Portable 12V Air Conditioner --Cheap and easy!

Step 11: Possible Modification and Other Notes

We have some ideas for further modification that we may or may not implement. For starters, we will probably connect a hose to the heater core output. This will eliminate the burbling, trickling sound that is hard on one's bladder, as well as make it easier to drain. The ArcticAir units have a valve inside that you turn to redirect the output to an external hose so that you can drain the cooler out the window onto the flight line without wrestling it through the door. Another option would be a drain plug on the bottom, which is already on many models of coolers. We also are considering a vent system, so that the lid could remain closed while still allowing air to circulate. The ArcticAir units have a louver vent on one side for this purpose. A third modification would be some way to redirect the airflow. ArcticAir units have adjustable flaps over the fans, which could work, or some have a duct hose assembly to redirect the airflow where it is needed. A fourth, and painfully obvious, step would be to enclose all the wiring inside the lid or in a project box to make it look neater. However, for the time being, the zip ties are plenty for us. Also, we may try using Blue Ice-type ice packs, so that it would be reusable and not waste water.

This being a Go Green contest, I should put in a spiel about why you would bother with this. The main purpose is to make it more comfortable to drive a zero-emissions electric truck in Kansas in August. This runs off any 12V power source that can shove out 3 amps, so it can be used in other areas that need cooled, such as a hot workshop. Also, the ice lasts for hours when it's not running, and you can leave it on while you run into the store. The only disadvantage is that you could say it wastes water in the form of ice, but you can empty it out on your garden or lawn. It uses only ice water for cooling, which is about as non-toxic and environmentally friendly as you can get, and it kept a hose, a cooler, and a heater core out of a landfill. In other words, it uses environmentally friendly power to run environmentally friendly coolant through recycled parts in a zero-emissions vehicle. Can you get greener than that? I mean, this is #008000 at its best! Just make sure to recycle batteries.

Thank you for reading!

Comments

[cardmarc]

I made basically the same thing but used a 48 qt cooler with drain, and I installed a duct louver with adjustable lever for air intake control. But I got a cheap 4" Attword 12v bilge pump blower and connected it with 4" hose dryer tubing to the outlet of the radiator. 5 amp total draw. In any case, thanks for the lessons.
I put this cooler together for a total of less than $150 .

I had the 12V 230 cfm 4” bilge blower fan (~$30 now, Attwood 1741), a junk car 5”X7”X ~ 2” cabin heater core (~$15???), 4” dryer hose/clamps, wire, connectors, misc parts and pieces.

I purchased a 12V 500 gph bilge pump (Wal-Mart Attwood 4606-7, $18.66), some ¾” hose, a few clamps, a 4” dryer adaptor, some fuses, the intake HVAC diffuser with control lever (Home Depot aircraft supply), a 12 V on off switch, & the 48 qt cooler box with drain (Walmart, $25). Total about~$86 incl tax

It took about 5-6 hours to put together. Worse thing was cutting the insulated cooler to fit the parts in. I used construction adhesive and SS wire/screws for most of it. Total cost<$150+ my time as an educational endeavor.

On a 104F TX day (today here), it cooled the air to 65F until the pittance of water/ice from the refrigerator test ran out. (I didn’t purchase a couple of ice bags-will test that next-you put about a qt or so of water in to get the pump/exchanger to work).

4” Fan draw at 230 cfm=3.5 A at 13.6 V; 500 gph bilge pump=1.5 A. I used a 7.5 A fuse.

[twarner1]

The alternative to having this machine is having the existing AC fixed, which costs not only much more money, but is also more harmful to the ozone. A oil fueled Chlorofluorocarbon machine in essence!

[tazz1781]

While its a great project, its not all that green. For example, where does the ice come from? A machine that produces heat to make Ice and uses harmfull gases to do so. So, for the continued cost of the ice, whether buying it daily or having your ice box run more so you can provide your own ice, your really not saving any money or the enviroment.

[lloydrmc]

...and which "harmful gases" might those be, and in what way are they harmful?

[lloydrmc]

My "ice box" runs more? How much more would that be?

And agritzmacher has a point - how do you think electric cars are charged?

The raw materials and manufacture of Prius batteries requires 10,000 miles of transport, literally across the world: http://www.carkb.com/Uwe/Forum.aspx/car-driving/9345/A-Prius-Causes-More-Pollution-than-a-Hummer

Virtually all CFL bulbs - which we will be required to buy soon - are made in Chinese factories, fueled by "dirty" coal power plants. And they contain mercury, which, if the bulb breaks, requires approximately 6 types of tools and materials, and 14 steps (including cutting out a section of your carpet, if that's where it broke) - depending on who you ask.

[CameronSS]

Point 1: Do your research. Power from a coal power plant is cleaner than power from a gasoline engine.

Point 2: A CFL typically contains 4mg-5mg of mercury. The energy saved compared to an incandescent translates to something like 15mg-20mg less mercury vapor at a coal power plant.

Point 3: I made it to Level 2, I guess.

