TerraLiner:12 m Globally Mobile Beach House/Class-A Crossover w 6x6 Hybrid Drivetrain

[biotect]

..
CONTINUED FROM PREVIOUS POST

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4. Some More Information about Capstone Corporation



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When it comes to power generation for a local application (for instance, a remote hotel), there is the added benefit that Capstone microturbines are relatively maintenance-free. Just one moving part. And with their “air bearings”, Capstone microturbines need no lubrication. So you can set up a bank of them, and let them run, and run, and run, with almost no maintenance required.

Take a good look at the Capstone website. To date, Capstone's most important market has been localized, small-scale and “distributed” power generation, for instance, off-grid power generation for isolated factories – http://en.wikipedia.org/wiki/Capstone_Turbine , http://www.capstoneturbine.com/prodsol/products/ , http://www.microturbine.com/prodsol/products/ , http://www.microturbine.com/prodsol/solutions/ , http://www.microturbine.com/prodsol/solutions/hev.asp , http://www.capstoneturbine.com/_docs/Product Catalog_ENGLISH_LR.pdf , http://www.capstoneturbine.com/_docs/datasheets/C30 Liquid Fuel_331032E_lowres.pdf , http://www.capstoneturbine.com/_docs/datasheets/C65 & C65 ICHPLiquid Fuels_331038F_lowres.pdf , http://www.capstoneturbine.com/_docs/datasheets/C200 Liquid Fuel_331049D_lowres.pdf , http://www.capstoneturbine.com/_docs/datasheets/C600 Liquid Fuel_331051D_lowres.pdf , http://www.capstoneturbine.com/_docs/datasheets/C800 Liquid Fuel_331054D_lowres.pdf , http://www.microturbine.com/_docs/CaseStudyRitzCarlton.pdf , http://www.capstoneturbine.com/company/global/ , http://www.capstoneturbine.com/company/locations.asp , and http://www.capstoneturbine.com/company/faq.asp .

And here are some videos about Capstone Corporation in general:


[video=youtube;dDF4QcwFpvo]https://www.youtube.com/watch?v=dDF4QcwFpvo&list=PL_4gcvI7N8wC_up4pejc0gGt ZjkRAmAWW [/video] [video=youtube;qCZpXjCQG3Q]https://www.youtube.com/watch?v=qCZpXjCQG3Q [/video]
[video=youtube;WmBNtoXFX5o]https://www.youtube.com/watch?v=WmBNtoXFX5o [/video] [video=youtube;_W_ULVQ0hkY]https://www.youtube.com/watch?v=_W_ULVQ0hkY [/video]
[video=youtube;wbZPphuPv1w]https://www.youtube.com/watch?v=wbZPphuPv1w [/video] [video=youtube;P3xDZLO34xk]https://www.youtube.com/watch?v=P3xDZLO34xk [/video]
[video=youtube;hgwVLvW8PTE]https://www.youtube.com/watch?v=hgwVLvW8PTE [/video] [video=youtube;GXrsg8Dn41A]https://www.youtube.com/watch?v=GXrsg8Dn41A [/video]
[video=youtube;J-DE1UCKD_U]https://www.youtube.com/watch?v=J-DE1UCKD_U&list=PLhuA58w83Z-GEGy9o8F7M0wh89ixfoMMJ [/video] [video=youtube;zqNbCkFzRs8]https://www.youtube.com/watch?v=zqNbCkFzRs8 [/video]


Also see https://www.youtube.com/watch?v=7OalMpIKkDQ&list=PL_4Ijw0zlapXqd6U2Mofp-kOGFppng3hS , and for a great animated cutaway of a 200 KW Capstone generator, see https://www.youtube.com/watch?v=koXgr2Q1zyM . For a huge playlist of Capstone vidoes, see https://www.youtube.com/playlist?list=PL_4gcvI7N8wC_up4pejc0gGtZjkRAmAWW .

As of this writing, Capstone has shipped more than 6500 microturbines worldwide, mainly “for powering offices, hospitals, hybrid electric buses and for any other industrial use. The 220-people company got a $48 million revenue last year, so their business model is profitable enough to sustain them” – http://www.greenoptimistic.com/2009/12/04/cmt-380-hybrid-car-capstone-microturbine/#.U-yfd3mSf6k .

And in the stationary, non-mobile markets for microturbines, Capstone is the undisputed world leader:

Capstone Turbine is the world's leading producer of clean-and-green, highly efficient and reliable microturbines. Capstone's 30-kilowatt microturbines are installed in hybrid electric buses, trolleys and transit shuttles around the world.

Hybrid buses with microturbines operate in such U.S. cities as New York, Baltimore and Charlotte, and internationally in London, Tokyo, Paris, Rome and Auckland. The microturbines reduce bus greenhouse-gas emissions and extend the range of these state-of-the-art hybrid-electrical vehicles.

"The vehicle market is not a new market for Capstone," Jamison said. "In fact hybrid-electric vehicle applications always have been part of Capstone's vision since the company was founded in 1988."

