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Tiny van, tiny (portable) AC?

Wiznaz

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Aug 18, 2020
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Hey guys, thanks for having me! I wanted to get some advice on finding a ~500W portable AC unit. I was trying to avoid a window unit due to continuously having to remove & reinstall it. I am aware that portable AC's are notoriously inefficient at about 50% compared to the window units. It would fit inside the van so much better though and there are already 2 side vents in the rear cargo area I can 3D print an adapter for to connect the intake & exhaust tubings to.

Due to the size of the van, I can only fit (1) 60 cell panel on the roof. I can bring along a 2nd panel to bump my array. I am also preparing to order a 24v 100ah battery bank setup from Xuba or similar. I understand the bank is too small to power the AC overnight. I already have an MPPT EpEver 40a Tracer but will also need a 24v inverter.

The objective is to have a comfortable vehicle to return to when I am out racing dirtbikes here in Florida before returning back to "normal" on Monday. Thanks everyone!
 

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I have a ~800 watt Frigidaire portable air conditioning unit that I've used in my RV trailer. I vent the exhaust out a port in the rear of the trailer. It works pretty good on shore power or the generator, but I haven't tried running it through the inverter/battery/solar. I may give it a try to see how badly it sucks the 225 Ah battery down.
 
I have a ~800 watt Frigidaire portable air conditioning unit that I've used in my RV trailer. I vent the exhaust out a port in the rear of the trailer. It works pretty good on shore power or the generator, but I haven't tried running it through the inverter/battery/solar. I may give it a try to see how badly it sucks the 225 Ah battery down.

Do you have the model #? I haven’t found a name brand portable less than 1000W yet.
 
Hey guys, thanks for having me! I wanted to get some advice on finding a ~500W portable AC unit. I was trying to avoid a window unit due to continuously having to remove & reinstall it. I am aware that portable AC's are notoriously inefficient at about 50% compared to the window units. It would fit inside the van so much better though and there are already 2 side vents in the rear cargo area I can 3D print an adapter for to connect the intake & exhaust tubings to.

Due to the size of the van, I can only fit (1) 60 cell panel on the roof. I can bring along a 2nd panel to bump my array. I am also preparing to order a 24v 100ah battery bank setup from Xuba or similar. I understand the bank is too small to power the AC overnight. I already have an MPPT EpEver 40a Tracer but will also need a 24v inverter.

The objective is to have a comfortable vehicle to return to when I am out racing dirtbikes here in Florida before returning back to "normal" on Monday. Thanks everyone!

Options:

1. Use solar panels to run a fan inside the car to exhaust the hot air via a vent somewhere. They make one that hooks onto the windows with a small gap so the hot air could be exhausted.

2. To save money and headaches, I would get an long distance car remote starter to kick on the car AC system so it could be cooler when returned. It takes around 15mins to cool a hot mini-van. The windows reflector type work very well to lower the inside temperature in the hot sun. You might want to cover all the windows will cool the mini-van space faster. $300 bucks investment vs solar that will be in the 2000+ range.

3. Solar is not ideal due to space on the VAN roof, power hunger of the AC and battery capacity run time. If you must, of course it is doable.
 
Options:

1. Use solar panels to run a fan inside the car to exhaust the hot air via a vent somewhere. They make one that hooks onto the windows with a small gap so the hot air could be exhausted.

2. To save money and headaches, I would get an long distance car remote starter to kick on the car AC system so it could be cooler when returned. It takes around 15mins to cool a hot mini-van. The windows reflector type work very well to lower the inside temperature in the hot sun. You might want to cover all the windows will cool the mini-van space faster. $300 bucks investment vs solar that will be in the 2000+ range.

3. Solar is not ideal due to space on the VAN roof, power hunger of the AC and battery capacity run time. If you must, of course it is doable.

Thanks Archetype! You make valid points. I'm prepared to tackle this project. Buying a small Honda generator will be cheaper but my mind is made up and I choose solar. I'm OK with the price I've estimated. I'm able to keep the cost lower because the setup is not sustainable. I only need it when the sun is up since I'm not doing any overnight camping. I am targeting a ~6hr runtime.

Using the the following items, here are rough numbers (without factoring any losses, AC setting max, perfect sun):

450W Air Conditioner, 300W solar panel, 24v 90ah Battery Bank

Only Battery: 2.16kwh ÷ 450w = 4.8hr runtime
Battery + Solar: 2.16kwh ÷ (450w - 300w) = 14.4hr runtime
 
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Thanks Archetype! You make valid points. I'm prepared to tackle this project. Buying a small Honda generator will be cheaper but my mind is made up and I choose solar. I'm OK with the price I've estimated. I'm able to keep the cost lower because the setup is not sustainable. I only need it when the sun is up since I'm not doing any overnight camping. I am targeting a ~6hr runtime.

Using the the following items, here are rough numbers (without factoring any losses, AC setting max, perfect sun):

450W Air Conditioner, 300W solar panel, 24v 90ah Battery Bank

Only Battery: 2160kwh ÷ 450w = 4.8hr runtime
Battery + Solar: 2160kwh ÷ (450w -300w) = 14.4hr runtime

Question - How long do you need to run the aircon (and any other loads) and how often?

What I'm thinking is it could just be once or twice a week (at events or practice) so you need enough battery+solar to run the load when you need it then enough solar to recharge the battery before the next time you need it.

Insulation is super important when it comes to any sort of aircon (heat or cooling) and something folks often overlook. In a van like yours, I'd suggest putting plenty of effort into insulating it. Polysio with Great Stuff is best, floor, sides and ceiling. On the windows you need reflective and insulated covers on when you are not in it.

Wills solar shed videos show how much difference it made to the power useage of his aircon unit.

