I'm 90% sure the existing 12v system has the charging feature on the camper from the factory, so I should be covered there. I'll probably just upgrade the existing 12v battery to a 200ah AGM as well.
Check my 48V RV Solar System Design
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David WTRS
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MGo board has both and comes in different thicknesses.
I'm the Greenest Newbie here. I start reading and searching my head starts spinning. I would like clarification on my specific build, any guidance would be appreciated. Building a 22ft all aluminum 'Full Time" travel trailer. Planning on 4800 watts of solar on roof in a stacked slide out configuration 6 panels on top of 6panels total of 12. Building a 48v 35kwh battery. I will power a 20,000 btu "48 volt" battery only operated mini split A/C unit 1200 watts max draw. My sticking point is on inverter I want to go will an EG4 all in one 6500w single phase. but plan on mounting under dinette don't want excessive fan sound coming from unit in living space?????. Would it be better to go with all Victron eq for inverter charge controller....It will cost a lot more but would it be worth it in the long run??.....that's the question.......I really like the plug and play of all in one. Please Help.
I'm an RV guy and a solar guy. I've never really done "off grid" RVs, but have had quite a few visit as part of being a Boondockerswelcome host.
What I can tell you is that a 22 foot RV does not need a 20K BTU mini-split. And I can tell you that with GREAT confidence living in Texas. I know RVs are generally insulated for crap. You CAN do it this way and it's better than using a traditional RV AC system (which is going to way over cycle) as the mini-split can cycle.
I own two EG-4s. I can also tell you that the version sold after 2/2023 are not setup for "mobile use" and need to be flashed with mobile firmware as well as need to be taken apart and a N/G screw added.
I see a number of "sprinter vans" that are "energy independent" and certainly don't have 4.8KW of solar. They can run HVAC systems for a number of hours (not all day) but can supplement for "all day" with additional charging from their high-output alternators. With a trailer, you can probably pull 20A from a break controller connector.
There is no plug and play solution for this that I know about.
If you're going to "build" this trailer, you bang for the buck is going to be in adding additional insulation (likely closed cell foam). As it's a trailer, you're not going to be in it while pulling it, so you just need enough power coverage to handle the refrigerator (and there are 12V and LPG versions available).
Tell us more about the "use case". You're going to have a tough time building anything that can do multiple 24 hour periods running AC even with massive solar arrays... It's simply "normal" (even here in sunny Texas) to get 3-4 days w/o sun. You'll need to plug in to charge or have a simple 2KW generator.
I rebuilt a 38’ travel trailer several years ago I presently use a 3500 watt AIO connected to 3200 watts of solar. I have 4 100 AH lifepo4 batteries connected in series for the 48 volt AIO and another 100 AH lifepo4 running the 12v systems of the rv. I use a 9000 btu mini split for cooling. I designed the solar for use in the North east US where state parks are primarily heavy shade and the spring and fall tend to be heavy overcast. By practicing conservation we are able to use the ac 24/7 if the days are full sun. I would prefer 3x the battery capacity as on sunny days the solar is not being used most of the time because the batteries fill up from empty in 3 hours. The ac ifs not adequate to cool our entire trailer but is sufficient to cool the 143 square feet of our living area during the day and once the sun is down and it’s rays are no longer hitting the roof and our 13 windows it is comfortable for sleeping in the entire camper.
Here is a few of my thoughts.
Weight be sure your trailer has enough weight capacity to handle everything you are putting into it. It looks like you will be adding about 1000 pounds of weight to the roof of your trailer. A poorly weighted bumper pull trailer can be nearly impossible to pull over 45 mph even if it is not overweight.
Fan noise. I use a low end AIO and it’s fans are not noisy enough to be an issue for us. Less noise than our fantastic fan. I can’t speak for the eg4.
Victron. I had neither the money or the space for a victron setup but If I did I would have used it. It is hands down the best equipment for mobile use.
Being green. Both from a pollution stand point and a carbon footprint standpoint I doubt a setup that size on an rv that size will be very green. Not mentioning the carbon and pollution emitted in the process of manufacturing the panels, , brackets, wiring, and batteries the extra fuel used to haul the rig around will more than offset the fuel that you would use by having a small generator for backup and a system 1/3 to 1/4 the size that you are suggesting. ( if you are conservative in your energy use the biggest challenge of the generator will be keeping it in running condition due to lack of use) you can offset your environmental impact a bit by purchasing used solar panels. (That’s what I did)
If you don’t have a lot of experience camping I would suggest that you do a bunch of rv camping before you build your rig it will save you a bunch of trouble.
Just wanted to say thanks to you and all the boondockerswelcome hosts. We found you to be a Godsend when we took our recent trip from northern NY to north east Texas just before Thanksgiving., there were no campgrounds open until we got to Kentucky. We enjoyed every stay on the way down stopping at 5 different hosts on the trip it was a great experience.
Was hoping to never plug in is that a pipe dream?...."Use case fulltime" is boondocking 28 days a month and plugging in at camp ground 2 days a month. As for the mini split yes a bit overkill hot and humid climates running on low setting as not to cycle as much. As for insulation using 1 inch Dow foam board R5.....We have no idea where we are going we like Colorado and never been north of there Mini split is also a heater down to 5 degrees, but never plan on staying somewhere long periods of time below say 35 to 40 degrees.................So you recommend smaller solar array and smaller battery??.....and buying a small generator to offset cloudy and rainy conditions...........because Im boondocking nearly all the time?......