He continued, "The first microturbines Capstone designed and built were integrated into automotive applications. But like all new technologies, timing is everything and our initial hybrid design for cars was ahead of its time, so the company turned to the more mature stationary power markets. Now, more than two decades later, hybrid-electric vehicles are gaining interest in the market and people are taking another look at microturbines as electric-vehicle battery chargers and for public charging stations.”

….

“Earlier this year, a C30 liquid-fueled microturbine was successfully integrated into a Ford S-Max people carrier in the United Kingdom by Langford Performance Engineering Ltd. You can see more information about the Langford Whisper hybrid electric microturbine vehicle at http://www.capstoneturbine.com/news/story.asp?id=512.

The Capstone CMT-380 is a fun hybrid car with tremendous performance. Although it is not in Capstone's business plan to start manufacturing complete cars, the limited production CMT-380 and Langford Whisper hybrid demonstration vehicle are intended to showcase the technology and demonstrate value proposition of microturbines as electric vehicle range extenders," added Jamison. "Both Capstone and Langford have been in discussions with automotive industry companies, and these concept and demonstration vehicles help showcase the technology and generate public awareness of the benefits of microturbine technology."

See http://green.autoblog.com/2009/12/0...plug-in-diesel-hybrid-supercar-uses-microtur/ and http://www.capstoneturbine.com/news/story.asp?id=536 .

In short, Capstone is no fly-by-night experimental start-up company, and it probably won't disappear tomorrow. Put another way, Capstone's microturbines are not exotic, experimental technology. If you check out some of the videos above, you will soon realize that the applications of Capstone's generators are so wide and varied, that there seems little danger of the company going under, even if microturbines do not catch on as a major automotive technology.

Sure, microturbines are a potentially “disruptive” technology in multiple industries, especially (and mostly so far) in power-generation. But even here, the technology is not exactly new either – see http://www.retailenergy.com/articles/microturbines.htm and http://www.powerhouseengineering.com/showcontent.php?nav=gt&location=learning/&pointer=d4ggtmicro .


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5. The Possible Advantages of Microturbines


So to repeat my list of possible advantages of microturbines (perhaps this time you might be willing to read the full list??):

1. microturbines could be multi-fuel
2. they would be comparatively maintenance-free
3. they would be smaller and lighter than an ICE generator of comparable power
4. they would be low-emissions, or very "green"
5. for service and maintenance, they could be pulled out of the front of the vehicle on a tray, just like a more standard sort of electric generator

Again, the last consideration makes possible a flat-floor cab, and eliminates any need for the cab to tilt forward. Thereby making possible a fully integrated design, fully compatible with 360 degree access to the engine for maintenance.

To this list, I should now also add:

6. used in a serial hybrid solution, microturbines might make it easier to achieve optimal weight-balance in an expedition motorhome
7. they might provide greater design freedom



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6. This Thread is about Fully Integrated Expedition Vehicle Design


Now "fully integrated motorhome design" has been a top priority for me from the very beginning of this thread. Just read the first page. Or just read the title of this thread: “fully integrated” is clearly stated, in black and white.

So perhaps fully integrated design is not a top priority for you, Aspire. That's fine: it does not have to be.

But if so, then you are participating in the wrong thread. Fully integrated motorhome design has been a top priority in this thread right from the beginning, and it will continue to be a top priority in this thread. No matter what you write against it, and no matter to what extent you, personally, think it is trivial or unimportant, from your more “practical” or “engineering” perspective. In this thread, fully integrated design is important.

Now if you want to discuss the merits of a more traditional approach, in which cab and camper are separate; in which the cab is COE, and it tilts forwards; and the camper mounts on a pivoting 3-point pivoting sub-frame, then you should read and contribute to the “Pivoting Frames and Mounting Campers” thread instead – see http://www.expeditionportal.com/forum/threads/25494-pivoting-frames-and-mounting-campers . That's the proper place for discussion of more “traditional” and “practical” chassis/camper solutions. But not this thread.

Furthermore, it's probably important to realize that just because this thread has no interest in discussing more traditional approaches, does not mean that participants in this thread are unaware of those possibilities. The participants in this thread have tended to be just as smart as you, Aspire, and they know all about the merits of more traditional chassis designs that have engine tunnels. So again, if you want to discuss the merits of a more traditional approach at length, you are simply participating in the wrong thread.

This is a design thread, and it is a thread interested in possible design innovations, especially those made possible by engineering innovations, like microturbine serial hybrid technology. If that's not your cup of tea, then you are simply participating in the wrong thread. You seem to be getting angry at the whole thread, at the very idea of such a thread, and not at anything that anyone here happens to say. So before posting further, you may want to examine your anger, and you may want to ask yourself whether you want to continue posting in a thread whose central concern -- fully integrated motorhome design -- you hold in such contempt.


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6. Blue-Sky Automotive Design


In closing, why do care so much whether my concept vehicle is too “Sci Fi”, or not?

