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

[satyrsun]

So I'm in the planning stages to modding out some kind of van or truck - well not even planning, more like still brainstorming. I'd like to throw one out I had earlier today and get some feedback. This is an idea best geared for medium sized spaces (cargo vans, SUV's) but I think could definitely be tweaked for a very small space such as a hatchback.

I've colored the instructions red to separate it from the rest of the post.

When I lived in the dorms in college, we had a trick for bypassing our window units if needed to get AC, or to just get out a little extra cold air.

You need a

fan with a grill/guard in front the blades, at least a 12"
2 buckets
Copper coil (example)
clear vinyl tubing


The idea is simple but pretty elegant. You place your first bucket up on your desk, and fill it with ice water. You put the fan next to the desk, then place the final bucket on the floor on the other side of the fan.

From there you create a Siphon system.

You take a small length of the vinyl tubing, and get it snug over one end of a length of copper coil. The other end of the vinyl goes in the ice water bucket that is placed up high. Take the copper tubing, wrap it in a spiral around the fan grill heading towards the middle of the guard, securing along the way with whatever you have at your disposal. Then take the last end of the copper tubing when you've made your spiral and have come off the fan guard, put another length of vinyl tube over it, and place that end in the empty bucket that is on the floor.

To start it, you would suck on the end of the vinyl tubing that was closest to the empty floor bucket until water came out - then you put it back in the empty bucket and let gravity continue the process! (no matter how you've run your conduit, as long as the empty bucket is below the reservoir ice bucket wherever it ends, the siphon works).

The copper gets cold almost immediately from the ice water that flows through. The fan now blows cold air. Dump the used water back into the reservoir bucket when the cycle finishes, add a little ice if you need to, and start it up again.


The water lasts longer than you'd think - you can manipulate the slope and path of the tube into the empty bucket such that you can slow the water down as it travels.

The problem to solve of course is, how do we ensure we have a constant supply of ice water when you're on the road and not near hookups or such? There are plenty of options. If worst comes to worst you buy a bag from a service station for your ice chest, and feed a small bit to the reservoir as you need it (pro tip, you can mod a small ice chest to be your reservoir and make the cold last longer). You can also collect the ice water that drains from your ice chest.

What I'd say is the most self sustaining solution is to buy a portable ice maker (such as this one) that has the feature of re filtering water from the reservoir. Power the ice maker from a car battery that is charged via solar/wind power by using an inverter. Run the water that drains out through the ice maker every once in a while so it gets filtered and add it back to the reservoir. If your reservoir is big enough, pipe diameter relatively small and you route the water in the most efficient way to slow the water, you can get a decent amount of time from one fill - definitely enough to fall asleep. The fans can take care of the rest of the time by circulating the air.

Thanks for reading and i appreciate any feedback, or comments on how the general idea can be adapted to specific circumstances.

 

[Willy]

Buying ice will drain your pocketbook dry right quickly, and you've gotta be close enough to a store; probably pay more for gas to & fro. that ice maker is probably AC and, running off an inverter hooked to a battery, will probably suck it dry in no time whatsoever.. need a whole buncha solar/wind to keep it fed.

In a dry 'n hot climate a swamp (evaporative) cooler would be a better bet. There are also small, but pricy, 12v AC systems available.

If a person is dead set on going with ice cubes, of whatever size, than you could get a 12v compressor freezer to make your ice (Waeco, Engel, Whynter, etc). ..Willy.

---

OK.. spotted the manual. 120W AC 1.7-2.1A. Multiply by 10 and add another 20-30% for conversion losses. ..Willy.

 

[Lucky mike]

HHHHmmmm......Air conditioner 5k BTU ....109.00 walmart
Generator/ inverter..2200 watt........549.00 home depot
Generator/ standard 2500watt........299.00 Home depot
Gasoline/ 3.50 gal. / 4 hr. run time

I wont have to run around looking for Ice....I wont waste a gallon of gas everytime I need ice

I can run a microwave , charge my other things at the same time........just in convenience alone for under 500.00

and rather than use the bucket to melt Ice.....I can poop in it!!!!!