It's not a pipe dream, it's just gonna be hard on a 22 foot trailer to stuff it full of enough batteries to run an AC for a few days.
It's a math problem. Do the math for how much power you're going to be using, how much power you can store, and ASSUME that you'll need to be able to go 3-4 days (minimum) without any solar assist at all. Likely substantially longer. My guess is you're gonna come up with a big number in terms of kWh.
A generator solves a lot of problems and is very marginal cost compared to what you're talking about doing.
People boondock for long periods of time, no problem. Like living off grid, it's about energy and resource conservation.
It's a math problem. Do the math for how much power you're going to be using, how much power you can store, and ASSUME that you'll need to be able to go 3-4 days (minimum) without any solar assist at all. Likely substantially longer. My guess is you're gonna come up with a big number in terms of kWh.
A generator solves a lot of problems and is very marginal cost compared to what you're talking about doing.
People boondock for long periods of time, no problem. Like living off grid, it's about energy and resource conservation.
If you don't mind me asking you what are your personal recommendations with a budget of $10,000. I can get 12 residential panels on my roof double stacked 6 on 6 with top panels on slide to expose bottom panels when parked...... Trailer was custom built to handle extra weight.....but if it were you doing just curious your take ... Because again I'm a newbie
What is your goal? You want to be able to boondock as long as possible? A 22 foot trailer won't hold that much water - a lot of this depends on the use case and how you camp. Is AC a "have to have" because you're camping in above 90 degree weather all the time?
Energy burn while camping is very different in the summer than it is if you're on a mountain in the winter (or really anywhere in the winter).
I'm happy to have a shot at a "suggestion" but there is no perfect answer.
I know there's no perfect answer because of so many variables, we will be traveling everywhere hot and cold .....but we will try to stay in 70 to 80 degree warm weather and no cold temps. under say 40 degrees when possible. Boondocking as long as possible that is the goal. A/C and heat is a MUST I have a wife "the boss"...lol We will have 125 gallons of water on board. I'm not an engineer but I am an aircraft mechanic so I know a little not much lol. My ears are always wide open for suggestions. Inside of trailer will be sprayed with lizard skin insulating paint "who knows if it really works or not" then 1" of foam board then the inside skin is 3mm Aluminum Composite Material. There will be two 30"x30" windows and four 48"x 24" windows in the trailer. Trailer inside height is 7.5'. I could use 2 inches of foam but does it really matter with so much window area? Trailer exterior is white to help with thermal transfer. Already bought 48 v A/C Heat Pump unit I know it was way overkill but plan on running unit on lowest cycle setting and hope for the best, it doesn't have to go through the inverter. As for batteries I'm building Three 48v 230ah batteries which will be around total 35kwh.....80% usage brings me to 28kwh. Plan on having a 48v hot water heater. We are putting in a washer dryer combo unit 120v and misc. 120v circuit's include induction cook top and pressure cooker and TV and Laptop......I could save some weight by only doing 6 solar panels on roof if I can find some 600w plus to maximize my roof area. If you were me having the experience in your trailer what would you do?......Im in limbo on inverter......should I go with all victron eq, Or would I be ok with a 3000w All in One?......A/C will draw around 1200w on high.....only other thing we need is maybe the hot plate burn1400w while A/C is running, could get by will 3000w inverter.....any suggestion would be greatly appreciated.....My home base is north of you In Edmond, OK....
littleharbor2
Solar Addict
Years ago, in my 5th wheel, I would reuse the water from the beverage ice chest. Once it came time to reload the ice chest we'd pour all the water from the melted ice into the freshwater tank. Every little bit helps. My buddy and his good intentions poured the water from the food ice chest into the tank without me knowing. The next time I used the 5th wheel I discovered an awfully funky tank of water from whatever was in the food water. Lesson learned. NO food water, just beer and soda water in the tank. ???
In a recycling system you still have a fresh water tank. The gray water tank is used after run through several filters and a uv filter for washing dishes, showering washing clothes etc... The fresh water has its own spigot and is used only for consumption. As long as someone doesn't put food water in your fresh water tank ?, your good.
That's pretty hard core. I've seen gray water used in "green" homes for flushing toilets, etc, but such a system on an RV.. Well, it better be a big ass RV.
I have considered a collection system for AC condensation. I assume the issue with this is largely that you're collecting water that's been exposed (possibly) to welds that have lead in them. I wouldn't drink it, but I know that our RV produces 5 gallons a day locally if we're running the AC.
The standard in the boondocking community that I've seen is simply to use less water - mainly in the shower.
There are youtube videos of people doing this with vans. With any rv since your only using the recycled gray water for non consumables your gray water tank actually is a second water tank. It eventually needs replenishing as its used for toilet flushing too. And yes it is pretty hard core.
littleharbor2
Solar Addict
That should be the standard everywhere. I lived on Catalina Island for 48 years. They
have salt water toilets over there. Too bad everybody on earth didn't use salt water in their toilets.