Have you ever been to a degree show at an Art College that teaches product and transportation design??? Have you ever seen the kinds of work that some students produce? Much of it is totally “out there”, to use Haf-E's colloquial expression. Much of it is completely unrealistic, completely unbuildable. And yet at the end of the day car companies who hire transportation design graduates do not seem to care, because they figure that engineering is the job of automotive engineers, not the designers. Put another way, the job of an automotive designer when imagining concept vehicles is to be slightly unrealistic. Slightly impractical. The automotive designer is paid to dream, paid to have his or her feet not firmly on the ground. Because only when automotive designers dream, do some truly new and unusual ideas begin to see the light of day.

For more on precisely this topic, please see post #133, at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page14 . You should read that post in full. Everything that it contains could have been addressed to you as well.

And while you're at it, you might also want to read post #94, which addresses the question, "What is Practical?", at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page10 .

Now as you said yourself, most transportation designers would never think of participating in a web-forum like this, because they really do not care whether their ideas are practical or not. I am a bit different in this regard, because I am committed to the idea that only when engineers, designers, and end-users really talk with each other, do truly wonderful new designs begin to emerge.

But "blue-sky automotive design" is not practical, feasible-right-now engineering. It never has been, and it never will be.

All best wishes,



Biotect

 

[Aspire]

No, I did not quote you. You do so long posts, and when people respond to you, you tend to ignore most of their posts anyway.

I was commenting on your tendency to get tech horny when you hear about systems/tech used in other forms of transport - hell, or even as back power systems - to the point where most of your examples are systems' tech used in much bigger vehicles/vessels. The turbine is a great point, you hear about these microturbines from a particular manufacturer, and to make your case that such thing is a viable alternative, you immediately point to super yachts, huge ships, and when challenged, points to Gunboats - a super fast catamaran that has a huge internal volume. At no point do you stop and think about fuel consumption of said microturbine, nor do you even consider if it can even run continuously run on diesel, or if it needs jetfuel/kerosene to run. My limited research of their particular turbine even shows it runs on air bearings which won't do well with bumps, such as in a global expedition vehicle.


Instead of properly addressing that, you begin your post by crying foul, and I have to ask you, if by your posts of systems in ships and super yachts you don't mean for anyone to think that those sorts of systems could somehow be viable in an expedition vehicle, I wonder why even post them to begin with? If you already know they are not applicable, why even use them as examples of alternative solutions.

I don't know whether or not a cab over is a preference, or even if a flat floor in the cab is my preference, because as I see it, I won't be living in the cab, I will be living in the back, and regardless of cab design, there will be two doors to access the cab from the ground, one of which will be used by the driver. I can see the merits of a flat floor on trucks where the driver sleeps and lives there, because he tranports stuff over long distances, and therefore prefers a cab that is better for this sort of job. It is all about application. You can do fully integrated with a conventional drive train, and to do fully integrated, that does not mean that it is necessary to do your alternative drive train, as fully integrated already exists with conventional drivetrains and you can already get cabs with flat floors. You see, the moment you're challenged evena bit, you immediately cry foul, this time, trying to push people to not respond. It must be tough for you that some people try to apply your pies in the sky to reality to check if they would work.

I can see how you're not using this forum as a back and forth between thread participants, but rather as clipboard where you clip "things that would be oh-so-cool if there were no problems implementing any of them". The moment problems with your oh-so-cool suggestions are pointed out, you immediately cry foul, while ignoring the very essense of those posts.

Do a microturbine if you wish - you also have to show it will actual work and be a practical approach that compares beneficially to a traditional diesel. To do this, you have to actually show how that can be - not only by calculations, but also how your solution is at least as good as the conventional approach. Otherwise, it's nothing but tech horniness: Oh, look, shiny thing!

 

[biotect]

Hi Aspire,

You call it "tech horniness", I call it automotive dreaming. Everyone has their role to play, and different threads have their role to play.

My role is different than yours, and this thread has a very particular function. If you don't like it, simply stop participating.

Look, if you were willing to post some concrete, tangible counter-arguments backed up by links and evidence, I would respect your feedback. For instance, if you had investigated the actual stats on ICE range-extenders, and posted them here with links, then that would have been helpful. But you don't seem to want to do the necessary work, and this kind of knowledge is clearly not at your fingertips.

You seem to imagine yourself as having pointed out genuine problems with microturbines. But it's simply not true. You have not. So far, I have seen no real arguments.

1. You have not proven that microturbines could not be multi-fuel
2. You have not proven that a microturbine would be just as much of a maintenance hassle as an ICE
3. You have not proven that a microturbine range-extender would be less thermally efficient, or less fuel-efficient, than an ICE ranger-extender of comparable power
4. You have not proven that a microturbine serial hybrid solution would not be very environmentally friendly, i.e. very "green"

You have not proven any of these things. No links, no evidence. Instead, just lots of rhetoric and hot air.

The only things that you have said, are that:


1. You think personally that all microturbines are noisy, and no microturbines can be made quiet enough for vehicular applications, by sound baffling. Except, maybe, on a boat.

2. You have made it very clear that you don't give a crap about the "design freedom" that hybrid technology opens up, and the fully integrated motorhome design that this might make possible.


So again, if that's all you have to contribute -- that you don't give a crap about fully integrated motorhome design -- then gosh, why participate in this thread at all?

All best wishes,



Biotect

 

[Aspire]

So to repeat my list of possible advantages of microturbines (perhaps this time you might be willing to read the full list??):

Aren't you just the sweetest thing.

