Originally posted on sciforumsDOTcom by me (DRZion):(adsbygoogle = window.adsbygoogle || []).push({});

So I came up with a scenario which is simple enough for anyone to understand.

You take a fluid which is liquid at room temperature, but freezes to a become a solid denser than the liquid.

This is done to any amount of liquid at the surface of a pool of liquid. The energy required to freeze this liquid is x.

Now, the energy released as the solid sinks is just (Ds-Dl)vgh

where

Ds is density of solid

Dl is density of liquid

v is volume of the frozen solid

g is gravity

h is height

Since x is a constant and energy released scales with depth of the pool (h), there must exist a depth where x < energy released.

When the solid melts the temperature of the pool decreases, but it can draw this heat from the room, which is at room temp. Hence ambient heat -> gravitational potential.

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# Reducing the entropy of a closed system

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