In the Rus region since the Soviet times there was a small hydroelectric power plant, feeding nearby villages. Now, of course, for the Moscow region, this is a drop in the sea, and the local authorities decided to make another, but there is simply no other suitable river. Therefore, the project was ordered for several lags: a mine 90 m deep, where water falls, the bottom of a turbine with a generator that gives current to the network, and at the same time feeds the pump that pumps the water back - up. Coincidentally, our neighbor, a well-known engineer, was talking. He squeezed slightly and said about "perpetuum mobile". The foreign words did not understand, he said, “This is the eternal engine.”
- Well not eternal, you need to lubricate bearings, change brushes.
Have you heard of the law of energy conservation?
Is it federal or regional law?
Hearing that it was not a Russian law at all, the engineer was kicked out so as not to spoil the atmosphere.