 

[Von]

Here's an "air conditioner" i plan on making eventually. It requires a small water pump

To improve on that video's design i would use a ice chest though. The ice would probably last twice as long as opposed to using a regular plastic container. And maybe insulating the tubing going from the ice chest to the Heating core would make it last a bit longer as well

Edit: I plan on using a mini freezer instead of a mini fridge in my build. So i will always have ice packs on hand if i needed them for that setup

 

[satyrsun]

I think i need to clarify some things first about this idea. I'm a little confused with some of the replies.

1.) The buy ice thing wasn't meant to be to say its worth doing this if you can only buy the ice. More meant that as - if all else fails, battery runs dry or your primary ice source bites the dust, you will never be without the cold air if you absolutely need it. I don't think it would be worth it if you didn't have a primary ice source.

2.) Correct me if I'm missing a piece of the power puzzle here. This is the setup I was thinking of going for.

a.) Wind and/or solar power mounted outside to charge the battery (or two). To be honest, I wouldn't even bother with the solar power myself, but in my situation I'm going to be mostly driving with my setup and not camping so much. While driving I don't need the AC system, it's only at night while parking and sleeping before continuing onto the destination. Obviously I can generate a lot of power from just driving on the interstate for a few hours with a small mounted turbine or two.

I was thinking something like this outside the rig to generate the wind power.
Turbine

b.) The battery is inside the rig. Car battery or marine battery. It is charged continuously while driving by the turbines.

c.) power inverter hooks up to the battery to change the power from dc to ac. I may have misread but I think i saw someone post that these could be over $500? No idea where you got that price from, Here's one on amazon that would give you far more than what you'd need with just the ice maker on.
1600 Watt Inverter - $117

3.) Not sure if someone misunderstood me on this or if I just read into a post too much, but I'm not advocating taking your whole kitchen and trying to run it off the juice from a car battery. When I said it was useful beyond just an ice maker, i meant that within reason - charging a laptop battery or the like. I don't even advocate having the ice maker running 24/7, only as much as its needed.

i'll make another reply in a moment individually cause I spotted a couple good points that i didn't think about.

---

Buying ice will drain your pocketbook dry right quickly, and you've gotta be close enough to a store; probably pay more for gas to & fro. that ice maker is probably AC and, running off an inverter hooked to a battery, will probably suck it dry in no time whatsoever.. need a whole buncha solar/wind to keep it fed.

In a dry 'n hot climate a swamp (evaporative) cooler would be a better bet. There are also small, but pricy, 12v AC systems available.

If a person is dead set on going with ice cubes, of whatever size, than you could get a 12v compressor freezer to make your ice (Waeco, Engel, Whynter, etc). ..Willy.

---

OK.. spotted the manual. 120W AC 1.7-2.1A. Multiply by 10 and add another 20-30% for conversion losses. ..Willy.

---

Explained the ice misunderstanding, never meant to imply that this is at all worth it if you choose that to be a primary ice source.

Thanks for pointing out the issue of the battery being drained - I absolutely didn't think about that. I actually did think one could use a mini freezer as well to freeze some ice packs constantly, but I assumed the ice maker could be more generally useful and would take much less power than a freezer, and I wouldn't risk running out of juice and having other things in my freezer spoil. It seemed more efficient to just tote along a 120 W portable ice maker instead.

Sorry I'm ignorant on this one, but could you explain the math at the bottom? let me know if i did any of this math wrong

I looked up a general car battery online, and it on the spec chart it said AMP Hr Cap @ 20 Hrs: 40

So again correct my math if i have it wrong, but to calculate how long it would take to drain a 12 v battery running a 120 W device:
40 Amp Hours x 12 v = 480 W

480 W / 120 W = 4 hours.
To be safe and assume a 15% loss in efficiency during transfer, we get
.15 x 4 = .6

So 4 hours - .6 hours = 3.4 hours of operation from a charged battery.

