Another DIY idea to solve the AC problem (small, green, quiet)

[SoulRaven]

I got this from somewhere and saved it off because the home made version is very similar to the one I use. I use the big blocks of ice, in a 7+ day cooler, and the ice will last 5-7 days, and the whole system draws just barely more juice than my fan alone.

12v air conditioners are the answer, they use little juice, and can freeze you out.

 

[Zil]

Thanks, Bob. Don't let the few of us wreak the rest.

 

[Willy]

Even better! [video=youtube] ..Willy.

 

[highdesertranger]

satyrsun just use your alternator to charge your battery. I am surprised nobody brought this up, but you will use more energy trying to make energy with a wind turbine on your car than you will get out of it. doesn't matter how small the turbine is the, the energy produced will be less than expended. if you think otherwise you have just invented the perpetual motion machine. which according to the laws of physics is impossible. highdesertranger

 

[Willy]

satyrsun just use your alternator to charge your battery. I am surprised nobody brought this up highdesertranger

Actually.. I did, though it was at the very end of a long reply. ..Willy.

 

[akrvbob]

I was very impressed with the idea of the 5 gallon bucket AC. That looks like it would work well to me.

All it would take is some solar and a 12 volt compressor fridge to have an unlimited amount of ice. Put that in the 5 gallon bucket AC and it should work.
Bob

 

[Zil]

As much energy would be put into the fridge to make the ice as would be recovered from the ice by cooling the van. Thinking there is some loss due to inefficiency. Why not skip the ice and use the fridge to cool the air flow.

 

[Optimistic Paranoid]

If the freezer is inside the van - IOW, it's in the same space you are trying to cool - this can never work.

If the freezer is outside, then, yes, in theory, this could work.

But I'd like to see some hard numbers: what's the volume of the space, what's the outside temperature, and what inside temperature do you wind up with? How often do you have to go outside to exchange a bottle of melted ice for a new one from the freezer? How much outside heat pours into the van every time you open the doors to exchange bottles?

I suspect that something like this is just too small to be real-world practical.

Regards
John

 

[GrayWhale]

Here's a guy making a lot of ice with:

portable ice maker ($150)
2 car batteries
90 watts of solar panels
1000w inverter

 

[Lucky mike]

the 2 car batteries probably died before the day ended....theres no=way the harbor frieght panels even came close to recharging the system....

 

[Willy]

I'm kinda thinking that, if a person was to do the 'making ice for air conditioning' thing, that a 12v compressor cooler (hooked up to solar) would be the way to go (funds permitting). This is cuz the time needed to make the ice takes place during the hottest time of the day and, while the mounds of ice made by the 120v ice-maker in the video look impressive, the 'cubes' are really small hollow cylinders.. not much ice there at all.

I'd think that, for air conditioning purposes, one would need a considerable amount of ice and, being realistic, a 'study' should be made re. how many BTU's it would take to melt a pound of ice, and bring the resulting water up to an 'unusable' temperature, vs. how much ice could realistically be made with a cooler/ice-maker.

not trying to be a Debbie Downer here.. just been disappointed too often in life and due diligence often pays off handsomely. ..Willy.

 

[Lucky mike]

I sometimes wonder some ways of thinking.....

the amount of solar panels and batteries it takes to make Ice or run luxury items (heater , A/C,Hot plates) ....just in basic set-up and additional cost of fuel due to weight....then you only get roughly a 10% return on stored energy.....

I spent a good chunk of change to build my system and found out first hand what happens when you abuse it....(I have 8 batteries onboard ,6 on solar) the system is for basic living..Lighting , refrigeration, charging stations , TV........

if I need A/C thats what the generator is for or I find available shore power......I just dont picture a boondocker or Fulltime vandweller wasting and damaging semi -vital equipment.

just the cost of having to start and run a vehicle to recharge batteries at an effective engine speed for a couple hours would change my mind.

figure it takes 2 hours to recoup the charge at say 1gph....thats 7.00....do that say 15 times a month and it just cost you a bit over 100.00 .....a hundred dollars is 2 months of generator fuel plus. and I get more for the dollar durring generator run time....batteries are charging....A/C is on....all charging modules are doing there thing....I catch a movie.....made popcorn in the Microwave and made hotwater for the shower.

