Substitute a gas motor with electric motor

[Charles Doyle]

I'm sure that this has been posted before but...
I want to substitute a gas motor in my 12kw Generac home backup generator with an electric motor 48-volt 4hp@4000 rpm series.. I would run this electric motor from the grid and power my home from this newly design generator.

 

[Jeff Rosenbury]

Why would you want to do that? Did you lose a bet?

 

[Charles Doyle]

Correct me but the power consumption for a 48v motor that can propel a 12kw generator consume less power, I would thing 375 kwh/mo in turn costing me about 75.00 per/mo.
This would be a big savings

 

[russ_watters]

So, I'm going to guess this is an attempt at a perpetual motion machine, but leave the thread up until confirmed. Trouble is, if you connect a 3kW motor to a 12kW generator, it'll just output about 3kW, and at a lower efficiency (say, 3.5kW input) than if you just used the mains electricity directly.

But yes, we do get this question disappointingly often.

[Edit: suspicion confirmed. Sorry, but the question is answered and we don't discuss perpetual motion here, even for debunking. Thread locked.]