That seems reasonable enough to me, especially since you are generating a ton more power as you are driving along the freeway to juice the battery. I'd personally make ice, toss it in my ice chest, then drain the chest before going to sleep at night and scoop out some of the ice I made with it for the reservoir. In the morning, you can put the used water back in the ice maker to get refiltered to make new ice for the day.

---

HHHHmmmm......Air conditioner 5k BTU ....109.00 walmart
Generator/ inverter..2200 watt........549.00 home depot
Generator/ standard 2500watt........299.00 Home depot
Gasoline/ 3.50 gal. / 4 hr. run time

I wont have to run around looking for Ice....I wont waste a gallon of gas everytime I need ice

I can run a microwave , charge my other things at the same time........just in convenience alone for under 500.00

and rather than use the bucket to melt Ice.....I can poop in it!!!!!

I'm not sure what you're referring to with the price listings? I linked to what type of products i was referring to above and their prices.

A window unit is nice to have, but I hate the noise personally, it uses way more power than an ice maker would and i have no idea how you'd be able to power that on the go sleeping in places without a power hookup, and mounting it in a van or such can be difficult on multiple levels if the design of your van isn't conducive to it. This is meant as an alternate method to get cold air, especially in situations where a window unit seems like overkill in a small space.

 

[Optimistic Paranoid]

You're planning to drive down the road with a working wind turbine on you're vehicle?

I'm not an expert on wind turbines, but I'm pretty sure all of the commercially available models are designed to shut down if the wind goes above 30 miles an hour or so as a safety feature.

If it did work, did you even stop to consider the liability of having the equivalent of an unguarded airplane propelor on your vehicle?

Do you really think the cops would ignore something like this going down the highway?

Was this posted as a joke?

 

[satyrsun]

Here's an "air conditioner" i plan on making eventually. It requires a small water pump

To improve on that video's design i would use a ice chest though. The ice would probably last twice as long as opposed to using a regular plastic container. And maybe insulating the tubing going from the ice chest to the Heating core would make it last a bit longer as well

Edit: I plan on using a mini freezer instead of a mini fridge in my build. So i will always have ice packs on hand if i needed them for that setup

Very nice. I have seen designs like this to make portable AC units out of ice chests. What they'd do is take the ice chest and drill out where the cup holders were. In the drilled out cup holder on one end they'd attach a tube (much like the extension on a shop vac, the one taht is usually 2 feet long and ends with a curve at the opening) rising into the air with a cpu fan mounted in the opening of the tube (blowing air out). At the other end of the chest they'd attach another of these tubes with another small CPU fan in the opening that wasn't 2 way - it was a 1 way they'd mount in reverse so that it sucked air in instead of blowing it out.

The genius part was how they divided out the inside of the ice chest. Think of how a lighter is divided in the center, with a gap between the divider and the bottom. When there was enough ice water to submerge the bottom of the divider, it created two chambers - one of the hot air being sucked in, and one for the cold air being blown out. The hot air needed to pass under the barrier and be pulled through the water before coming back out the "cold blowing out" side. I've wanted to try making one of these, but i'm never sure what to use to cut through the top of the ice chest :blush:

Also I came across this guy's version of the ice chest AC on steroids a while ago if you're interested -

Here's an "air conditioner" i plan on making eventually. It requires a small water pump

To improve on that video's design i would use a ice chest though. The ice would probably last twice as long as opposed to using a regular plastic container. And maybe insulating the tubing going from the ice chest to the Heating core would make it last a bit longer as well

Edit: I plan on using a mini freezer instead of a mini fridge in my build. So i will always have ice packs on hand if i needed them for that setup

Very nice. I have seen designs like this to make portable AC units out of ice chests. What they'd do is take the ice chest and drill out where the cup holders were. In the drilled out cup holder on one end they'd attach a tube (much like the extension on a shop vac, the one taht is usually 2 feet long and ends with a curve at the opening) rising into the air with a cpu fan mounted in the opening of the tube (blowing air out). At the other end of the chest they'd attach another of these tubes with another small CPU fan in the opening that wasn't 2 way - it was a 1 way they'd mount in reverse so that it sucked air in instead of blowing it out.

