Perpetual motion does exist, but the very reason of it's existence(the principle of entropy would encompass all the laws of nature involved) is also the reason why it will never be harnessed.
Some people (like teszla) like to speculate about harnessing vacuüm energy. Again, this will never happen. All the energy we can harness is by definition the energy difference between several energy levels and since we don't occupy the lowest level and energy cannot flow to a lower level than the lowest level.....
You could look at the universe like a box of light bulbs of wich only a few are switched on. The energy difference between the bulbs that are switched on is less than the energy of the bulbs themselves. But if you would want the bulbs to emit the energy they hold, then they would have to dissapear so they couldn't emit anything no more.
Some people (like teszla) like to speculate about harnessing vacuüm energy. Again, this will never happen. All the energy we can harness is by definition the energy difference between several energy levels and since we don't occupy the lowest level and energy cannot flow to a lower level than the lowest level.....
You could look at the universe like a box of light bulbs of wich only a few are switched on. The energy difference between the bulbs that are switched on is less than the energy of the bulbs themselves. But if you would want the bulbs to emit the energy they hold, then they would have to dissapear so they couldn't emit anything no more.