Good ventilation makes a big difference in air quality. Getting the balance right is just a balance. If possible pull air from under the vehicle (floor vents) where it will be coolest (and therefore driest) and out through a vent on the roof
 
Question - How long do you need to run the aircon (and any other loads) and how often?

What I'm thinking is it could just be once or twice a week (at events or practice) so you need enough battery+solar to run the load when you need it then enough solar to recharge the battery before the next time you need it.

Insulation is super important when it comes to any sort of aircon (heat or cooling) and something folks often overlook. In a van like yours, I'd suggest putting plenty of effort into insulating it. Polysio with Great Stuff is best, floor, sides and ceiling. On the windows you need reflective and insulated covers on when you are not in it.

Wills solar shed videos show how much difference it made to the power useage of his aircon unit.

Good ventilation makes a big difference in air quality. Getting the balance right is just a balance. If possible pull air from under the vehicle (floor vents) where it will be coolest (and therefore driest) and out through a vent on the roof

That is exactly what my goal is. Use the system for 6hrs and then let it recharge all week. Rinse and repeat. The van is a passenger model so it has full carpet & headliner but I would prefer not to rip it out unless the van is still a sauna. I do have window shades though. The 2 vents the van has are a few inches above floor.

Edit: I don't really have any other loads. If anything maybe recharging a laptop & hotspot but I have yet to actually do that so far. My grill is propane. Oh yeah and a 12v cooler I can finally put to use.
 
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That is exactly what my goal is. Use the system for 6hrs and then let it recharge all week. Rinse and repeat. The van is a passenger model so it has full carpet & headliner but I would prefer not to rip it out unless the van is still a sauna. I do have window shades though. The 2 vents the van has are a few inches above floor.

Edit: I don't really have any other loads. If anything maybe recharging a laptop & hotspot but I have yet to actually do that so far. My grill is propane. Oh yeah and a 12v cooler I can finally put to use.
I'm afraid there wont be any real insulation behind that cosmetic paneling and carpet.

Look into R numbers. These are a measure of insulation and are used in calculations to determine energy needed to heat/cool spaces. Simply put higher R numbers = better insulation. The polysio panels have an R number of 6 I think

I used to live in Dubai so have an idea of what Florida is like heat and temperature wise. If you can feel the heat from outside on the inside of the walls of the vehicle the insulation is not doing enough and you will be using more energy than needed
 
Thank you for the pro tips! I will definitely look into this after I get the AC pumping
 
Thank you for the pro tips! I will definitely look into this after I get the AC pumping
It is probably wisest to use a small window AC unit and run from a 1500 watt, 120v inverter. Both are cheap and readily available.

However there are smaller air conditioners on the market. These run directly from 12v, 24v or 48v and "might" be enough to cool the interior of your van. They are roughly equivalent in capacity to a small automotive AC system.

 
It is probably wisest to use a small window AC unit and run from a 1500 watt, 120v inverter. Both are cheap and readily available.

However there are smaller air conditioners on the market. These run directly from 12v, 24v or 48v and "might" be enough to cool the interior of your van. They are roughly equivalent in capacity to a small automotive AC system.


That thing looks cool but it' $1k on Amazon and 1 star, 1 review. Like you said, a window AC seems to be the cheapest and coolest option. Only $150 and I can bring it back to Home Depot if I have any problems.

I picked up a panel today. 60 cell Silfab SLA-310M 310W Mono. Got it at a pretty good price around 47 cents per watt from a local vendor. Now I have to design a mounting solution for the curved roof. I'm going to 3d print something similar to the plastic mounts Will uses but with my own custom height for a drill-less install.

For those who ordered batteries off Alibaba/express, how long did it take to receive? The guarantees in the listings state October 28th. I don't think I can do 9 weeks if that's the norm.
 

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Ok, I just ordered a 24v Giandel 2000w pure sine wave Inverter and 24v 105ah Lifepo battery bank. I have some free time awaiting delivery from overseas so I will begin mounting the panel. The inverter is shipping from the US so I should have it in a few days. I may grab 2 car batteries and wire them in series to test out the AC unit with the new inverter.
 
It is probably wisest to use a small window AC unit and run from a 1500 watt, 120v inverter. Both are cheap and readily available.

However there are smaller air conditioners on the market. These run directly from 12v, 24v or 48v and "might" be enough to cool the interior of your van. They are roughly equivalent in capacity to a small automotive AC system.

Not even close to the capacity of the smallest car AC.... (which is average 30,000Btuh...)

these might keep a cooler box cold... about the capacity of a dorm fridge...
 
Not even close to the capacity of the smallest car AC.... (which is average 30,000Btuh...)
That's not what I keep reading--car AC can be anywhere from 4000 to 15,000 BTU, depending on make/model/who you ask/how fast the car engine is running....I guess people in the auto industry don't seem to care about BTU ratings. It really does NOT take a lot of cooling for a car interior.
 
That's not what I keep reading--car AC can be anywhere from 4000 to 15,000 BTU, depending on make/model/who you ask/how fast the car engine is running....I guess people in the auto industry don't seem to care about BTU ratings. It really does NOT take a lot of cooling for a car interior.
Yes... and this unit is 500 to 1800BTUH... so max is far smaller than the smallest car ac...

Remember, cars have LOTS of glass, and they are in motion, and they have constant fresh air recirculation when in motion... they need a lot of cooling.
 
eBay seller shipped me a Giandel 2kw modified sine wave inverter instead of the 2kw pure sine wave inverter shown in the listing. They accepted the return without issue. I wonder how many people never bother checking. Have to reorder from somewhere else now.
 
Went with their newer version of the WZRELB Reliable Inverter in the 3000w 24v pure sine wave flavor. Still waiting on batteries from the Group Buy thread.
 

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