Heat exchangers makes potential energy for free?

[Low-Q]

I have been thinking a bit on heat exchangers. Below there is a picture of a heat exchanger that is using both a compressor and a decompressor. Both compressors are made of high efficiency gear pumps.

I have a theoretical question:
If the compressor is compressing the gas inside the left hand pipes, this pressure could start to run the other pump, just like the pneumatic power tools are working. If we loop this circuit and let it build up high pressure on the left side by running the compressor, and let it be less pressure on the right side by temporary resist the decompressor. Then we can start the decompressor by attaching it to the compressor axle. Now these two compressors will push and pull each other so it will only take the energy which is required to power the little losses in efficiency of the compressors. But the potential temperature differences will build up between left and right. This potential energy should be far more than the power needed to run the compressor and decompressor - as they together are a closed loop that reduce the need of power consumption. I assume we can harness the potential temperature difference almost limitless, and regardless of the power needed to run the compressors. Lets say it requires 100W to run the compressor motors, and in return the potential energy in the temperature can provide 1kW energy, it is beyond doubt that this system is over unity?

What do you think? Is it more secrets to the heat exchangers than the industry are willing to tell?

Vidar

[Low-Q]

It is the same pressure at the compressor outlet and the decompressor inlet. It will therefor not require energy to run the compressor or the decompressor. The result are hot and a cold areas with great potential energy that will power these compressors:)
Anyone?

[sparks]

   You got heat you got power.  The power people know this and could have converted to heat engines a long time ago.  This krap about having to have a high differential in temperature to make a heat engine run is bullshit.  You need the molecular motion period.   Tesla had the neatest idea.  Take a vessel and sink it into the bottom of a lake.  Through the side of the vessel you open up a hole.  This hole then communicates with the interior of the vessel which has a tube rising to the surface.  The water pouring into the vessel is caused to run through a turbine.  The turbine drives a generator that splits the water into hydrogen and oxygen gas which drifts up the tube for latter use.  Your idea got me thinking what if the turbine ran a vacuum pump.  The vacumm pump makes the entering water boil because of the reduced pressure. The vacuum pump is above the water level so as the vapor rises and is discharged by the vacuum pump it condenses immediately and collects in an elevated resevoir that returns to the ocean through another turbine that ships the electricity to shore.  The water boiling down in the ocean floor extracts heat energy from the ocean this is what allows it to stay a gas.  As it rises up the column it remains a gas until it hits the relatively highpressure at sealevel.  hmmm

[Low-Q]

It is the potential difference that can be converted to kinetic energy. The more potential difference the more kinetic energy. Could you make a drawing of the turbine idea you got?

[Cherryman]

Hi low-q and Sparks

Here they make ice from vacuum : http://www.youtube.com/watch?v=pOYgdQp4euc

Let say you have a heat-source (Sun, fire, .. )
So i was thinking, use the heat to warm up a cylinder filled with an expanding substance when heat added, let the expansion of that cylinder pull a vacuum in another cylinder filled with water. Now you create ice from heat!

Putting a peltier in between gives you also electricity. 

http://www.youtube.com/user/YbborNetsrek#p/a/u/0/e4w86FZwdJE