1. microturbines could be multi-fuel

Not as easy as it sounds. Are you now also going to have those things custom made? Because as I already mentioned, even if a conventional turbine can run on diesels, they are usually limited to a very few numbers of hours of that in between rebuilts. And the microturbine you use as your example is most likely not running on diesel as I already pointed out.

2. they would be comparatively maintenance-free

I also pointed out quite quickly by linking to a thread of people knowing about that particular engine, that it runs on air bearings, and that because to get even comparable to efficiency of a normal diesel engine, those tolerances will have to be tight. THat is fine, until you take such a thing off-road or even on bad roads for months on end.

3. they would be smaller and lighter than an ICE generator of comparable power

Both are ICE engine ;-) One is a reciprocating, the other is a turbine.
Anyway, the difference being, that a diesel engine scales well when it has to deliver varying output. You don't run your diesel flat out constantly. To get that good efficiency as they claim, they are using the heat exchanger, and even so, it is merely on par with a diesel. Add to that, that if you want to keep that percentage of efficiency between output and fuel consumption, you quickly run into problems when the max power is not needed. Did you ever stop to think why it is that their pr department are only talking about efficiency when it is at full power? That thing will burn through fuel like there is no tomorrow, and if you throttle it down, the efficiency goes away.

4. they would be low-emissions, or very "green"

Not at start up, and not at shutdown, and certainly not when not needing it to run flat out. If it runs anything but flat out, the output per gallon of fuel will go down immensily.

5. for service and maintenance, they could be pulled out of the front of the vehicle on a tray, just like a more standard sort of electric generator

You may want to read a bit more about that, before thinking that would be a solution. Because of the tight tolerances needed to get efficiency, and the result of damage caused by jolts in a turbine, you may want to reconsider how you would repair the turbine itself on the road. If those air bearings can't keep the rotating parts from hitting the stationary, there is not much you can do about on the side of the road.

And with that, I am out. You see a shiny thing and some fluff press releases and immediately jump to that shiny product being viable in your application. And when countered, oh, you are once again personally offended.

But, anyway, as I don't believe you will understand or even read half of what I have written to explain (once again), I will leave you to do what you do best.

 

[Aspire]

As of this writing, Capstone has shipped more than 6500 microturbines worldwide, mainly “for powering offices, hospitals, hybrid electric buses and for any other industrial use. The 220-people company got a $48 million revenue last year, so their business model is profitable enough to sustain them” – http://www.greenoptimistic.com/2009/12/04/cmt-380-hybrid-car-capstone-microturbine/#.U-yfd3mSf6k .

There is a difference between proof-of-concept and actual products. That hybrid car is a whole lot different than a global expedition vehicle.

And in the stationary, non-mobile markets for microturbines, Capstone is the undisputed world leader:

Take note of the words "stationary" and "non-mobile, and it seems you have once again taken a fluff press release as gospel.

See http://green.autoblog.com/2009/12/0...plug-in-diesel-hybrid-supercar-uses-microtur/ and http://www.capstoneturbine.com/news/story.asp?id=536 .

Case in point.

In short, Capstone is no fly-by-night experimental start-up company, and it won't disappear tomorrow. And Capstone's microturbines are not exotic, experimental technology. If you check out some of the videos above, you will soon realize that the applications of Capstone's generators are so wide and varied, that there seems little danger that the company going under, even if microturbines do not catch on as a major automotive technology.

And you were the one accusing me of putting words into your mouth. I never said they might go under, nor did I say that that was a risk. Where are you pulling that from? Oh, never mind, I know.

Sure, microturbines are a potentially “disruptive” technology in multiple industries, especially (and mostly so far) power-generation. But even here, the technology is not exactly new either – see http://www.retailenergy.com/articles/microturbines.htm , http://www.powerhouseengineering.com/showcontent.php?nav=gt&location=learning/&pointer=d4ggtmicro.

Turbines are nothing new. But we are not talking about using turbines in a stationary environment, nor about using it on a hybrid bus. We are talking about using it on a global expedition vehicle which see its shares of bad roads, and something that should last for years and years in such an environment.

I take note that you just regurgitate your list, without considering any point I made whatsoever, which brings me to this:

In closing, why do seem to care so much whether my concept vehicle is too “Sci Fi”, or not?

Erm, because a project where you think you can just use any tech, no matter if it is possible, it is a meaningless exercise. With the notion that it doesn't have to practical, applicable, or even remotely feasible, I might as well "design" a global expedition vehicle with 6 axles, weighing in at 1 ton, propelled by individual electrical motors on each wheel, and run by batteries that only weigh 30kg all-up, charged by two solar panels on the top. Oh, and while we are it, it should be retrable both in width and length and height when needed, so it doesn't take up more room than a family car, but be capable of extending to 20 meters to maximise living spaces. Water, schmater, we will bring powdered water.

See the problem, when you think things doesn't have to applicable to physics and practical and technological limitations.

