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Electric Motors/Electric motor to turn generator head


I am interested in producing my own electricity, either grid tied or off grid. I have found a generator head on Ebay and it needs 1800 rpm or up to 40 hp in order to produce the KWH needed. I will list the specs at the end. My question is what type of electric motor could do this? Could I start the motor off a battery pack, and switch to the electric the head produces? I also would like to know the best safest way to do this so I don't burn up, blow up or kill someone who is working on the lines. I was told it would need a rectifier, diode so it wouldn't back feed the head and I can get a transfer switch hooked up as well.

Jessie,  you can produce electricity but I am not sure where you are going with this.  You want to drive an AC Generator with an AC motor which would make this what is called an MG Set,  

Most of the time an MG set will use an electric motor,  AC<  to drive a DC Generator to power a DC MOTOR.

The DC motor has different characteristics than an AC motor, low end rpm, torque so on,  so that is why they do that.

Then to drive an AC generator with an AC motor,  might be to drive say a 400 cycle generator compared to the normal 60 cycle power,    it is used for high speed tooling mostly.

You Could possibly RUN THE MOTOR   [the driver] off a battery bank,  but it would be one hell of a battery pack to get to 40 HP.

I am thinking you want to CREATE power,  electrical power,  but this setup is not going to get you there.

Remember E=MC2    

Energy is not created it is simply changed in form.

If you powered the driver with batteries,  the motor would spin the generator, the generator would produce power,  but you gained nothing,    the motor will not just start and keep running it needs constant power to keep going,      

If you tried to feed the driver with the generator [the driven]  then you would have a circle with no excess to use for anything else.

The last part about protecting the grid  is correct,   you would need some sort of blocking device so your power does not back feed into the grid and do as you suspect,   and that is not a problem,        but the concept is.

Don't stop working towards it,  you need to do a little reading on just basic DC electricity to start with.

Most people don't [and reasonably so] understand that an electric car,  although it uses electricity starting with batteries,  still uses some sort of coal, nuke, gas, power to CHARGE THE BATTERIES,   that is why they have to be plugged in,  which has a line right to the nearest power plant whatever kind it is.

You need to find a power source,  say water falling like a water wheel  to turn the driven generator,    something that already exists or could somewhat easily be converted,    

Using the electricity you produce to power the driver that turns it is a zero sum game or in most cases a negative gain.

This is the major road block for anyone wanting to do this,    

Some use solar,  some use wind turbines,   some use  and this is a terrific idea   water that drains normally in a house to turn a water wheel,          it is still complex,      

Now if you are just looking for backup power  that is something else, and I would suggest a natural gas engine to turn your driven load [generator]

Then it becomes a battle of efficiencies,   where you get the most power from a given source be it natural gas, wind, solar, so on,       

Do some reading on basic electricity,  some basic physics  and that will get you on a more realistic path.

It is people like you who study and find answers, most all start out somewhere wrong,   but with some tweaking they find a way,        

When I talk about efficiencies,  here is a rough example,     for an internal combustion engine, a rough eff of 45% would fit,    where an electric motor can run 90% plus,  

This means that the electrical power is almost at 100%,  where a sloppy internal combustion engine wastes nearly half  just in the conversion from gas or whatever fuel into some sort of turning or torque energy.

While technology has improved internal engines,  as well as electric motors,  those figures I gave you are rough,  but generally speaking,  electric motors are much more efficient than internal combustion engines.

Sorry to bring the bad news,  I applaud you thinking,  but to do what I think you want is not going to work without a huge bank of batteries,   and a power source to charge them,  if you charged them with the driver  then again,  it is a circle   without any left over power to use for other things.

Read up,  do some Internet searches [be careful there are some bogus claims and sales out there don't fall for any of it, if you find something that catches your attention,  let me see it first and let me investigate] but I really think your best approach at least now, is maybe the library.

Once you get the hang of how power [energy] is really not created, but changed,  you will be way ahead of most.

There is a good website to start with,  and has references to more material,  from there you can get a clear understanding of power, energy and how to deal with it.

Keep at it,  if it was as simple as buying a generator and making our own power, we would all be doing it,  but is not the case,  solar is getting smaller,  wind is becoming more popular, combinations are working, and new ideas come along all the time.

Stick in there and remember knowledge is the key.


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Three phase/ AC DC single phase motors, controls, any problems or failures, motor installation, performance issues, connections. All other electric motors/gearboxes/apparatus. Specialty repair concerns, obsolete motors and solutions. Other mechanical or specialty equipment. See my profile under Home/electrical at this site


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