Micro CoGen.

There is more than one 3-phase wiring config. and considerably different voltages can be obtained - Delta vs. Star. 2-transformer vs 3-transformer drop from transmission lines.

I think we can do a more thorough answer, but give me a bit to get it all presented clearly.

dieselgman

I thought you had a single phase motor turning a 3-phase genhead... that eliminates the voltage change issue altogether.

dieselgman

It may not be too difficult to turn out a stub shaft for that application... just a thought.

dieselgman

I am sure there is considerable variance between setups and different size towers but a typical generator requirement for them is 15kW and that is wired at 480v.

The conductors don't so much 'care' about the voltage as much as current but the two are related per Ohm's Law (E=I x R) - Up the voltage and thereby reduce the current requirement for a given amount of work.

In this example as I understand it, incoming single phase voltage will be 240vac and converted voltage (at the pivot) will be 460 [or 480] typical. Only half of the circuit will enjoy the higher voltage benefit - but better half than none.


dieselgman

Casey, I think you are basically right... but the boom wiring portion (likely 1/4 mile) reduces the current requirements and voltage drop if run at 480vac - at least for that portion of the run.

3-phase generally has available high-voltage (480) whereas single phase will only do 240. Higher voltage = less current requirement. You do get the benefit of only needing a single neutral lead for all three power legs with a properly wired 3-phase system. This is one reason most commercial wiring is configured 3-phase. The other primary reason is motor efficiency.

dieselgman

We purchased a couple crates of these some time back... good people to deal with. I have not figured out how to accommodate a second bearing with that shaft flange as supplied - as of yet.

dieselgman

Even Fairbanks Alaska has banned these things... but just another political football in my opinion.

Hydronic heat transfer to the buildings and hot burns is the way to go!

dieselgman

I am not able to locate any pricing information on their site... where did you find it Butch?

dieselgman

I just know that the commercial corn ethanol plants around here have been going bust! Without the government subsidy they likely would have never gotten into production in the first place. It seems that the inputs exceed to outputs... sadly. I hope that a small 55 gallon plant has much better economics, but I wouldn't bet on it. Maybe moonshine waste fuel heat inputs and by-products would cover the costs!

dieselgman

I wonder about your pumped "recirc loop" and how that would work with a tankless "on-demand" type of water heater.

Also, the variable temps feeding that tankless heater would require some serious engineering to achieve a stable output temperature - I guess 'second generation' means it has a very smart controller?

Off-grid hot water systems I have seen generally have not been too great with electric hot water heating, what is the heat source in your tankless unit?

Very nice schematic by the way! 

dieselgman

Well, we are glad to hear of your success! Most likely a sticky pump element or something along those lines. I'll check-out your old pump when it arrives here.

As far as 'de-rating' is concerned though, it will be valve timing that changes quite a bit. Something on the order of 20 crankshaft degrees difference on the exhaust valve from 8/1 to 6/1 specifications for the change from 850 to 650 rpms.

Best Regards,

dieselgman

I would recommend you price these at what their true value is to you... the rest is pure speculation. If we had them here, new in crates, we would most likely price them as we do the clone engines - that is calculated from landed cost plus overhead. We pay $250 per engine pretty much sight-unseen, add in shipping and handling, possible long-term storage and our business overhead, right away we have at least triple the original price in them (thus the $750 figure I threw out).

We have zero interest in Petter AC models, but from time-to-time we do special-order parts for a few folks who have these models.

dieselgman

Again... plenty of value to someone wanting air-cooled AND 3600 rpm... scrap value is $250 per and anything up to $750 per unit would be a reasonable offer (If you needed this engine style).

Value is completely relative to supply and demand... in this case RARE is a very bad thing. We buy and sell the old Listers in the hundreds - military AC twins are definitely not sought after. Find exactly the right person and you could ask almost ANY price...

dieselgman

AC2 is a bit rare... can be modified to variable speed but power curve not that great at slower speeds. Offer scrap prices and be safe, is there any competition?

dieselgman

Nothing wrong with a Deutz F3L until you have to locate & buy parts or do any major work... good find there! I used to own a F2L on a genset and it was a good performer!

dieselgman