The genius part was how they divided out the inside of the ice chest. Think of how a lighter is divided in the center, with a gap between the divider and the bottom. When there was enough ice water to submerge the bottom of the divider, it created two chambers - one of the hot air being sucked in, and one for the cold air being blown out. The hot air needed to pass under the barrier and be pulled through the water before coming back out the "cold blowing out" side. I've wanted to try making one of these, but i'm never sure what to use to cut through the top of the ice chest :blush:

Also I came across this guy's version of the ice chest AC on steroids a while ago if you're interested - Wilker Do's DIY AC Ice Chest

 

[Lucky mike]

I wanted to say that ,but I thought I was just getting irritated from not being able to help those with poor choices and good medications.

Some people do not research there own questions , and even worse do not research there own answers beyond you tube!

and then of course you have those that step over dollars to pick-up pennies......

and each year a new generation is born and only learns from the one before it then tries to improve on it!!...........Please let there be a God or we will all be doomed!!!!

 

[Bdog1]

Lol. Easy now....

From a practice standpoint, driving you have all the charging power you need, from your alternator. No need to buy/ build/ install anything else.

I'm no expert but I think you only get half of the battery rating to use without hurting the battery life also. Polk around here a little, there's a bunch of info. on battery banks and what you can expect to run and for how long.

 

[satyrsun]

You're planning to drive down the road with a working wind turbine on you're vehicle?

I'm not an expert on wind turbines, but I'm pretty sure all of the commercially available models are designed to shut down if the wind goes above 30 miles an hour or so as a safety feature.

If it did work, did you even stop to consider the liability of having the equivalent of an unguarded airplane propelor on your vehicle?

Do you really think the cops would ignore something like this going down the highway?

Was this posted as a joke?

No, it's not a joke. Try googling next time before making the assumptions, asshole.
http://www.truckcampermagazine.com/news/new-product-free-spirit-energy-wind-generators

If that guy found a way to do it, then it's not impossible. No, I don't want a full commercial turbine. If you had read my reply talking about the wind turbine specifically, you would have seen I linked one that is made for smaller scale things such as charging car batteries.

Yes, you need to make sure you don't go above 35-40 mph or else it would be damaged. I'd venture to say most do not have an auto shutoff. I was assuming that you wouldn't mount it directly into the wind, but I figured going 70 mph with it mounted in the center and back of your van, with wires running under the van and through the hood, you wouldn't go above 30. The turbine I linked originally may or may not be sturdy enough to handle even this, but I never said this idea was beyond refining or adaptation.

---

Forget it. If this is the way your community treats people who just bring forward their ideas, shutting them down and insulting them out of your own sense of superiority, then I don't want any part of it. I outgrew my ego and learned to treat people with mutual respect and kindness when I left high school, but some people never get that far.

 

[Lucky mike]

LOL........I am impressed you googled it!!

Now reread the article.....he is not driving down the road with it , if you did drive down the road with it you would get pulled over...road hazard dangerous to other drivers if it falls of....which most likely happen at the first low clearance you pass thru..

2......if you need to call someone an asshole , this would be the wrong forum for you and most likely any other forum out there that has some type of respect for its members.

At this time there is no turbine available for mobile wind power that works......or components that would sustain the elements they would be placed under.

wind power is not cost effective in mobile applications without some other source of back up power

 

[satyrsun]

LOL........I am impressed you googled it!!

Now reread the article.....he is not driving down the road with it , if you did drive down the road with it you would get pulled over...road hazard dangerous to other drivers if it falls of....which most likely happen at the first low clearance you pass thru..

