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!

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    • Joey

      Thank you for testing this out!!*

      reply
  • Dominic Owen

    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…

    reply
  • Carl Davis

    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?

    reply
    • We are working on this for the boat and yes there will be an update! Stay tuned…its going to be a good one!

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  • Mark A

    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.

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  • DL Renollet

    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…

    reply
  • James Marvin Cook

    Hi,
    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.

    reply
      • James M Cook

        Thank you, I look forward to hearing from you.

        reply
        • 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!

          reply
  • Gabriel

    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.. 🙂

    reply
  • Bob Maier

    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.

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  • CJ

    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.

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  • larry

    You just need to get rid of the inverters

    http://www.geinnovations.net/solar_air_conditioner.html

    reply
  • Tig

    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.

    reply
  • Rod Reichardt

    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.

    reply
  • Have you considered looking for a boat in Canada?

    http://www.sailboatlistings.com/view/54459

    Im not the seller but I do follow your exploits so when I saw thus, I thought about you two.

    reply
  • Brian Litz

    Truly well done!!!! I am a sailor so I look forward to your change to the boating world!

    reply
  • Joe Calise

    A swamp cooler, AKA Turbokool would have been a better item to test and has worked in the deserts for decades.

    http://www.turbokool.com/

    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.

    reply
    • Yes, but a swamp cooler only works in a dry desert and not so much in the rest of the world.

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      • Joe Calise

        HI, Nikki,

        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.

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      • 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

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        • Walter

          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.

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          • Curious Minion

            Nice summary! I didn’t know about the mosquitoes – yuck.

    • illya

      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

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      • Frank zoe

        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.

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      • Tucker Berg

        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.

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      • om using your link?

        As usual Jason, you are on top of your game, which we sooooo appreciate!!!

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  • 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!

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  • Leo Lanham

    Does your fridge already have an easy start or would the easy start be beneficial for it’s operation as well?

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  • 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.

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  • dave

    very informative! Thanks!

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  • Marsha Cowan

    Cool!

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  • Chris

    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?

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  • Adam

    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 🙂

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  • Tom Bondurant

    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. .

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    • 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.

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      • om using your link?

        You guys are incredible to share that type of info for others to profit from. Blessings to y’all

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  • 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

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  • 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.

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  • Ron

    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.

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  • Ralph Alder

    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?

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  • shaun Murphy

    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

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  • 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…

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  • David

    Hey Guys,

    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 …

    BTW

    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

    David

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  • 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.

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      • 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.
        https://youtu.be/ANIkLjDEZjE

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  • illya

    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!

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      • illya

        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….

        Thanks, illya

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  • Brent Farler

    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?

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  • Nik

    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

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    • James

      Nik,

      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.

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        • 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.

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  • Brian Biggar

    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.

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    • 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.

      Matteo Giovanetti
      Electrical & Control Systems Engineer
      Micro-Air, Inc.
      Allentown, NJ USA

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  • Bob Lantinga

    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.

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    • We are heading to Florida next to get serious about looking. Once we do, we’ll start shooting out the updates.

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  • Tab

    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!

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    • Right! It’s still blows my mind how much better the lithium batteries are.

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  • Gary Wydra

    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?

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    • Elliott

      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%

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  • Annette Bissinger

    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.

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  • 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

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    • Elliott

      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.

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  • Bob Williams

    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!

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  • John Puccetti

    What is the Brand name of the battery you are currently using? And is it the best choice for off grid?

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    • 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.

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  • Great work you two. This video will go down in history — right next to Thomas Edison, Alexander Graham Bell, and Evil Knievel.

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    • Ha ha…and each of those gents just rolled over in their graves.

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  • 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?

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    • Our lithium batteries for the boat will most likely come from Lithionics as they are who we have been looking at most.

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  • Lisa

    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

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    • 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.

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  • John S.

    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.”

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  • Terry Apple

    Very Good. Even I understood what you were describing.

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    • Excellent! We know that glossed over feeling that can happen and try really hard to keep it simple.

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  • 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/

    -Jon

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    • 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!

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      • Steve

        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.

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  • Michael

    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 🙂
    https://en.wikipedia.org/wiki/Nuclear_power_in_space

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  • Rod Reichardt

    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.

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  • Kevin

    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?…

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  • Brian

    Great Video as always, were you running just one air conditioner, or both of them?

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    • just the one AC. our system couldn’t handle the 2 going at the same time.

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  • 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. 😉

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    • You guys are welcome anytime! Great company and your handy (pun intended)!

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  • Gery Bauman

    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!

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    • 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. 🙂

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  • Corey Jackson

    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!

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  • 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!

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  • Bill

    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.

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    • 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.

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  • Jim Costa

    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)

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    • Jim Costa

      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.

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    • 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.

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  • chuck allen

    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.

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  • Jim Hummel

    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?

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  • 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.

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  • Joel D.

    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.

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  • John Puccetti

    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.

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  • Eric

    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!)

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  • 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.

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    • We’d tell you how we did it, Joe… but then we’d have to kill you. 😉

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      • Kevin

        I like how you left the scene of the crime before they pulled the switch ;-)…

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        • Ever hear of “plausible deniability?” We didn’t see a thing officer. 😉

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      • Ha ha…so true. How bad do you really want to know?

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        • Joe the computer guy

          Lol, you’d have to find me first. Ya know, my home has wheels…

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  • dean

    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?

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  • Peter G

    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!

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  • John

    We got the RV for transporting our two Old English Sheepdogs – somewhat larger than cats.

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  • John

    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.

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  • Merlin

    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?

    Thanks

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  • 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:
    http://www.technomadia.com/2015/02/the-almost-fantasy-of-solar-powered-rv-air-conditioning/

    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.

    Cheers,
    – Chris // http://www.technomadia.com

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