Step 10: Test Results

Picture of Test Results
We took the unit out to the truck for a test run when it was well over 90 degrees Fahrenheit (mid to high 30s for Celsius people). My dad set it in the truck and plugged it in, then went back to the house to get a camera. By the time he returned to the truck, the air inside had already dropped below 80, and the air was much drier, making it also feel much cooler.

I attached a PDF of JPEG of a scan of a notecard that my dad took notes on. What it basically says is the following: When the unit was started, the air in the cab was 95 degrees, parked in the shade after a morning of sun,and the outside heat index was 108 degrees. Within five minutes the cab had cooled to 75 degrees, and the air output was 65 degrees. With two quarts of water that had been refrigerated and 8 pounds of ice cubes, the ice had melted after 40 minutes, leaving 50 degree water, with an output of 65 degree air.

In other words, it works! And it works great! On Sunday, August 12 we brought it to Kansas City for a monthly meeting of our electric auto group. WE met in a small meeting room of a library, and ran the air conditioner off a small 12V battery on a table. Many of the members were impressed that they could feel the room getting cooler, and many tried to buy it from us on the spot. We are also in correspondence with an EV owner from Alabama who is eagerly awaiting the publication of this Instructable (I hope). If you're reading this, you know who you are, and I hope you like it.
Notes.pdf151 KB
casemill1 year ago

Um, you are using fans and coolant. Wouldn't it be more efficient to just use a refrigeration system? Instead of buying ice, which takes a lot of energy to make, you could use a normal refrigerant based unit. That way, you never have to replace the coolant. You know, a fan, a condenser, a heat exchanger, etc... Seems like you are doing something here that uses the same amount of energy to cool air as other things that cool air way more efficiently.

Can dry ice be used as a cooling tool.
jwall181586 years ago
Could it be possible to put an insulated cooler with the pump and ice in it inside your original design and seal the top. Have the hoses coming out of the sealed cooler to the heater core which is still connected to the cover of your orignal design.. I am wondering if your ice would last longer in a sealed or closed cooler. In otherwords, build a cooler with ice, water, and the pump and instal it in another cooler. Also, if you add salt to the water, I think it would lower the temperature or your ice and water combination.(kind of like making homemade ice cream)
Great! I spend an hour carefully crafting a reply only to have it eaten by some sort of software glitch. To summarize, changing the rate at which your ice melts simply changes the rate at which the device cools. Reducing GPM thru the heater core or slowing down the rpm of the fans to reduce airflow should also accomplish the same goal. On the other hand, the addition of an additive to the water which would lower its freezing point (antifreeze maybe?) would increase the cooling capacity of a given quantity of ice (assuming you were able to freeze the solution in the first place.)
desertdog5 years ago
Nice instructable.  I have a 1978 MGB electric car.  Most fun I have had in years was building it.  I had pondered the thought of some type of cooling for the occupants but had not done anything yet.  This is just what I needed to get me going on this for next summer.

Are all of your batteries located in the bed of the truck?
danzajax6 years ago
Why not feed the bilge back into your existing heater core? I assume since the vehicle is an EV it is not hooked up any longer. Even if it is, you could easily get a T with a couple valves from the hardware store to switch between heat and cool. Then you could run insulated lines to the cooler and mount it in the bed of your truck for that swank factory look. Nice instructable.
I love this idea. I am building an Electric Car and instead of ripping up the dash of the conversion car I wired up a heating element in the engine bay using a block heater. I am going to T off this system and put a Ice Chest Box with the bilge pump somewhere once I have the Battery Boxes constructed and in place. Then I can determine where it will fit. Great idea!!!
butthead957 years ago
this thing is sick but u should really make it so no air is running through the cooler ice will last longer
Maybe hook up one of the fans backward so it blows into the cooler. Or just mount it upside down. Then you have air going into the cooler and then back out. That way you can close the lid, and the air would have to go thru the coil 2 times and cross the ice so it should make for colder air.
put the heater core on the outside of cooler with fans on top with hoses thru the lid