Total energy required to turn the two turbines to produce 2 joules each should be 2 joules each. anyway in the real world all the energy would be lost to heat and friction. i've ponder upon this question few years ago. placing a magnet under a spring, place it vertically. and in a vacuum container. if you let the spring bounce up and down. it will bounce forever as there is no air resistance. however, when placed an EM coil around it to create current when breaking the Electro magnetic flux, you will see that the oscilation will be dampened.

not to be sexist, but i'm impressed a girl would think so deeply into physics. respect