I promised I would leave you to it, but when I posted before, you had posted in the meantime, but this time I am out. What a waste of time, debating solutions for a specific thing, when that person can't see why one should see if the tech is available, or even why one should check if solutions found would actually work. :smilies27

 

[Aspire]

Oh, look, you edited your post to make it seem like you said something differently after I responded to that post. I guess I should have quoted your post in its entirety, but I didn't realise you would be that dishonest. You even removed all that idiotic stuff about doing an exercise where it didn't matter if was practical at all. FFS.

Edit:
Your almost complete revision of that post makes sense in the light that you don't want to adhere to reality and practical application of said technology.

The (new) turbine argument that I have not shown it can't be multifuel is a good case in point: Capstone themselves - the product you used in your example - call them "liquid" fuelled turbines, and if you knew about turbines as used by aircraft, you would know that although they can run on diesel, they can't do that solely or for very long. You try to change the burden of proof, and attempt to have it be my burden to prove that a turbine cannot be truly mulitifuel, but the burdon on proof if on you. You are the one taking a sales pitch from a company on a specific product, and simply assume it will run on diesel with no problems, even if the company themselves call it "liquid" fueled, and not "diesel" fuelled.

Seriously, at this point, the dishonesty exhibited by you is what p's me off the most.

 

[optimusprime]

Glad to hear it. Yes, there was a great deal of information in that sequence, from post #491 onwards. My apologies for the information overload. But seemed necessary to post it all together, so that microturbines would get a fair hearing.

What really amazes me is just how little discussion there is on ExPo of hybrid technologies, given that ExPo is a "vehicle" website, where most participants seem interested in machines. Just do a google search for "Expedition + Portal + Hybrid", and very little comes up.

Whereas in the world of automotive design and engineering, professionals can't seem to talk about anything else. Indeed, I was so sick and tired of hearing about hybrid technology, that at the beginning of this thread I tried to avoid the topic. I really wanted to think about and discuss all the other aspects of large expedition vehicle design instead. Not hybrid technology.

But then dwh posted about microturbines, and a light went off in my head, and.....

All best wishes,




Biotect

I will admit that a lot of this is over my head,but all the same it is thought provoking and interesting.
I have a laymans general interest in all aspects of engineering and find some of this hard to compute,so to speak.

Anyways ......
My laymans mind can see possibilities in this idea.
To my thinking this could go a couple of ways, use an electric motor to drive the standard gearboxes axles etc, or have electric motors in the wheel hubs,thus rendering the axles and driveshafts redundant, (like a lot of heavy quarry machinery does) http://liebherr.com (look for mining trucks)
This could then free up space under the vehicle for extra fuel, batteries etc etc.

If you could duct the exhaust from the turbine somehow under the cabin floor,could you not use that as a 'heated floor' type system, obviously you'd need a way of ducting it elsewhere if you're in the middle do the Australian outback in summer?

Steve.

 

[biotect]

Hi Aspire,


Finally, a more substantial post! In which you actually try to make some arguments!

Because the issues are numbered, my responses can come in quick succession:


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1. It's your word against Capstone's. The Abrams tank is an example of a land-vehicle that has a turbine that runs on diesel all the time. The CMT-380 sports car was advertised in promotional literature, and on all automobile websites, as a diesel. Please remember that I did not post just one example of Capstone's implementation of microturbines in vehicles. I catalogued nearly a dozen from post #491 onward.

So who am I supposed to believe?

Yours is an interesting skeptical claim, one that I would like to research further. But your claim is surprising, and runs contrary to the "official" stuff that I have read in any number of other contexts. I have never come across your claim before, in any description of turbines. If you could point me to secondary literature that backs up your claim, that no turbine should run on diesel for extended periods (i.e. months), that would be great. But it seems that you simply want me to take your word for it, because (you claim) this is common knowledge with regard to aircraft turbines.

However, as far as I know, no Capstone microturbine has ever been installed in an aircraft. So it seems at least possible that a Capstone microturbine more resembles the turbine in the Abrams tank, than it does the aircraft turbines that you are familiar with. In the absence of any links to material that might settle the question (i.e. aside from simply pointing out that Capstone describes its microturbine as "liquid fueled"), you still haven't convinced me.

And no, I was not thinking of custom design.....


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2. The idea that the air-bearing in the microturbine might be incompatible with the shocks and jolts of expedition motorhome travel is a much more interesting claim. I wonder how Capstone would address this claim. The Lethantia is a sailing yacht, and although the jolts would be different, in heavy seas one would hope that her Capstone microturbine would keep running. The truck applications of Capstone microturbines so far have been for vehicles that drive on paved roads. So yes, this is a potentially interesting problem. Thanks for pointing it out so clearly.


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3. Sure, even a turbine entails "internal combustion". But we need a handy way to distinguish between an engine that has rods and pistons, and a turbine. So the convention now is to call the former an ICE. Saves the trouble of constantly having to write, "diesel engine with rods and pistons".

As I stated earlier in the thread, microturbines are fuel-guzzlers when they drive wheels directly, for precisely the reason you mention: because microturbines are only fuel efficient when they run flat out, at maximum RPM. Otherwise, microturbines are not scalable as per diesels. That's why Jay Leno's EcoJet is a fuel-guzzler. But it's also why the Capstone CMT-380 super-car is not a fuel guzzler (or is claimed to be not a fuel guzzler). Because in a serial hybrid configuration, the microturbine would only run flat-out, at maximum RPM, when it charges the batteries.