2......if you need to call someone an asshole , this would be the wrong forum for you and most likely any other forum out there that has some type of respect for its members.

At this time there is no turbine available for mobile wind power that works......or components that would sustain the elements they would be placed under.

wind power is not cost effective in mobile applications without some other source of back up power

Took you long enough to make your point, would have been nice to have you say it from the start instead of coming out with your lecture. That is why I called you an asshole - you had no point to make except to insult me. You didn't reply to anything I sent back to you regarding your links to items that are irrelevant to this discussion and a sensationalist appeal to your argument - which wasn't even clear at the time. If this is treating your members with respect, I'd hate to see how you treat your own family.

Article only said to take the turbine down when winds exceeded 35 mph because of the risk of damaging the equipment. Not because of any legality. No, i would not make the assumption that a turbine mounted on the back of your vehicle would pose a significant enough hazard while driving to be pulled over by a cop. Your turn to google and show me the law that states I would with this specific setup. You have yet to prove yourself worthy of "take my word on it."

 

[SoulRaven]

"Nuts!"-General Anthony Clement McAuliffe

 

[Lucky mike]

pretty much .........again read the article.....notice the wind speed is for standing wind speed...(Stationary)....now I did not jump in and insult you ....please notice who did the posting.......I just pointed out facts , so now do the research on your own theory ....Ive been there , I live totally off grid and have for over 10 yrs....I know and understand the basics....you need to learn them first before trying to present your project ,

your missing simple knowledge
your definitely missing common sense on this one
and most of all your hiding behind a keyboard trying to instigate....

your absolutely right about one thing tho.....in your first post you said you were pipe dreaming basically , I totally agree

 

[satyrsun]

pretty much .........again read the article.....notice the wind speed is for standing wind speed...(Stationary)....now I did not jump in and insult you ....please notice who did the posting.......I just pointed out facts , so now do the research on your own theory ....Ive been there , I live totally off grid and have for over 10 yrs....I know and understand the basics....you need to learn them first before trying to present your project ,

your missing simple knowledge
your definitely missing common sense on this one
and most of all your hiding behind a keyboard trying to instigate....

your absolutely right about one thing tho.....in your first post you said you were pipe dreaming basically , I totally agree

Everything is a pipe dream until you execute it with inspiration and ingenuity. I understand you are more educated generally than I am on all the basics of these types of systems - but as I said, i never presented this idea as being fully formed. There are ways to execute the basic concept though, as it's already been done.

http://www.gizmodo.com.au/2014/01/s...-your-electric-car-and-you-can-drive-forever/
puts four small wind turbines on the roof of your car that generate electricity as long as you’re driving at least 40km/h, with minimal drag so as not to affect your gas mileage.

When available later this year, they’ll come in a simpler 25-watt version, and a more industrial 1000-watt model which can be used to keep a battery perpetually charging in an electric car. The extra power can also be used to run in-vehicle electronics like a Wi-Fi hotspot or an elaborate entertainment center, and just like their larger counterparts these turbines don’t mind a little bad weather.

---

You know, I missed the part of your post where you said I was hiding behind my keyboard trying to instigate. Ironic, as just saying this instead of replying to the actual content of my post to you is far more instigation.

I asked you to provide me proof of what you claim is general knowledge, you have failed to. Your assumptions that this is one, impossible and two, illegal have been proven false, twice over. For once, please reply to the content of my post instead of shooting some inflammatory comment about my character or how childish my ideas are.

Maybe you should send the guys who are actually manufacturing the turbines I Just posted a message to let them know that what they're doing is impossible and defies what you consider obvious general knowledge.

 

[akrvbob]

I am almost always deeply proud to own this forum. This is one of the few times I'm ashamed.

Whether Satyrsuns ideas are realistic or not, there is no possible excuse for treating him like this.

His basic idea of a simple AC at the heart of the post is very sound; true some of the other ideas may have needed tweaking, but that's the purpose of the forum--offering positive advice to make our lives better.