[lloydrmc]

Do YOUR research!
Point 1: Power plants in China (where virtually all CFLs come from) are NOT in any way shape manner or form: "cleaner than power from a gasoline engine". They have no scrubbers or any other type of pollution control whatsoever! In some Chinese cities, the smoke from power plants and other pollution literally makes it difficult to see for any distance, even at midday. http://news.nationalgeographic.com/news/2007/07/070709-china-pollution.html

Point 2: Try actually reading my comment. My comment was NOT about the impact of mercury on the environment in general but rather what a nightmare it is to have to clean up after a mishap with a CFL that we are going to soon be FORCED BY LAW to purchase, e.g.: http://www.maine.gov/dep/rwm/homeowner/cflreport/appendixe.pdf

Have you ever actually used a high-lumen CFL (such as a replacement for the soon-to-be-outlawed 100W Edison bulb)? It is recommended that they only be used in applications where they will be on for at least ten minutes, because it takes 5+ minutes for them to reach rated output

[CameronSS]

Okee dokes. Have fun.

[agritzmacher]

The same reasoning can be applied to electric vehicles plugged into the electric grid to charge... Just sayin'

[CameronSS]

The ice box runs whether we use the ice or not. We can turn it off, but that only shuts off water, not power to the freezing mechanism.

[tazz1781]

Yes, the ice box runs regardless, but it runs more to freeze water. How about using solar panels to run your portable cooler, or to charge the battery? Then you would have a somewhat "Green" portable AC.

[CameronSS]

Well, why do you think I'm tying to win? I don't need another bike...

[jpnagle59]

Cameron-- I live in Texas, Waco Texas, and so far this 'spring' we have hit 101 and 102 in my area. I have a 1993 Honda Civic, 200,000 miles on it, and the air is/has been gone now for a year and a half. This is one of the most brilliant ideas I have ever come across. Hat's off to you and your Father. I am late on this in terms of 2007, but I have a question if you could take a stab at it, I would be most grateful.
Do you think this design will cool a 4 door Civic to a comfortable level here in Texas when it is 100 outside? I suspect we would go harder on the ice, ie, it will melt quicker, but I am an older disabled person that has a harder time as I age with the heat. I sure would like to hear what you have to say to my questions.
I also wanted to say that I know the head of the physics department at UT Austin. I am going to ask him if there is a way to add something to the water to make the ice/cold last longer. Without using salt, and non-corrosive to the heat exchanger. If he gives me a good answer, I will let you know. one more thing- may I have you and your fathers approval to build your idea??? Tahnks so much, james

[actionjksn]

Why on earth would they put something on Instructables if they didn't want people to build it? This is what this site is based on, which is showing other people how to build what you built.

[CameronSS]

A Civic is pretty small, so it probably would. The ice wouldn't tend to melt any faster, it just wouldn't be as effective in a larger volume. Keep in mind, though, that a seven-pound sack of ice only lasts a couple hours, so it may not be cost-effective for all-day cooling unless you can find a place that has free ice. Here in Topeka, the Lindyspring water plant often dumps gallons of ice out on the lawn...a place like that would be good. Of course you can build it! That's the point of Instructables-to show what you built and how you built it, so that others can do it themselves.

[jpnagle59]

Thank you CameronSS...hats off to you and your father...

[bmlbytes]

The CC license he attached to this instructable would indicate that you were allowed to build this, and to modify it to your own needs: "This license lets others remix, tweak, and build upon your work non-commercially, as long as they credit you and license their new creations under the identical terms. Others can download and redistribute your work just like the by-nc-nd license, but they can also translate, make remixes, and produce new stories based on your work. All new work based on yours will carry the same license, so any derivatives will also be non-commercial in nature. "

[nicdinecola]

great instructable.. what about frozen 2-liters bottles? I plan on employing this type of technology to keep me cooler in my southern Louisiana shop. Thanks.

[mysss]

That's an excellent idea to reuse water and keep any additives (e.g. salt) out of the heat exchanger to prevent corrosion while still increasing cooling capacity/runtime. Cool!

[walkerman1980]

i have a good idea: although it does produce co2 (if the world had enough trees left itd be no issue though) try using dry ice since the lids open youd not have issues with pressure buildup or even better surround a "tank" of somesort with water in it for the pump with the dry ice. that way the water is seperated from the ice and it should last weeks. o2 cool used to make water mister "air conditioners" which worked suprisingly well but those add humidity to the air. awesome instructable thanks for the wonderful and much cheaper than store bought idea:)

[bneudert]

You would suffocate yourself that way if you used dry ice.

[nubzzz]

CO2 can build up and if it rises to a certain level is lethal. I would not recommend dry ice unless you had some sort of venting system.

[chestersgarage]

Most cooling systems use a compressor on the heat exchanger, which is one of the major energy inefficiencies. I assume your truck does not have regenerative braking, based on its age. But even if it does... I wonder if you could use the braking system to mechanically drive a compressor that re-freezes (or at least cools down) the ice. It would only run when braking and could be on a clutch that engages when the brakes are applied.

