What's wrong with this

[ramset]

....................

[Floor]

@ MarkE
  I get it.
                peace
                    floor

[Floor]

Thanks
           for the support ya all
           and the timley reminders last night
           Right on.
           
            And thanks for the offers, but homey don play that s**** unless he has to.
            No one here at OU was connected to the suicide event.
                                             

                                    peace = no war
                     floor

[tinman]

Are those blue berries blueberries???
    Now your getting close,but no energy is required to condence this gas into fluid.
OK, so it's your idea that you are going to condense gas into denser liquid so that you can sink, and that when you make the transition in that direction, you will rely only on passive cooling to do so?

There maybe a 2 to 3 degree C temp rise during the gas to liquid transition, but what dose that matter when your in a sea of cold water. Once the vessle reaches the sea floor, the transition is reversed, and liquid once again becomes gas. This increases the vessel's displacement area, and also decreases its weight-and up she goes again.

[MarkE]

There maybe a 2 to 3 degree C temp rise during the gas to liquid transition, but what dose that matter when your in a sea of cold water. Once the vessle reaches the sea floor, the transition is reversed, and liquid once again becomes gas. This increases the vessel's displacement area, and also decreases its weight-and up she goes again.

I think that you may have overlooked that the energy to reinflate the gas containers is at least equal to the energy removed from the gas by the sea water heat sink.  Put another way, you can calculate the energy required to expel some amount of ballast sea water as the product of the mass of that ejected ballast and the distance to the sea surface.