Triskel power generation system on Distant Shores III

[Dockhead]

Originally Posted by a64pilot

. . . Likely your doubling the number of hours on the most expensive engine as opposed to putting hours on a less expensive generator..

Minor quibble:


A heavy duty genset is not really cheaper than a propulsion engine. My main and genset cost roughly the same, around £20 000 each.


A light duty genset is cheaper as an absolute number, but probably not per hour run, when you factor in the much shorter useful life.


And also -- it is more economical to run one item of plant twice as many hours per year, than double the plant for half the hours each, because TIME is a big part of the cost -- time value of the investment into the plant.



Just like it is -- obviously -- more economical to run one airplane twice the annual hours, than splitting the same number of hours across two airplanes.



So if you can do the same job with one engine, even if you have to run it double the hours per year, you will come out ahead in terms of cost, maybe way ahead.


One diesel engine vs two is also lighter, which can have a significant effect on sailing performance.


I think you are underestimating the strong points of this approach.


And one variant of this approach which I find very attractive for me (as someone who cruises in some extremely remote location, so needs more reliability than the average bear), is to use the main engine like this for primary power generation, driving some kind of very large alternator, but to have a light duty generator like the NexGen instead of a heavy duty generator like what I have. Because then the genset can be mainly backup, rather than prime power. That would save a great deal of money, weight, and space, compared to what I have now.


But I think with enough alternator capacity on the main engine, most cruisers could dispense with the genset. Other than those who plan to run air conditioning for long periods of time -- that's a very specific use case. Those folks will need a heavy duty generator.

[Kenomac]

Originally Posted by Dockhead

Minor quibble:


A heavy duty genset is not really cheaper than a propulsion engine. My main and genset cost roughly the same, around £20 000 each.


A light duty genset is cheaper as an absolute number, but probably not per hour run, when you factor in the much shorter useful life.


And also -- it is more economical to run one item of plant twice as many hours per year, than double the plant for half the hours each, because TIME is a big part of the cost -- time value of the investment into the plant.



Just like it is -- obviously -- more economical to run one airplane twice the annual hours, than splitting the same number of hours across two airplanes.



So if you can do the same job with one engine, even if you have to run it double the hours per year, you will come out ahead in terms of cost, maybe way ahead.


One diesel engine vs two is also lighter, which can have a significant effect on sailing performance.


I think you are underestimating the strong points of this approach.


And one variant of this approach which I find very attractive for me (as someone who cruises in some extremely remote location, so needs more reliability than the average bear), is to use the main engine like this for primary power generation, driving some kind of very large alternator, but to have a light duty generator like the NexGen instead of a heavy duty generator like what I have. Because then the genset can be mainly backup, rather than prime power. That would save a great deal of money, weight, and space, compared to what I have now.


But I think with enough alternator capacity on the main engine, most cruisers could dispense with the genset. Other than those who plan to run air conditioning for long periods of time -- that's a very specific use case. Those folks will need a heavy duty generator.

You really gotta shop around more for your generator I’m afraid if you actually paid that much. We just replaced a Cummins Onan 13.5kw generator including the sound shield case brand new including shipping and our 8 hours of labor for $14,000 USD. Your price of $26,000 USD for one half the size would be ridiculously overpriced.

[Kenomac]

Another point: When your naval architect designed your boat or anyone else's,
the weight and placement of the heavy generator was taken into account in the overall design. Remove it, then the boat will be off balance and won’t sail the same with 500-700 pounds of ballast now missing.

[Dockhead]

Originally Posted by Kenomac

You really gotta shop around more for your generator I’m afraid if you actually paid that much. We just replaced a Cummins Onan 13.5kw generator including the sound shield case brand new including shipping and our 8 hours of labor for $14,000 USD. Your price of $26,000 USD for one half the size would be ridiculously overpriced.

UK prices I'm afraid. Including installation.

[Dockhead]

Originally Posted by Kenomac

Another point: When your naval architect designed your boat or anyone else's,
the weight and placement of the heavy generator was taken into account in the overall design. Remove it, then the boat will be off balance and won’t sail the same.

Taking weight off, unless you do it in a way which upsets trim, or take it out from somewhere below the waterline such that you reduce stability, is all good, even on existing designs.



But that's not really relevant anyway because no one suggested removing an existing generator. I've already got mine, it only has 2000 hours on it so far, it runs great, and it will last longer by far than I will own this boat. I'm sure as heck not taking it out.



This is a theoretical discussion -- for new boat designs.

[Kenomac]

Originally Posted by Dockhead

UK prices I'm afraid. Including installation.

