Question: why is it that electrical engineers have not used the existing electrical power to run available AC motor generators to generate new electricity in the country rather than looking for new dams for generation of hydro-electric power

Kamal Bhattacharya answered on 23 Jan 2017:

This is a great question. I want to abstract the answer out a bit. The problem is this: you have excess energy and you could feed this into an AC motor that generates energy, which produces excess energy that you could feed back into the motor and so forth. This sounds good in principle, but the reality is that you lose a bit of energy in every step of the way due to heat dissipation. That means the input energy becomes smaller every time through this cycle and smaller even more. That doesn’t mean one cannot do it, but its simpler and cheaper to generate more energy at once than to do what you suggest.