Convert car air conditioner for home use (single room)

I've been into biomass gasification for years. I'm also building an office in half of a 40' shipping container. I'm thinking of cannibalizing the factory air conditioning out of a small SUV to cool the space.

Here's my plan, please tell me if it's too far out there or if you have any suggestions:
100 watt Renogy solar panels (suitcase style), golf cart batteries for lighting and small power needs
13hp Honda GX390 engine (estimated 8.5hp on woodgas) fueled by a downdraft gasifier
Belt drive to turn an automotive alternator to recharge the 2 golf cart batteries on cloudy days
Belt drive to also turn AC compressor
Mount the in-dash AC in the exterior wall like a window unit

I read that automotive air conditioners are rated at between two and five tons of cooling. I was shocked at the output but after reading more, it makes sense. They are called on to quickly cool a small greenhouse. My space is 8'x20'x9.5'h (high cube container) = 1,520 cubic feet. No windows.

I used Insofast foam insulation panels on the walls and ceiling. The roof is painted white using a NASA spinoff ceramic coating.

Yes, I know I could use a window unit to cool the space but I always want to learn new things.

Tips? Concerns? Anyone with related personal experience?

This is along the lines of something I am interested in doing. I'm going to try a brushless DC motor with solar, but the same idea. I'm thinking of going with a kit for a Ford Crown Victoria, or similar in the sense that it is a fleet vehicle with great parts availability and affordable. They have kits for around $200 - $300 which would also require a certain amount of accessories beyond the basic kit like the condenser, evaporator, hoses/hard lines, pressure sensor and such. Ideally a donor vehicle or a junkyard can provide serviceable parts as it gets costly buying everything new, and you mention using a donor SUV which is handy.

I figure it should be great for cooling something at the size you are using since you can have options with insulation. I think the restrictiveness of the system stuffed under the dash of a car, plus the inadequate filter setup isn't the best unless you have free access to the parts as in your case. A wood or sheet metal box could be fashioned to hold the blower motor, blower controller, and filter. Make a drain pan for the condensate. I'm going to look for a decent quality house filter of a common size like 20" x 20" which should be an easy upgrade to the vehicle setup. I'd imagine heat would come from a different source so the blend door and actuator aren't needed. If using a vent I wouldn't trust an old actuator to work for long. All that's really needed is a thermostat and a switch to power it.

You can use a thermostat made for controlling car AC. You can find universal ones or certain models in the 80's and earlier had a knob and copper temperature probe to control the pulley clutch. It really depends on what vehicle you get things from if you reuse the car setup. It might not work stand alone since cars for a lot of years now have everything tied together with onboard computer systems. You could try a cheap Arduino controller to run things like I'm investigating, but it doesn't have to be complicated. I'm also looking at eliminating the clutch with electric drive, but yours looks like it will work well with the AC clutch and alternator combination.

You can also lengthen the lines to move the noise of the motor further away. I think they have formulas online for lines of certain lengths and diameters needs X amount of refrigerant and oil. I wouldn't go crazy with it but an extra 25 feet and a little hut to muffle the noise, or at least moved to the opposite end of the container from where you work could be an option. Put the condenser with its cooling fan out there with it and run the evaporator lines and controls inside just like central air in a house. Here's a little bit of inspiration in the form of a repurposed blower motor:

Was guessing you didn't have enough power.  Quick google puts a 4 ton compressor at 14,000 watts.  There are 746 watts in a hp.  Quick math puts it just over 18 hp needed to run a 4  ton compressor.(chose 4 simply because it is the most common one I run into in the ag community.)  So you will likely need 3 engines of the size listed to power it.

There are basically 3 types of automotive AC systems out there.(actually about a dozen but they can be summed up in those 3 mostly)  1.  Expansion valve type used mostly in older system.  2. clutch cycling orifice tube type.  3. variable displacement.  You might want to study variable displacement to see if there a way to control it to keep the compressor in a low use mode.  While i know they exist and have attended a few classes on them a decade ago I have never worked on one on a tractor so I can't tell you much more.  Clutch cycling orifice tube type is going to be your least function most likely.

Hi Todd,

Have you gotten anywhere on this?

Todd Turner wrote:I've been into biomass gasification for years. I'm also building an office in half of a 40' shipping container. I'm thinking of cannibalizing the factory air conditioning out of a small SUV to cool the space.

Here's my plan, please tell me if it's too far out there or if you have any suggestions:
100 watt Renogy solar panels (suitcase style), golf cart batteries for lighting and small power needs
13hp Honda GX390 engine (estimated 8.5hp on woodgas) fueled by a downdraft gasifier
Belt drive to turn an automotive alternator to recharge the 2 golf cart batteries on cloudy days
Belt drive to also turn AC compressor
Mount the in-dash AC in the exterior wall like a window unit

I read that automotive air conditioners are rated at between two and five tons of cooling. I was shocked at the output but after reading more, it makes sense. They are called on to quickly cool a small greenhouse. My space is 8'x20'x9.5'h (high cube container) = 1,520 cubic feet. No windows.

I used Insofast foam insulation panels on the walls and ceiling. The roof is painted white using a NASA spinoff ceramic coating.

Yes, I know I could use a window unit to cool the space but I always want to learn new things.

Tips? Concerns? Anyone with related personal experience?

Todd, do you have the gasifier up and running?

Clever concept.
Pity about the operation.
Would an electric reverse cycle aircon. work?
They are very efficient, would your power needs be less than the automotive system?
I see they are rated ar 2.5Kw through to 10Kw, which may work for you.