lets say we have an inflatable at the bottom of a tube, which is going to be infinitely deep for now
there is a weight or resistance attached to the inflatable
now lets say that it takes x amount of energy ( we use an electric air pump that draws air from the bottom of the tube) to inflate
the inflatable fills with air and inflates, a rope is tied to the inflatable, and wrapped around the crank of a generator
as it goes up, it generates electricity
because it is infinitely deep, it will keep going until it has generated more electricity than it took to fill it, and enough to allow it to deflate, and sink back to the bottom
how could it fail?
-further down, harder to inflate due to pressure from water
-would take more electricity to inflate something that deep than it would produce
-energy to get air down is same or less than what can be gotten out of it
-energy to overcome pressure is equal to or less the distance the float would be allowed to travel
so basically its a relationship between pressure of depth and distance the float would be allowed to go
this would only work if it was an actual tube where air could be drawn from underneath, and wouldnt have to be taken down
maybe its not as hard to figure out for anyone else, but its an idea ive been tossing around in my head
The rope wrapped around the crank is going to eventually weigh too much for the inflatable to continue carrying upwards, as it rises it just keeps adding more weight to the amount it is lifting, and eventually will be able to rise no more.
But what happens if you go the other way, and drop a rope-tied rock into a bottomless pit?
;D half of the forum members (no exaggeration) had this or a variant of this idea. Keeps recurring here in this section, just dig a bit and u will find hundreds of math calculations and hot discussions :)