AC Engine Alternator Conversion Project

Do you realize that 1 MegaWatt is 1,341 Horsepower!? That is at 100% efficiency! Large alternators generally have efficiencies around 30%. If you plan on using a motor that was not designed as an alternator, expect to drop that efficiency to around 15 or 20%.

This means that to drive this alternator, you are going to need an ICE between 3000 and 6000Hp! You are going to need a LOT of biofuel to to run such an engine!

The alternator converts the rest of the energy into heat, so it must be physically large enough handle that heat, with appropriate cooling. At this kind of power, the alternator must generate its energy at high voltage. At 1,200 volts, it would have to produce 833 Amps. Even at 12,000 volts, it would have to produce 83.3 Amps. We are talking about extremely LETHAL energies.

I don't believe it is realistic to expect to save any money by doing this yourself, and live to tell about it. A MW is enough energy to power several hundred small homes: this requires a large team of trained personnel in a variety of specializations.

Hello, I'm just a guest reading the CR4 for the first time & thought it seems all the Guru's herein are always saying don't do that ?

Why don't the guru's ( with their superior knowledge ) tell us how to do that ( not just don't do that & go hire some other Guru ) - it would be a bit more helpful to the lost and learning.

After all , If the questioner had asked the question, in the wrong way or ask the group how to - well then saying specifically why don't you build a new machine and this is the way it would be built - just seems more polite and helpful.

Most likely good I'm New since I just pissed off all the Guru's.

Pissed off no, but did you understand fully the answer......I think not and that is really sad!!!

If such things were so easy to achieve, then many people would have done it already, don't you think?

Its sad just how many people post such requests on CR4, without having the slightest idea on how to achieve what they want to do and cannot even do simple math to find out the power levels that might be needed......as in this example......its either very funny or very sad.....search out your own thoughts on that last point, laugh or cry!!!!

For over 50 years I have been a 'do-it-yourself'er, and am very accustomed to using things for purposes other than their original design intended. I certainly encourage others to do the same when it is appropriate. But that is when we are dealing with a few hundred Watts or less, maybe up to a few kW. But when we are talking about 1-5 Megawatts, I'm very concerned about efficiency and especially SAFETY.

I repeat: I don't believe it is realistic to expect to save any money by doing this yourself, and live to tell about it. A MW is enough energy to power several hundred small homes: this requires a large team of trained personnel in a variety of specializations.

Dear Sir,

As I said thank you and good day.

Joe

Hello All - Again,

Mr. Warner, your right the power level is High. And I think your right the way is to not use something already built . I would like to to find proper drawings of a 1 MW alternator system to build myself, or as it were have my help do so. Proper help would be great as well, your in Calif. so if you have an Idea whom I might contact , let me know.

Guest, no matter their conversation roughness , the Guru's are hopefuly giving their best ideas and not trying to create billing hours for the industry. I know I would in these forums tell anyone whom might me for ask the correct answer, just the facts.

Join us friend and add content., Content that we can all learn from & perhaps the Gurus will add specific "how to" answers also.

Thanks Fellows,

Joe

@ the 1MW size: try looking at synchronous AC motors with a wound field; a PWM DC excitation should be ok for voltage control

output will be 3ph; freq dependant on RPM of shaft (if this matters, you'll need a precision regulator)

plan on ~ 80% conversion efficiency.

You might want to check out the wind power industry as a source for your generator. GE's website lists a 1.5MW wind tower using an asynchronous AC generator. With some quick searching, I bet you can find something closer to the 1MW you are looking for. The generator and drive train are mounted nicely to a bed plate too. Maybe you could find someone who is decommisioning their old 1MW wind tower and selling it cheap.

Are you using cow/farm waste for your methane source? I just saw a TV show where a farmer built his own methane processing system that fuels an ICE/generator, but it was much smaller than 1MW. It was enough to run his farm. I can find the name of the show if you are interested.

I love a challenge too, but with little knowledge and no expertise in this area, I'd look for a used generator to start with. Why reinvent the wheel? After all, your goal seems to be to net the most power from biofuels, not necessarily to design a new generator technology. There are teams of engineers and designers working hard at that around the world, with a lot more resources than you or I have.

Hello Fellows,

Thank you for your input.

Side, I will be looking for the synchronous AC motors with a wound field that you mentioned . We have a large granite industry here abouts and the possibility of the same is there , or so I have hoped.

Greasy, I have heard about the GE power plants for the wind industry as we sell R.E. equipment at my office too. I just don't know of any in my area and certainly none that are going to replace anything that large. This is the reason I've been looking at conversions as compaired to buying new . I have new equipment at my order pad, if needed, it just cost lots more , and I'm cheap. Building new is a real possibility.

We are in NE Georgia so not so many Cows in the hood. Dairy farming locally closed up shop 2 years back, but we have the shorter meaty versions : Chickens. When one compairs the 2 waste streams for fuel, you find Chicken Power is better under the right conditions as the methane is much higher in production rates and transfer truck loads of litter are available for the delivery cost , sometimes still free .

Thanks for the offer on the cH4 production contact, it would be good to learn 1st hand , rather than just from class room text and good to hear from someone close by.

What I want is to build community power systems that my company can put out when needed and that can be intergrated , grid tied, or not and 1 MW is the minimum to think in terms of. 5 MW would be better from a commercial stand point as the power to cost ROI is more on target; but buying the equipment new, is well off the charts for medium investment abilities.

Joe