I'm sorry, I don't think I understand what you mean by schematically. Could you give an example? The question is interesting to me and hopefully to others. Thanks for the discussion.
Thanks for your reply. I realized I missed one important contextual thing. The way to measure the "energy" present in that system would be to put the water through a turbine and measure the amount of energy generated. I guess that means gravitational potential energy plus the additional energy...
At sealevel, the water in the tank is just mgh so 1000 kg * g * 1m so about 10 kjoules.
Now if we pump air until it is 2 atm.
The potential energy of a compressed gas is given by the formula:
U = -nRTln(V2/V1)
But in this case it is not the gas that we care about but the water.
I can...