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4. As for fuel emissions, again, it's your claim against Capstone's. Or even worse, it's your claim against California and the EPA. Capstone has stated that the exhaust of its microturbine is so clean, that it gets a waiver from California and the EPA on needing any kind of after-treatment. This topic, too, was addressed earlier in the thread -- see post #502 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page51 . For a more technical description as to how the Capstone C30 microturbine achieves such low emissions, see http://www.seeei.org/EL2013/Article/015-ART-EN.pdf . The following is a quote from the same:

Capstone microturbines use a lean premix combustion system to achieve low emissions levels at a full power range. Lean premix operation requires operating at high air-fuel ratio within the primary combustion zone. The large amount of air is thoroughly mixed with fuel before combustion. This premixing of air and fuel enables clean combustion to occur at a relatively low temperature. Injectors control the air-fuel ratio and the airfuel mixture in the primary zone to ensure that the optimal temperature is achieved for the NOX minimization. The higher air-fuel ratio results in a lower flame temperature, which leads to lower NOX levels. In order to achieve low levels of CO and Hydrocarbons simultaneously with low NOX levels, the air-fuel mixture is retained in the combustion chamber for a relatively long period. This process allows for a more complete combustion of CO and Hydrocarbons.

In addition, the exhaust of microturbines can be used in direct heating or as an air pre-heater for downstream burners, once it has a high concentration of oxygen. Clean burning combustion is the key to both low emissions and highly durable recuperator designs.

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5. This is really the same issue as 2, and the jury is out.


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The post that immediately followed the point-form post was not very cogent, so does not seem worth addressing at length. I can only repeat that my presence on a web-forum such as this, indicates that I am keenly interested in the more "practical" side of expedition vehicle design. You are absolutely right when you mock transportation designers who create concepts that are completely unrealistic. Art colleges are full of such designers. It is exactly because I do not want to become such a transportation designer, that I first began blogging on ExPo.

But so too, it's important to remember that transportation design is not just engineering. Physical constraints are real enough, and yes, one has to respect the laws of physics. But people expect much more from a motorhome than that it should merely "work", at the engineering level.

People appreciate good design, where this means design that fuses aesthetic, psychological, and social considerations, with more "functional" engineering considerations. It drives automotive engineers nuts to hear this, but a real "deal-breaker" for many people when buying a car, is the size, number, and location of the cup-holders. Yes the cup-holders. People now expect cars to have well-designed, well-located cup-holders. And they will decide against buying a car, no matter how great its engineering and its engine, if the cup-holders are not exactly right.


********************************************


In summary, you kind of have to expect that in the absence of supporting links, people will not take contentious factual claims seriously. Sure, new technologies are always sold with some measure of hype, and what they don't tell you is often as important as what they do tell you. But simply pointing this out, is pointing out the obvious. Simply pointing this out is not enough to refute the claims they do make in their promotional literature.

And please remember, I don't work for Capstone. At present, in fact, I don't work for anyone. I'm just an MFA student trying to figure out whether a certain technology -- Capstone microturbines -- might be at all realistic as part of a serial hybrid power train in an expedition vehicle. I am not even the one who first posted about microturbines in this thread. That honor goes to dwh.

As for the "burden of proof", if you are not willing to provide links that people can follow through on their own, so that they can make up their own minds, then you will always fail to convince people on a web forum regarding contentious factual claims. Simply appealing to one's personal authority on a blog like this just doesn't cut it. I haven't met you, Aspire, I don't know who you are, or what your expertise might be. But even if I had met you, and even if turns out that you have a PhD in mechanical engineering, when contentious factual claims are in dispute, people are expected to footnote. Even those who have PhDs in subjects in which they are considered expert, must footnote their claims.

You seem disinclined to do this. We are just supposed to believe you, well, because you are you.

All best wishes,



Biotect

 

[dwh]

.

In short, I was asking something dwh different. The exhaust contains all the heat energy that remains left over after the microturbine has powered an electric generator. In the example of the "Argonon" ship discussed above, that very hot exhaust is then put through a heat exchanger to heat water, which in turn heats the crew accommodation -- see post #523 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page53 . So I was asking dwh how he thinks a similar arrangement might work in an expedition motorhome, with a big camper in back.

dwh: any thoughts?

Actually, I took the heat->water->cabin/<other uses> as a given. That's how it's done in most ExPo trucks. Generally a diesel fired "hydronic" heater such as the U500's Thermo 90, which is used to provide cab heat and also used as a pre-heater for the main diesel engine; when a camper is added, they tap that "cooling system" so that the hot water thermal mass in the camper is heated by either the main engine (when running) or the hydronic.

Heat is needed for more than just the cabin; water tanks (if ambient =< freezing point of water) need to be heated if they aren't inside the cabin. I can see where you might as well also use it to keep the fuel and/or battery (and water maker ) at a decent working temperature.