Satyrsun, I offer you my deepest apologies, we almost never act like this--call it a brain-fart.
Bob

 

[Donedirtcheap]

What happened to the good old days on here when you would just park in a motel parking lot, steal their ice and sneak in for a free breakfast?
You can stay cool for free, STEAL the ice.

 

[Willy]

Basically, with a lead/acid battery, you don't want to draw it down more than 40% of its' rated capacity, leaving it with 60%.. or so I've read. You CAN draw it lower, but you sacrifice longevity. The AH rating of a battery is also dependent on power draw: higher currents will give lower effective AH ratings, and vice-versa. The battery AH rating you quoted seems to be 40 AH total at a 2 AH draw (over 20 hrs). Seeing as the ice-maker setup would be drawing something like 10x an hour, the capacity of the battery could very well be significantly lower. Also, you should take a look at what the parameters were to give the 40 AH rating.. especially lower end, since most inverters have a low voltage cutoff and won't allow the battery to be drained beyond a certain point.

The conversion losses I was talking about are the DC->AC and the losses incurred when charging the batteries. I'm basically talking overall losses, though it might be higher.

Regarding the actual power being used, notice that the range they claim is from 1.7->2.1 A at 115v. That works out to 195.5-> 241.5 W. Now, if a 15% efficiency hit is factored in, we get 224.8-> 277.7 W used an hour. Given that a lead/acid battery won't give an even 12v throughout its' discharge cycle, it's safe to say it would be around a 20 AH discharge rate (as the voltage drops the amps increase in order to maintain a set wattage).

In regards to the roof turbine I'll just copy/paste from the commentary below the Gizmodo article:

"Zombie Jesus @zombiejesus
January 9, 2014 2:44 pm

Basically. Excluding weather, which these turbines are clearly not designed to take advantage of anyway, the car and turbines and air form a closed system.

The article's claim that the turbines don't effect your fuel efficiency much because they have minimal drag is plainly misleading, since the primary mechanism by which turbines work is drag. It takes a certain amount of kinetic energy to start and then keep fan blades rotating, and that needed energy is increased when the fan is connected to a generator, because it needs to overcome mechanical resistance. It's also inefficient (all generators experience energy loss in some form), so for the turbine to have minimal drag, it necessarily produces even less energy.

The fact it's attached to a much larger object is inconsequential. The amount of energy needed to accelerate an object or keep it at speed against friction is mathematically deterministic. Having a device that could constantly return some of the energy needed to move the object back into the system is a violation of conservation of energy, because it creates a 'discount' on the total energy requirements in the first place. If your car needs 10kw to move and your turbine returns 1kw, you're really only spending 9kw to move the whole system, which violates the maths involved and effectively 'creates' new energy.

The idea of putting a turbine on a car isn't new, it's been around for decades. It's a fairly well known example of a first-type perpetual motion machine."

Unless stationary (me here again and not the quoted guy) and taking advantage of a stiff wind you would be no better off than using your alternator to charge your batteries, fuel being used to provide the needed power in both scenarios.

Solar, on the other hand, would be a different story. ..Willy.

 

[Starlight]

I want to thank Bob for stepping into this conversation.:huh:

I was beginning to have thoughts that -- well, -- that the point was to run people off of the forum -- with insults and insinuations.

At one time, I, myself, had to overcome the temptation to think that everybody around these parts were in some sort of club -- like a nudist colony or swinger club -- until I realized that there are people of all kinds that hang out here... each with his/her own philosophies. It is an independent breed of people -- wouldn't you say??

 

[Willy]

At one time, I, myself, had to overcome the temptation to think that everybody around these parts were in some sort of club -- like a nudist colony or swinger club -- until I realized that there are people of all kinds that hang out here...

uhmmm.. can you, like, point me in the general direction of the nudist colony, or the swingers club? Both? C'mon.. don't make me beg! That just ain't cool. ..Willy.