Solar A/C, Electricty, and Hot water

[sid10]

This is a test to see if there may be some interest in an idea that I put out on the net a few years back.
What I propose is a solar powered device that will use heat from the sun or the earth to boil or vaporize a
refregrant gas to produce mechanical motion through a horizontally opposed two cylinder compressor. One
cylinder being twice the diameter of the other. The smaller of the two is spring loaded to return the piston
assembly to the starting position. The piston assembly is say a two inch piston and a four inch piston. The
assembly is also equipped with several large high strength magnets positioned on the connecting rod between
the two pistons. The cylinder assembly of the machine has a Field coil located at the midsection of the two cylinders.
The small piston's cylinder is equipped with two check valves one lets the working medium in the other out.
It is also equipped with a water cooled jacket. This jacket is strictly used to help cool the refregrant gas to
the point of liquefying it. The larger piston's cylinder is equipped with two electric solenoid valves, one allows
working medium in the other out. A pressure switch senses when the correct operating pressure is reached
at the heat collector and opens the inlet solenoid valve that allows hot high pressure gas  into the larger piston chamber.
This will force the piston down it's cylinder loading the small piston's return spring. At the end of the stroke of the
small piston a proximity switch will sense it's positing and close the inlet solenoid and open the exhaust solenoid
of the large piston. The now spring loaded small piston pushes the large piston back to the start point.
This causes the now not quite as hot expanded gas in the large piston's cylinder to be moved through piping that is
connected to a heat exchanger that is between the two pistons. Water is the heat exchange medium. This is the
hot water portion of the machine. The outlet of the water heat exchanger is connected to the inlet check valve of the
small piston's cylinder. Another proximity switch at the end of the stroke of the large piston starts the process again.
This back and forth shuffle will cause the magnets to pass through the center of the field coil. As we all know when
a magnetic flux cuts across the wires in the field coil a current will be produced.  This is the electrical portion of the
machine.This shuffle will also cause the small piston to pressurize the gas in it's cylinder and push it pass the
exhaust check valve into a receiver that will hold the now medium pressure cool gas until it reaches a point of being
of sufficient  pressure to force it through a orifice tube into an evaporator coil. This will cause a marked loss of pressure
A fan will move air across the coil and cause the low pressure gas in the coil to absorb the heat in it.
This is the A/C part of the machine. Think of the water heat exchanger as the condenser coil that sits in the front of the
radiator of you car or the condenser of the air conditioner that sits outside your house and the evaporator coil is just
that just like the one in you car or the one in your house.
So tell me what do you think? I have a couple of sketches of the set up and will post them as soon as i can figure out
how to save in a format that is allowed here.
Sid

[darbee63]

Not a bad idea, and completely workable!

Years ago there was a company that built a solar water heater called "the cricket", that was similar in theory.
They were built for remote places that didn't have electricity for self sustaining hot water for showers. It was designed on a tube within a tube setup, and didn't use refrigerant. Instead they used something like a solution of 10% denatured alcohol and water solution for the outside heat transfer solution, and to prevent freezing in cold climate areas.

Myself I've tossed around the same theory as you with refrigerant. Something along the lines of an old RV or motorhome ammonia refrigerator, but with a newer refrigerant.
But mine would be completely power free and use only pressures with expansions, and condensing being the only mechanical parts.
Then completely reverse the process for summer time cooling and and water heating. In winter for water heating and radiant heating.

Being hydronics, refrigerants and mechanical building are my specialty. It "IS" completely possible I can tell you that much for sure.  It Might take a 2 stage setup with 2 differant refrigerants to achive the desired heat transfer range for condensing and evaporation, but again on the narrow band side of it, it wouldn't be that hard.
But good ole money to build multiple applications and test models is my biggest hinderance like most other people garage testing. Especially the way copper and stainless prices have skyrocketed lately.

Like to see or hear more about it, what I'd like even more would be to be part of a joint venture build and installtion R & D team to build, market and sell these  energy savers. I have a feeling some big name appliance, refrigeration and water heater companies wouldn't be happy, because you'd knock 3 differant proprietary systems completely out of the market, who make billions if not trillions fabricating, marketing, selling, and installing systems that are basically using the same technology we had since 1950.

Being in the midwest, kind of does have its advantages when dealing or testing opposite sides of the weather extreme.
Currently working on plans for a solar water heater now, it'll be basic no tube within a tube setup (again the money issue prevents me from testing multiple setups) But I'm quite sure my design and setup will out perform some of these setups floating around out  there now.
I probably won't complete it until summer. But I would definately like to hear more from you or other people on this.

Thanks and goodluck

[Koen1]

Yes, it is a nice idea and seems completely practically and commercially viable.

I seem to recall reading something about that "cricket" device darbee63 mentioned,
and if I recall correctly it was indeed quite similar.
Don't know what happened to that.

But it's a good idea, sid.
It fits in the same category as solar-furnace powered steam-turbine desalination powerplant combos,
also a very usefull combination of several quite straightforward technologies, also powered by the sun.