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diy solar

I am always fantasizing about having a energy efficient air conditioner for van life, anyone seen any concepts in tech news or anything?

Search for the ev request thread, the video linked showing the ev converted 10years ago, show that he installed a vs compressor ac system in his car. Links may show where and how he did it.
 
This one
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General info on electric vehicles

Hi, I'm looking for a good forum or website or book to get info on retrofitting Gas vehicles to electric vehicles, I have a general idea, DC or AC electric motor, controller, batteries, transmission, inverter if necessary, charging port and I guess a lot more details that I'm missing, I have...
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oldspice said:
ah yeah actually watched that the other day, but the amount of panels he has is absolutely insane. impressive slide out design but still. is that unit the most efficient available at the moment?
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When you look at the energy requirements of cooling..... that many panels become normal and ordinary. Especially if you expect to charge the battery some at the same time to continue the run after sundown.
 
A 3.1 cu ft mini fridge can be bought at Walmart for $130
Nearly the same tech needed for a mini AC

I have yet to understand why a 1000 btu miniaturized version of a 5000btu window unit has not been made?
I do believe the components are readily available?

Something about 10in wide x 12in deep x 7in tall using 500watts max startup surge and 100 watts running...on DC

All in the $500 or less price range. Millions would be sold if they were reliable
 
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I have been looking at using an aquarium chiller to chill the vberth on our boat. Simple installation, chiller, pump and radiator with fans. Units start at $500 on Amazon.
 
Just getcha a small LG winder unit with the inverter compressor to hang out the back winder. That'd probly freeze ya out though, but it runs on about 3 amps
 
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oldspice said:
as the title suggests, I am curious if anyone has seen any prototypes or DIY projects that could work? I feel like with the amount of tech we have right now it should be possible for such a device to exist...

anyone seen anything?
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look into mini splits. they are pretty efficient.
 
A good LG/Mitsu/Hitachi/Daikon mini split 10,000 BTU system draws around 600W at full rated cooling. At the min of 1,000 BTU they are around 200W.

Those units are about the top efficiency you can get.
 
We've do air conditioning in our Transit. Seems pretty rare so I'll share what I've learned.

We are running 400ah 24v battery storage with 800 watts of solar (24v) with Victron 3k / Mppt

We looked hard at the split units and the older style window air conditioners but my wife pretty much said hell no to a huge box on the back or the ghetto look of the window unit hanging out the back. We ended up going with a portable because a roof mounted air would have eaten up a lot of solar and our floor plan had ample storage for it. Had we gone with a split we would have been looking at a slight reduction in amps used our portable performs pretty damn good, efficiency would be better but this unit https://www.amazon.com/Air-Ductless-Conditioner-110-120V-Variable/dp/B01F5Z3JDE is only a few amp hours less than what we have right now.

Comparing power usage is like comparing budgets. Everyone has different needs and what one person thinks is normal another person is a hell no. We wanted to be able to run the air for the entire evening and be comfortable no matter where we were. That goal has been achieved.

We have a Wynter 14k portable. It pulls around 48 amps 24dc when it is running on high. That gives us a little over 7 hours of continuous run time. I don't care where you are or what temp you set the air conditioner at, you are not going to run it non stop all night. So there is plenty of juice to make it through even a very long, hot night plus other DC use.

When we get up, obviously the batteries are on the lower side. Again this varies based on use but we like it cold and comfortable. We have the solar which is really hit or miss on what it replaces. 4 800 watt panels (24v) do a great job of recharging a good chunk of the batteries assuming we have ideal conditions. Then again many times it is cloudy or raining or whatever. So solar isn't reliable unless you are in the desert. Even when we are in FL we see a huge swing in what we get and pollen is a real PIA. Anyway, 1/4 to 1/2 of the battery recharged via solar, maybe less. 15amps@24v alternator charging. So depending on how much you drive that could be a lot or not so much. The rest needs to be replaced with generator use. So 120v @ 30 amps, realistically if you were just charging the batteries you maybe could do all of it but lets say 25 amps 3000 watts / 24v 125ah. Lets cap the charging at 100ah or less. That leaves you using anywhere from 1-2 hours to 4 hours of generator use just to get back to full for the next night.

Hour or two isn't bad. 4 hours plus your regular day power use is a bit long. So it will vary.

Trying to run an air conditioner 24/7 off solar and only solar requires many more panels than you can actually put on a van. The problem isn't running it. You certainly run your air on DC. The problem is you don't have the ability to replace that power through solar nor the space to store the batteries which might allow you to run it for 3 days straight. Just isn't possible in a van with the foot print. You would have to have a solar farm on the land with you to get it done and something like 3 or 4x the number of panels I have on the roof right now and even then you'd still have days where you would need to run the generator a good bit to refill the massive battery bank that now takes up a lot of floor space.
 
About three years ago LG came out with inverter window ACs. They were kinda expensive. Last year Midea came out with their inverter window ACs. This year there are a couple more brands. The Midea works great but has poor power factor. 0.63 PF when compressor running at low speed(20Hz?) to a max of 0.74 PF when at high speed(120Hz). The LG 8K BTU conventional window AC, listed just below the VS LGs, has a 0.99 PF. I own both a conventional 8K BTU LG and a 8K BTU Midea. https://www.energystar.gov/productfinder/product/certified-room-air-conditioners/. Results sorted by efficiency.
 
oldspice said:
ah yeah actually watched that the other day, but the amount of panels he has is absolutely insane. impressive slide out design but still. is that unit the most efficient available at the moment?
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I don't know about efficiency, but there is a lot of detail and he made the problem work. I've seen nothing else except that YouTube video that documents a small build.

For my 35' RV in Arizona, the only thing I found that may work is one of the trailer mounted panel generators from the company that went bankrupt. They are for sale locally on Craigslist and have 8 panels, and probably 3200 watts of production with good battery storage. The ad said it weighed in at 9k. That is too big and heavy a trailer to tow behind my fifth wheel.

For the pic of the dog out the window, growing up in New England I never understood why people felt they needed AC until I moved down south. In AZ, I've seen 121° and that's hot, but does not feel as hot as a muggy 100° sub-tropical day.
 
chrisski said:
For the pic of the dog out the window, growing up in New England I never understood why people felt they needed AC until I moved down south. In AZ, I've seen 121° and that's hot, but does not feel as hot as a muggy 100° sub-tropical day.
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Agree.
I've been to Arizona and felt that summer heat at 115F plus and found that stepping into shade it feels cooler than a 95F day in high humidity.
The human body cools by evaporation. Tons of it in AZ, very little possible in the humidity of the deep South.
 
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