If we can get to space we can power an RV AC via car…

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Spyderstevens

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Ok so I don’t have a question as to “IF” we can operate a camper AC constantly on power inverter, car alternator, and car battery (batteries), but rather how. Call me a dreamer but there has got to be a way to do this. What equipment would it take (even if attached solar to a power inverter/converter would this take? How many batteries in the vehicle and how big of batteries in parallel would it take? Someone come up with a scenario beyond “it can’t be done. Thank you 👍🏼😎
 
First you need a more electricity efficient RV air conditioner such as one of thoe mini split systems with DC inverter drive compressors. Then you need a heavy duty alternator and a much larger battery bank.
 
Well assume they are about 15 A for the AC at 120V, 1800W so you need a 2000W inverter.

To get that much power out of an inverter you need to put at least that much into it, if it's from a 12V battery you need to draw 150A (ignoring losses) and then factor in time - for one hour of AC you'll need 150Ah of battery power. That can be pulled from a pair of 12V Deep Cycle batteries.

To run it all the time you will need 48 batteries. (24x2)

To recharge the batteries you will need 43200Wh of energy but if you only have about 6 hours of good daylight that means 7200Watts for 6 hours. At 100W per panel you need 72 panels, I'm not sure you could fit that many in a campsite let alone on top of an RV.

At $200 per panel and $100 per battery that's about 20K

It could be done if you didn't need it to be portable, set up the panels in an array on some land beside the trailer and build a dedicated building to house all the batteries.
 
Most RV A/Cs draw around 1300 watts. that's like 110 amps at 12 volts.
Your car's alternator can't do that. it will burn out
A honda EU-2000i is going to struggle A pair of them in parallel will do the job.
A EU-3000i... might but those are heavy
Anything over 3500 should.
 
If you get on the utoob you'll see videos where it's been done. Missing from the videos is how they guy paid for the half million dollar bus, 20 solar panels on top of it and the bank of 12 lithium batteries. You can do whatever you can afford.

Mark B.
Albuquerque, NM
 
Jay laid out the constraints pretty well.

On the boat we had a portable AC. The key for us was to cool the cabin at night to take the edge off for sleeping.

With 8 trojans and 800W of solar we could run the A/C for an hour or so at night to take the edge off. No way you could do something 12 X 7.

We also had an on-board genny and more often would often run the genny for a couple of hours around dinner time to run AC, microwave, make hot water and make drinking water (desalinator).

100+ miles off shore you really are boondocking and learn a lot about conservation - LOL...
 
Yep, it can be done. With enough $$ and enough space & weight-carrying capacity to handle the necessary equipment. There is even a Facebook group for folks who are gung-ho on RV air conditioning via solar power.

You need a lot of battery capacity (amp-hours) and a lot of generating capacity (alternators or solar panels). Plus a 2000+ watt inverter. A more efficient a/c than the typical RV roof system helps too. Even a home window a/c is a more effective chiller.
 
Ok so I don’t have a question as to “IF” we can operate a camper AC constantly on power inverter, car alternator, and car battery (batteries), but rather how. Call me a dreamer but there has got to be a way to do this. What equipment would it take (even if attached solar to a power inverter/converter would this take? How many batteries in the vehicle and how big of batteries in parallel would it take? Someone come up with a scenario beyond “it can’t be done. Thank you 👍🏼😎
forget the car stuff, not going to work..
it can be done, I would ask you how big is your wallet and how big is your RV ?

it's going to get expensive and require a lot of real estate for those panels.
as a simple exercise I have calculated the panel wattage for a 1000 Watt high efficiency
a/c running at various duty cycles in the summer time, not the best or worst case but what could
be a typical load.

100% DC = 6600 W of panels and 1100 A/hr at 48V or 52.8 kW/hr
50% DC = 3300 W of panels and 550 A/hr at 48V or 26.4 KW/hr
25% DC = 1650 W of panels and 275 A/hr at 48V or 13.2 kW/hr

the battery capacity will allow for 2 days autonomy.
the question here is: where are you going to store all those batteries ?
and will your RV have the load capacity for them ?

1100 A/hr of FLA will weight in at approx. 2800lbs
1100 A/hr of lithium will be approx. 1300lbs

so now the horror story.. the cost.

approximate market cost:-
6600 W of panels = $5500
1100 A/hr battery = $25000
MPPT Controllers = $2000
inverter = $2000

excluding cabling and installation the total is close to $35,000

get the idea ? LOL

what I would suggest is a 40 foot bus and a towable battery storage trailer, you could load the bus and trailer with that amount of panels and batteries and keep a small portion of the bus cool..

so seriously, 24/7 isn't going to happen, perhaps overnight for comfortable sleeping..
then you might get it down to say 33%, that's now "only" an $11,500 price tag..
 
Hey, if we can keep ice cream hard with an absorption fridge why can't we keep the trailer cool with some modified form of the same? It would still need a battery for fans but it would run on propane.

I can't be the first to think of this, can anyone tell me why it hasn't been done?
 
Hey, if we can keep ice cream hard with an absorption fridge why can't we keep the trailer cool with some modified form of the same? It would still need a battery for fans but it would run on propane.

I can't be the first to think of this, can anyone tell me why it hasn't been done?
It's s matter of scale. Absorption refrigeration is very inefficient compared to compressor driven refrigeration, the only reason it's used in an RV is the tremendous amount of energy in a gallon of propane.. It doesn't take much to keep a sealed, insulated box cold, a 50 watt compressor driven refrigerator produces the same amount of cooling as an absorption refrigerator.

Look at the size and weight of the cooling unit in an absorption refrigerator. It would take something 20 to 30 times larger (with correspondingly higher propane consumption) to get as much cooling as a single rooftop a/c.
 

If we can get to space we can power an RV AC via car…​

If you change "car" to "vehicle" then that might be true, at least to a limited extent, but keep in mind that going to space and air conditioning are completely different technologies, and even with the modern day "miracles" of technology, there are many things our scientists have not figured out -- also consider that the laws of physics cannot be flouted, and that space flight is still very, very crude.

However there are plenty of answers above to demonstrate why, at the least, you must change "car" to "vehicle." So set your expectations a bit lower...
 
LOL, I guess none of you believe the folks posting in that FB group I referenced. I don't argue that it is practical, but it can be done if you work hard at it. And you don't have to be a Saudi prince to afford it (but it helps).
 
LOL, I guess none of you believe the folks posting in that FB group I referenced. I don't argue that it is practical, but it can be done if you work hard at it. And you don't have to be a Saudi prince to afford it (but it helps).
I cruised that FB site and it appears to be full of hopeful people trying to get ready for winter, or people looking to sell stuff.
 
BTW - putting that many batteries in parallel would not work. It would requite a very exact series-parallel wiring. You would need to pay an expert to do the wiring. The wires would be as big as your thumb, and that is just the copper. With insulation the wires would be really big, not to mention very pricey.
 
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