[LordJustice]

ooh great idea. but if on road trips then its not so good isit? :)

[dbshortwave]

If the Truck had an A/C system I would think of a way of using glycol, a coil of copper, hoses, and a bigger cooler and hooking it up to the Evap coil in the cars heater box. so you have to dump ice in the cooler to go anywhere its safer then some of the older A/C systems

[Gopher Mound]

Don't bother using the reusable ice blocks, I tried it some time ago and it just doesn't work. To work effectively it needs actual ice in water.

[italia.hill77]

I know I am a little late too since this was published in 07 but this looks really cool. And Green. It is just stupid to say it isn't green because you are just being wicked nit-pickity.

[lievesley]

Excellent project - well written, inexpensive, ingenious and GREEN. I see that this was published in 2007 so I'm jumping in a bit late, but I figured it was such a good 'real' project that I had to comment. Re. the ice: my wife and I have been using plastic bottles and jars (mayo and 2 litre juice bottles) filled with water and kept in our freezer as ice packs for our coolers for years. The same water is used over and over again. Also, blocks last much longer than cubes.

[zdlatham]

I agree this is not green. In HVAC terms it's called ice storage and is used sometimes in commercial buildings. You simply stored the energy your freezer used to reject the heat needed to form the ice like a battery so that you could use it later in your car. Some building cooling systems do the same thing by making ice in the middle of the night when power rates are low and then using the ice during the day to cool the building when power rates are high. Nice idea though. What would be better would be to use some of the wasted energy consumed when the vehicle is idling or stopping to make the ice.

[Danish M1Garand]

EV's never idle. This is a great idea. My fridge runs on non fluorocarbon 134a. If you bought off peak power for the icemaker it would use power that is aleady SURPLUS on the grid. It takes days to start or stop the Coal and Nuke plants so they are turning at full speed anyway at 4am.

[tazz1781]

Finally, someone else can see that this in not green in any way, shape, or form. Thank you.

[CameronSS]

Find me something that is entirely green and I'll agree with you. Until then, see below.

[CameronSS]

The only truly green solution is called rolling down the window. Oh wait, in doing that the mechanical system wears slightly and releases a microscopic mount of dust, which is know to cause cancer, birth defects, and dismemberment in the State of California. Truly, nothing is totally green. Any so-called "green" system will always have someone saying that it's decimating the population of unicorns and rainbows. The problem is to make things more green than they are now. If you had a car with a bad air conditioner, replacing it would involve highly toxic and ozone-depleting coolants, which will slowly leach out over time. It is the same as the argument that "EVs aren't environmentally friendly because the energy is produced by burning coal." Yes, pollutants are released in the production of coal, though wind, solar, hydroelectric, and geothermal plants could minimize that. However, the pollutants released by the coal are nothing compared to the crud that comes out of your exhaust. There is no perfect solution, but this is closer to it than a refill can of Freon-type refrigerant. Oh, and you don't get energy from idling in an EV. The motor stops, why waste power running it when it's not doing anything? Stupid ICEs...

[_soapy_]

Well said. Further, if you look at the charts provided for vehicle efficiencies, you will also see that, above about 30mph, it is better to put the windows up and use the AC in a modern well-aerodynamically designed (air-breathing, fuel burning) car, as it uses less fuel than that used to overcome the increased drag on the car from the rougher airflow.

[PerfectlySquare]

I'd be inclined to agree with both of you. This is certainly not the *MOST* energy efficient way to cool a car. That said, for the price it's outstanding, and quite eco-friendly. The batteries could be recharged by solar, the ice runoff could water your plants, and a majority of this system could be reused if one component fails.

How freaking green would this have to be before they give you credit? Who knows, but I'm growing tired of these "I recycle my own feces into tea, so I'm GREENER THAN YOU!" types.

Having been a Grist subscriber for a while now, I've had just about all the eco-pretentiousness I can stand. The truth is, you're miles ahead of 99.9% of the citizens of developed nations just for driving an electric only vehicle, and for seeking out homebrew solutions that not only save you cash but keep trash (like styrofoam) out of landfills.

Don't worry about just how "green" your idea is. It's a solid Instructable!!

[tazz1781]

Solid instructable? Yes. Green? In NO way, form or fashion. Anyways, it will be booted before the judging.

[Danish M1Garand]

Dude, he drives an EV when otherwise he would drive an IC engine car as it was too hot to drive without AC. Lighten up.

[CameronSS]

Er...have you seen the contest results? Read carefully...

[PerfectlySquare]

Nothing like getting 1st place to make your point, eh, Cameron? LOL.

By the way tazz, this project reuses *and* reduces , so according to the contest definitions, it was more than valid as an entry.

Why would it have been booted, when it says in the contest guidelines:
"So, reduce, reuse, repurpose, recycle, and rebuild, then show us what you are doing to make your life a little bit greener!"

Seems to me this instructable does just that...and it would seem the judges agree too.

[jongscx]

dude... I really could have done without the fecal-tea reference... 0_0