 

[Optimistic Paranoid]

I gotta say I agree with you completely, Lucky Mike.

I didn't really understand the word "innumeracy" until I started hanging out here and started seeing some of these wild proposals.

It's not that they can't DO math, I'm sure. It's more that it never seems to occur to some of them to USE math as a tool to analyze the situation.

Regards
John

 

[offroad]

many do not realize battery technology. Lead acid, versus Lithum, versus others (NiMH, NICAD, etc). All these chemistry react differently to a charging and discharging cycle. Please read up on this folks. Am not an expert but it is tricky. Thus why you see complex expensive voltage regulator systems attached to batteries and solar panels.

You put a lead acid deep discharge battery on a system to power it, and you really can not bring the battery down too far, for more than a small while. We are talking going from 12 volts to 11 volts, and bingo you are damaging your charging discharging cycles (shortening it). Instead of going for 300 cycles of charge discharge, now you are down to 150, because you discharged that battery too much over a short time, and did not recharge it fast enough.

Again read up on this and realize you are going to eat up batteries and get expensive fast. Do not want you to believe me, but rather please read up on this all.

all this attached to a high power AC system could cause your experiment to go wrong with a waste of effort. be careful about design for the right power loads.

 

[akrvbob]

I don't see the problem. A 240 watt solar panel will easily provide all the power you need to run a 12 volt compressor fridge in the summer when you need ice for AC. No math needed, no magic, no running the engine or killing the batteries. If it's hot enough to need AC where I am, you got PLENTY of sun!

My Whytner 12 volt fridge has a Fast Freeze setting and it is FAST! No problem keeping ice frozen.

For the 5 gallon bucket AC I'd use milk jugs to make the ice and swap them in and out as needed.

As far as not able to cool the whole van space, that's probably true. BUT you don't have to cool the van space, you need to cool YOU. Just having a fan turned on you will make you significantly cooler but if it is blowing even slightly cold air (and i"m sure it would be cold) then it has to work.

That's why I like the 5 gallon AC, with the ducting you put the cold air where you need it, on you, not trying to cool the whole van.

It's all academic to me, as a snowbird if it's hot, I turn the key and drive to a higher elevation. Problem solved.

But a lot of people can't do that and this offers what seems to me to be a valid solution.

But it's expensive! Figure a minimum of $1000 for the solar and 12 volt compressor fridge.
Bob

 

[Willy]

I like that 5 gal swamp cooler idea that I found on Youtube. Just by itself, in a reasonably arid climate during the summer, it should cool down the air significantly. Add a bit of ice for when the temps get really hot and you'd have 'er made. ..Willy.

 

[Lucky mike]

Im with you bob within reason....I have 3 240 watt panels up there with a 4th going on after memorial day.......

its just freezing water takes alot of energy to do it ....if you put it in the freezer , the compressor will have to do double time to just get the temp back down to 10 deg. which is the thermostat cut out........normally it wouldnt run probably more than one cycle hour per day to keep it at temp....but adding gallon jugs or water in volume will create 4 hr run times....thats alot of power...

 

[SoulRaven]

The smallest portable air conditioner I can find draws 550 watts at 115AC.

I can’t see how this can be run using solar/batteries with the compressor running one half of the time.

Willis Carrier got the idea for what we know as modern air conditioning in 1902.

We are now in the 21st century and no longer harvest ice in the Pocono’s in winter, then store in using sawdust then ship it in insulated rail cars via a steam coal fired loco to Phila and NYC.

 

[Luisafernandes]

Where in poconos are you about? I'm near Gold Key Lake, near 739, and 10 minutes from I-84.

 

[SoulRaven]

Where in poconos are you about? I'm near Gold Key Lake, near 739, and 10 minutes from I-84.

I am just south of White Haven just south of the big road I-80 near the upper Lehigh whitewater under the old growth hemlocks near Hickory Run State Park.

I live in a van down by the river. LOL.