Has anyone every search Gravity and Heat as alternative energy sources?

[Douchebag McJr.]

Gravity is a natural force that pulls down, therefor it should be possible to get some energy out of it.

And heat is a free and limitless energy source, i think.

Has anyone looked into this???
If so what came of it?

[Pahis]

Yes they have. Water dams

[jeebus22]

Yeah, dams work off of gravity. And people have tapped geothermal energy.

[hrothgar]

The trouble is to get energy out of the gravitational field, you need to have stored it in the field before.

Think of dropping something. When you raise it up, you do work: you store energy in the gravitational field. When you release it, the field releases that energy, speeding up the object until it hits the ground (which then creates sound [energy], as well as heat).

So, to get energy out of the Earth's gravitational field, we need to find either something really high that can flow down, or some place really low that we can drop things.

Hydroelectric plants are the culmination of such an idea. The water's speed from flowing down a mountain will create the power.

The trouble with heat is that though it is clearly plentiful, one may argue infinite since the Universe does has a non-zero background temperature (and is infinitely big, as far as we know), to get usable energy from this heat means you need to cool down the Universe. This violates entropy, as it moves to a lower entropy state. By the 2nd law of thermodynamics, this cannot happen. Therefore heat is not a viable source of energy. It is, however, a method to transport energy (from a boiler through water to a radiator to the air in a room; but the heat [a form of energy] you get in the room is much less than the energy in the natural gas or oil burned in the boiler -- a net loss of energy).

[Brian S]

while gravity may pull down, it takes energy to push it up, infact it takes more energy to push it up then you get out from pulling it down. Heat is used all the time, in the form of Gasoline, coal, nuclear, etc.