That compressor looks like this one, for less than half the price...
http://www.revoltevc.com/climate/cooling/compressor/sierra-02-compressor-151.html
Edit: Looking closer I didn't realize it came with the control box. The one above is just the compressor.
Same company as the link you found.
http://www.revoltevc.com/masterflux-sierra-02-0716y3-system-kit.htmlInteresting read .....
Details
Though we sell electric compressors that run on 12VDC, they are limited to use for small cabinet cooling, refrigeration, dehumidification, and other specialty tasks. The reason is power consumption for air conditioning and power conversion efficiency.
An overview of the problem
Our largest SIERRA-06 series compressor kit provides about 1.5 tons of cooling running at full power and under optimal conditions, and draws up to 2kW of power to do so. It is immediately not operating on the same level as most automotive air conditioning systems, which range somewhere around 2-3 tons for a small car, and sometimes greater than 6 tons for larger SUVs. This cooling capability is adequate for our primary market in electric vehicles due to the smaller total heat load, that is, countering only the sun's radiation, but not factoring in a hot engine and exhaust system. Even so, the DC kits we offer are best used with as much "help" as they can get -- window film, light-colored paint and interiors, window shades, and so forth.
Reducing the voltage
As the voltage decreases, more current is needed to produce the same power. Below 48V, the limitation of the compressor design sets in: The terminals physically can not handle more than about 50-55A. As a result, the lower-voltage models run with reduced performance. At 12V, the SIERRA-02 is capable of a little better than a fourth of the performance of the high-voltage models, and still draws a relatively large 50A current to do so.
In summary
Even if it were possible to get the same performance as our high-voltage units at 12V, you would need about 200A to do so, which would require a very large alternator and massive copper wiring. Ultimately it would run at a greater cost of horsepower from your engine, due to losses in the alternator itself, and in the motor and controller. A standard engine-driven automotive compressor skips these mechanical-to-electrical and electrical-to-mechanical conversions, making it far more efficient and lighter overall
Special situations
We have sold 12VDC systems for solar application, as well as some specific solutions. If you feel as if your situation merits a 12V compressor system, we can certainly provide you with one. Please give us a call or consult with us before you order, because, unless your specific situation is very unique, it is unlikely that you will be satisfied with its performance.
This system package includes the compressor, controller, the controller harness, vibration isolation mounts, and the optional manual control device.