Could also be plumbed for on-demand heating of the solar array, to melt snow and ice and such. (In fact, an old idea for charge controllers (and I could swear I once saw one that did it, but have never found it on the net again) is to backfeed power from the battery into the PV modules to use the solar cell P/N junctions as heating elements to clear the PV modules. I believe MidNite toyed with the idea as well when they were developing their "Classic" charge controller.

As for how to do it, I would expect that simply running the exhaust through a heat exchanger would be enough:

http://www.eberspacher.com/products/fuel-operated-heaters/water-heating/technology-in-detail.html


Here's the heat exchanger section from a Thermo 90:

Just route the microtubine exhaust through one of those and call it a day and have a beer.




Keep in mind also, that engine coolant temperature, or exhaust temperature is way too hot for most uses. So don't forget to incorporate thermostatic mixing valves where appropriate:

http://www.watts.com/pages/learnAbout/temperingValves.asp?catId=

 

[biotect]

I will admit that a lot of this is over my head,but all the same it is thought provoking and interesting.
I have a laymans general interest in all aspects of engineering and find some of this hard to compute,so to speak.

Anyways ......

My laymans mind can see possibilities in this idea.

To my thinking this could go a couple of ways, use an electric motor to drive the standard gearboxes axles etc, or have electric motors in the wheel hubs, thus rendering the axles and driveshafts redundant (like a lot of heavy quarry machinery does) http://liebherr.com (look for mining trucks).

This could then free up space under the vehicle for extra fuel, batteries etc etc.

If you could duct the exhaust from the turbine somehow under the cabin floor,could you not use that as a 'heated floor' type system, obviously you'd need a way of ducting it elsewhere if you're in the middle do the Australian outback in summer?

Steve.

Hi Steve,

Yeah, I think this stuff is pretty exciting, too. I never get tired of it, and I don't really know why.

I was always drawing vehicles -- any kind of vehicle -- when I was a boy. Mind you, I never played with "Hot Wheel" cars or anything like that. Instead, my father was one of the first to try to import "Fischer-Technik" into North America, so I had literally mountains of the stuff. Fischer-Technik, just in case you're not familiar with it, is a Mecanno-like construction system that has been popular in Germany for decades -- see http://en.wikipedia.org/wiki/Fischertechnik , http://www.fischertechnik.de/en/Home.aspx , http://www.fischertechnik.de/en/Home/info/history.aspx , and http://www.meccano.com/uk/ . Fischer-Technik begins at a very basic level, and it gets so complicated, so electrical, and so servo-controlled, that engineering students specialized in the design of manufacturing plants will use it to "trial balloon" ideas -- http://www.fischertechnik.de/en/Home/products/junior.aspx , http://www.fischertechnik.de/en/Home/products/industry.aspx , http://www.fischertechnik.de/en/Home/didactic/competitions.aspx , http://www.fischertechnik.de/en/Home/didactic/links.aspx , http://www.fischertechnik.de/en/Home/downloads/computing.aspx , and http://www.fischertechnik.de/en/Home/downloads/product-videos.aspx . So I first built vehicles with the stuff, and when I was 11 years old, I built a robot of sorts.

Last time I checked, Fischer-Technik was widely distributed at retail stores throughout Europe, but distribution in the the United States was limited -- see http://www.fischertechnik.de/en/Home/info/dealer-search.aspx . But I haven't been back to North America for a few years, neither Canada nor the United States. So perhaps things have changed? Some German economists will claim that the ultimate explanation of Germany's continuing manufacturing and engineering success is Fischer-Technik, because Germans kids literally grow up on the stuff. In my own case, however, I was good at drawing, and I loved Art. So a more "design" path seemed appropriate, instead of engineering.

Now in relation to your post:

1. At one point in the thread, and I can't remember where, egn seemed to suggest that electric motors might be incorporated into the Tatra backbone tube. I wonder what egn meant by that?

2. As for venting the microturbine exhaust to heat the camper, yes, there would have to be an alternative; a way to shut it off.

But before going down that road too far, Aspire's skepticism regarding microturbines does seem worth investigating a bit further, even if the way in which he made his points seemed a bit obtuse. So it might be good to send an email to Richard Hilleman, for instance, asking whether the Capstone C 30 microturbine in his CMT-380 sports car really does run on diesel, all the time, without problems. And if indeed any Capstone C 30 can be designed to do that. Second, it might be good to send an email to Capstone itself, inquiring whether their air-bearings could withstand the jolts and shocks of expedition travel.

Beyond that, I am now really curious about the comparative thermal efficiency of a Capstone C30 microturbine, without CHP, relative to the best current ICE range-extenders. Perhaps Haf-E or dwh might know?

All best wishes,



Laurence

 

[biotect]

.

I can see where you might as well also use it to keep the fuel and/or battery (and water maker ) at a decent working temperature.....

Hi dwh,

I wondered where you were!

Yes, let's not discuss water makers, at least not for a few more pages.....:hehe:

Let's first give microturbines some time to settle in.....

