I had a crazy idea some time ago, about using a small, cheap solar collector to produce superheated steam (and my father and I did build the device described up to this point and it works fine) and then use a venturi to trade the velocity of escaping steam for volume of air moved (inject steam via a fine pitot into the opening of a pipe so that outside air is pulled into the pipe) [ed: better yet, use the steam jet to create a vacumn in the exit pipe on the hot side and avoid the temp increase of the steam on the inlet side] and then direct that into a Hilsch Vortex to produce hot/cool air for house A/C.

I would guess that back pressure at the entrance to the Vortex would limit the incoming air volume excessively or that the increased temp of the air (due to the steam injection) would negate any cooling gains on the part of the Vortex or some such other problem would prevent it from working. BUT, I haven't been able to find any proof that the idea is unworkable. Please help put my mind at rest or send me a million dollars to finance a prototype. (GRIN)

The nice thing would be: No moving parts other than the water and the air and the collector (sun tracking), automatically starts when the sun heats it up, super low construction cost, almost zero operating cost (only maintenance and water supply). The potential inefficiencies are offset by the low (zero) cost of water and sunlight.
-- James Newton, Jul 31 2002

For those who (like me) are wondering what a Hilsch Tube is. http://www.visi.com/~darus/hilsch/
[angel, Aug 01 2002, last modified Oct 21 2004]

Solar Steam Cooling website http://techref.mass...href/other/spac.htm
More information on the idea. [James Newton, Aug 02 2002, last modified Oct 21 2004]

Steam can be used to cool! http://www.atsfry.c...ssenger/pass_ac.htm
Old railroad steam powered AC using simular idea [James Newton, Oct 04 2004, last modified Oct 21 2004]

Check out this cool use for steam injection! http://www.pursuitd...ics.com/default.asp
Imparting steam momentum to a stream of water. [TIB, Oct 04 2004, last modified Oct 21 2004]

The Hilsch tube works by essentially compressing some of the air and decompressing the rest, which in turn raises the temperature of the compressed air and decreases that of the decompressed, so that the heat from the hot tube may be sinked. Adding more heat to the system by whatever means would be counterproductive to the goal of cooling the thing down. The necessary component in this case is a supply of forced air somehow, which from re-reading, I guess you already understand. Whether or not a venturi would be enough to do the trick would be the sticking point. Interesting reading nonetheless; I hadn't known that the Hilsch tube existed until now, so thanks for that...
-- RayfordSteele, Aug 01 2002


I (predictably) like this. Have a solar-powered steam-filled croissant.
-- angel, Aug 01 2002


The most useful places for this, methinks, are where there is an ulimited supply of sunlight; unfortunately, said places are usually rather short of water. Otherwise, an excellent idea.
-- DrCurry, Aug 01 2002


See www.atsfry.com/Passenger/pass_ac.htm The railroads used steam to create a water based a/c system. Steam provided the power for an ejector to create a vacuum, lowering the boiling point of water. This allowed a higher percentage of water spray to evaporate in a low pressure chamber, leaving much colder water to circulate in the cold side of the system. I'm not sure of the energy efficiency of such a system as it seems to use electric motors for blowers and pumps.
-- blane69, Jul 24 2003


Wouldn't it be better that the steam drives a turbine whose shaft drives a compressor?
-- rpardell, Sep 05 2003


Sure, but turbines and compressors add cost. If initial investment isn't an issue, replace the solar steam unit with a Sterling heat engine and avoid the water use and danger of steam altogether.
-- James Newton, Sep 11 2003


You could use superheated air from your solar array to heat an ammonia-cycle refrigeration system for use as a house A/C. See the link to Pursuit Dynamics for one of the best ideas related to steam that I’ve ever seen. +
-- TIB, Sep 11 2003



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