Refrigerated cooling without electricity

Yes, correct, refrigerated cooling without electricity! (almost if you use a fan)
before the "how too" let me ask one favour, if you make a commercial unit I would like just one dollar for each unit built, not too much to ask I'm sure.

Here's how:

Those of you who have a mobile home/caravan etc. will know you can have a refrigerator that runs on LPG/Propane gas, they are silent and work well, in rural Australia the early refrigerators used kerosene for fuel, these use a simple system comprising a heater tank and a condenser, heating the tank vaporized a gas, (usually ammonia) the expanded gas was forced through a valve with a tiny hole, the pressure liquified the gas and presto, sub zero temperatures, this liquid ammonia passes through the condenser inside the refrigerator soaking up heat and becomming a gas once more, passing to the heater tank to begin the process anew.

Now, scale up the elements, place the heater tank on your roof, the condenser inside your home and the pressure valve in between, now boost the airflow through the condenser with a small fan, you can skip the fan and rely on convection only if placed near the celing, (warm air rises, cold air falls)

The parts are easy to obtain, (pure liquid ammonia is dangerous and toxic!) anyone with basic metal work skills should be able to knock their own up in less than a week.

So is it efficient? well not as much as a compressor driven air conditioner, however unlike standard air conditioners this one can be left running constantly for free!,
(have a shutoff valve for winter) built properly it should last for many years, kero refrigerators lasted for more than 20 years except for changing the wicks. The hotter it is outside the more efficent the unit becomes.

So there it is, I built a small "test" unit out of parts from a discarded caravan fridge and it would keep a small bedroom at 25 degrees C or so when the outside temp. was 38 degrees C or thereabouts using a 1 square metre (thats 3 feet by 3 feet approx. for you Americans) black steel plate as a solar collector.

Remember the power companies are NOT going to be impressed! so market the first units for caravans/mobile homes, rural cabins infact anywhere there is no power, then start with tourist areas and travel Inns, tourists/holiday people will begin to want them at home, and before the power companies know whats happening bingo! free cooling!