No doubt you've read the previous correspondence. What do you think about Aspire's skepticism? For instance, does he seem right in thinking that a micoturbine could not be run on diesel continuously? And/or that it could not be multi-fuel? And what about those air-bearings: could they withstand the shocks of expedition travel? And what about thermal efficiency? Even if the microturbine were only driving an electric generator at maximum RPM and efficiency, and only when charging the batteries, do ICE range-extenders exist that are more thermally efficient?

And so on.

All best wishes,



Biotect

 

[optimusprime]

Air bearings ... Something is scratching the back of my mind,but I don't know why.
If the bearing housing is sealed, and the air was at Sufficient pressure, would that not hold it centrally,and keep it from hitting the outer casing?
As I say, this reminds me of something but I can't recall where or why.........

 

[dwh]

To address the flame war...


I thought pie-in-the-sky was the name of the game.
The OP clearly stated that the purpose of this was to brainstorm ideas for a THESIS.
He didn't say he was going to actually BUILD the bloody thing and try to mass-market it.

A thesis about building an INTEGRATED vehicle, rather than independent cab/cabin.
Integrated so as to maximize LIVING SPACE.
To use the cab as PART OF the cabin, when not using it as a cockpit.

So WHY rag on him for tossing out goofball ideas?
And besides - it's HIS freakin' thread.
When he overposted on someone else's thread, he went back and cleaned up his mess and got it out of THEIR thread.

Well okay, if it's all about the brainstorming...
Hell my brain is a walking talking storm; it's cross-wired (some would say mis-wired) 6 different ways from Sunday.
Thinking outside the box?
I ignore boxes.
Until I bang my head on them.
But I'm 6'4" tall - I'm used to banging my head.
And I'm a head-banger from way back anyway.



So I tossed out the FAR OUT SCI-FI idea of using a HYDROGEN FUELED micro-turbine.
Diesel?
We don't need no steeenkin' diesel!
Screw diesel.
Screw hydrocarbons.
Screw the Oil Industry.
Screw G.H.W. Bush and his globalistic feudalistic fascist cahootin' crony monopolists who lie and call themselves capitalists.

And I never said Capstone either.
Way too big for what I had in mind.
30kw?
Geez...I was thinking more like 3kw.
Maybe 5kw.
Someone asked, "Are you going to have your turbine custom made?"
Well...of course.
It's not hard.
I said Bladon because they're cool.
But if it was me doing it...
This.




Practical?
Who said anything about PRACTICAL?
I presented it as a one-off special construction vehicle to grab a few spots in the Guiness Book.
I mean, let's get real for a second...that Man Kat 8x8 with the 1100hp Leopard Tank Engine isn't PRACTICAL.
No one cares though - it's a RACING vehicle.
Doesn't HAVE to be practical.
It just has to work.
More or less.
Most of the time.
As long as someone tinkers with it.
Tinkering is fun.


And yea, biotect is definitely an information junkie:

But so am I.
My opinion is...
Anyone who can't keep up...
Screw them too.
Not my fault or my problem.
Blame their parents (I do).

 

[biotect]

Hi dwh,

Thank you.

All best wishes,



Biotect

 

[biotect]

...

The capstone microturbine is a generator - it gives all of its output as electricity. So no need to add another generator.

Using the exhaust for heating would be pretty straightforward - just duct it to the outside sitting area! JK - but a heat exchanger to efficiently drop the high temp exhaust to interior heat is bulky - might not have enough space available. The equipment required to use the waste heat for cooling would be way to large to fit into a expo-bus type rig - better to use conventional air conditioning / heat pump equipment.

Kerosene is widely available around the world but often is at a higher cost than diesel - so no real savings there.

I would say the possibility of this working out for a expo-bus type rig is pretty far out there - maybe for something like the MaxiMog/KiraVan guy who doesn't seem to go anywhere in his rigs - but it could be interesting to do the same thing with a more conventional diesel generator system. Expo rigs have the advantage of usually only being driven for limited periods of time each day - so a smaller generator running for longer periods of time to recharge a large battery bank might be a viable option. Coupled with a smaller vehicle for local explorations (motorcycle etc) it might work. When power is available (i.e. RV park) then the generator wouldn't need to be operated. A conventional generator would be easier to have repaired and is already designed for severe vibration etc.

The military has been working on this for a long time - here is a short summary of projects done in the 1993 which consisted of a HMMWV with a 1.9L VW Diesel engine powering a generator and then either two motors (one per axle) or four motors (one per wheel). At the time the performance of the batteries doomed the project - but now with viable Li-Ion storage I think it is practical - just expensive.

http://www.alu.army.mil/alog/issues/MarApr01/MS635.htm

Hi Haf-E,

Good to hear from you. I don't know if you've been following the last few pages. But if you have, what do you think?

In particular, I was wondering what you think the comparative thermal efficiency might be of a C30 Microturbine versus and ICE range extender. Are you familiar with recent range extender developments? Because a range extender can be somewhat smaller and more compact than an engine that directly drives the wheels, I've read that some of the range extenders now appearing on the market are very fuel efficient. But just thought I'd suss you out on this, before I post some possibilities.

Also, what do you think of Aspire's argument about the unsuitability of the Capstone microturbine's air-bearing for expedition travel?

All best wishes,



Biotect