You’re unable to purchase a generator from someplace else and have it shipped to the UK to save $15,000 USD?? I didn’t know that.

Theoretically speaking of course.... aren’t most 500-700 pound generators installed below the waterline? I know our 1000 pounder is, it’s way down low, in fact... it’s right down there with the 1700 pound battery bank as part of the ballast.

So now the naval architects are going to design future boats around this jumbo alternator system that’s being proposed?

[Dockhead]

Originally Posted by Kenomac

You’re unable to purchase a generator from someplace else and have it shipped to the UK to save $15,000 USD?? I didn’t know that.

Theoretically speaking of course.... aren’t most 500-700 pound generators installed below the waterline? I know our 1000 pounder is, it’s way down low, in fact... it’s right down there with the 1700 pound battery bank as part of the ballast.

So now the naval architects are going to design future boats around this jumbo alternator system that’s being proposed?

I don't know, and it doesn't matter. You have to pay VAT and you have to pay for installation which adds at least 50% by itself. It doesn't matter -- consider it a plug number -- the point is heavy duty gensets and main engines cost about the same.


As to where the generator is installed -- Some of them are around the waterline, others are above the waterline. Mine is well above the waterline as it is mounted on a platform above the main. I've never seen one far enough below the waterline, that removing it would affect stability. Removing mine would definitely improve stability and improve sailing properties. But academic discussion as I sure as you know what, will not be doing that!


Yes, boats are being built already with large and usually double alternators, and no generators. I think we'll see more and more of them.


For Arctic cruising I would probably prefer to have some kind of separate genset, at least as backup, but I think for boats without air conditioning, and especially for boats with good solar installations, separate gensets starts to become unncessary, especially with lithium batteries.

[Kenomac]

Please splain how this new system is any different than either of my “old school” systems except that it removes one or two vital pieces of redundancy?

We have on each boat:
1. Engine with engine alternator
2. Second large (100 amp and 175 amp)alternator on the engine to charge house bank while underway
3. Generators (10kw and 13.5kw)
4. Solar 450w and 950w

Seems to me what most have is better than just tacking on a large generator to the motor, what’s so innovative about reducing redundancy?

[Colin A]

Originally Posted by Kenomac

Please splain how this new system is any different than either of my “old school” systems except that it removes one or two vital pieces of redundancy?

We have on each boat:
1. Engine with engine alternator
2. Second large (100 amp and 175 amp)alternator on the engine to charge house bank while underway
3. Generators (10kw and 13.5kw)
4. Solar 450w and 950w

Seems to me what most have is better than just tacking on a large generator to the motor, what’s so innovative about reducing redundancy?

Seems to me the real innovation is having a large output alternator with a control system that can vary it's output to allow either maximum propulsion or maximum electric production or some combination of both automatically.

[john61ct]

For me the opportunity to add tank carrying capacity would be fantastic.

[Kenomac]

Originally Posted by Colin A

Seems to me the real innovation is having a large output alternator with a control system that can vary it's output to allow either maximum propulsion or maximum electric production or some combination of both automatically.

Our boats already have this including the 2001; how is this new and innovative?
It seems regressive when you take into consideration the absence of redundancy. Lots of money for nothing new. IMO

[john61ct]

Please detail how they have this

[Kenomac]

Originally Posted by john61ct

Please detail how they have this

Please include a noun in your sentence so I can figure out what you mean. Thanks

[MaCro]

Ken, I think John was asking how your boats can vary alternator output depending on engine load.

To me this whole discussion has a couple components that are almost separate from each other. One is technology, and the other is marketing.

I've seen little to refute that the regulation/control system is indeed innovative. I think many people find that an attractive component that they'd like to have on their own boat. We can get mired down in discussions of reliability, voltage, converters, inverters, etc.

As far as marketing, it seems they've chosen to call it a "generator replacement" to help justify cost, weight, and space that a generator would otherwise take.

Regardless, perhaps this will help encourage other products that utilize smarter, more controllable regulation, especially with LFP and as newer sailors are more dependent on electronics and electrics in general.

[john61ct]

Originally Posted by Kenomac

Please include a noun in your sentence so I can figure out what you mean. Thanks

Well, the referents of the pronouns I used seemed self-evident, but here you go.

Originally Posted by Kenomac

Our boats already have this including the 2001; how is this new and innovative?

In detail, please specify, how do [they - your boats] already have [this - the below capabilities you were referring to]?

> a control system that can vary its output to allow either maximum propulsion or maximum electric production, or optimize combinations of both automatically