Micro CoGen.

Withdrawal symptoms all around!

At least I have some time left over to come here and refresh my participation a bit on alternative technologies. I am glad to see the additional topic areas starting up here as well!

dieselgman

+1 to all said about thermal isolation between inner and outer walls plus AirHandler to provide adequate ventilation for a healthy inside environment. I have long worked in the building trades in Alaska... including a lot of work in remodel insulation renovations for arctic environments. The overall physics of heat transfer apply equally to retaining heat vs rejecting heat. Double walls are common enough for super-insulation.

There are also other options that can work out as well and be much lighter for use in micro-housing. We have used structural foam panels - up to 9" thick. These are sometimes plywood structural frames and sometimes 18ga steel frames cast within the foam sandwich. What you get is both an extremely solid structural performance combined with the superior thermal performance of closed-cell foam in a lightweight panel, basically prefabbed walls you can put together like building blocks of any given size. Since the foam is heat expanded into the voids, the panels become ultra-solid and thermal performance is also exceptional.

We often used a manually controlled 4" (thru-wall) Scandinavian vent device for each occupied room, especially for kitchen and bath, to help control moisture buildup. Low-tech and very effective. The problem with super-tight housing is often condensation... properly controlled ventilation and a proper super-tight vapor/air barrier (inside for winter, outside for summer) is a big part of maintaining a healthy environment. Condensation is your enemy as it gives rise to mold growth and other unhealthy and destructive conditions.

dieselgman

I would have an interest in such an initiative... reinstate at least a few of the hobby exemptions for small-scale practical applications.

At the very least I can lend a few decades of practical experience... perspective.

dieselgman

We love doing business with Tom at CGG. He is just a fine personable gentleman and seems to run a fairly tidy business. Our time and energy for importing has always focused on the Lister parts in the past and China has been a bit difficult to get started with. I think some of the language and cultural barriers are an issue at times in dealing with Chinese manufacturers. Even basic technical language seems to fail in translation to Chinese. We shall see shortly if they can follow instructions and deliver on all promises. I know they are technically capable engineers in their own right and that most of the big brands are now manufactured there - Marathon is among the crowd to have shifted their manufacturing operations out of the USA to the Chinese mainland.

dieselgman

Back on line now...   

dieselgman

I do not have exact precise information even about the Marathons... but they tend to have extra heavy windings and core plates. I would not expect all the weight increase to reside in the rotor alone for any model as they usually increment both rotor and stator capacity together.

I operate Diesel Electric by the way (both Alaska and Kansas)... and our next container out of China will have the full range of ST product as well as other brushless generator types. We also do business with Tom at CGG and normally stock his product in our Kansas warehouse for inclusion with our engine kits. Our pricing is actually a bit under Tom's on an apples to apples comparison. Our ST heads are specified with all copper windings, all aluminum fans, all highest-quality name-brand bearings, all highest quality AVR controls. This costs quite a bit more initially but is worth it in the long run in problems avoided.

dieselgman

We know the Marathon heads pretty well... and each 2 1/2kW increment of increased rating equals about 3/4 inch of extra winding length and mass on the rotor. (maybe about 15 to 20 lbs). Who knows what the Chinese are doing with the ST models???

dieselgman

I took a look at some of it today at our local library... it is easily several thousand (maybe up to 10,000) drawings per reel. (I did not get one third of the way to the end of one reel in a couple hours at a steady clip.) As a parts engineering archive, it appears to have everything needed to reproduce any portion of the "current" engines (in the early 1960s). Very detailed and precise drawings and specifications for each part. Unfortunately, the collection seems to rely on an indexing system that I have no resources for deciphering... maybe lost to history now.

Typical reel markings as follows: Reel # 2 "A" Size Current Drawings    START: 47314545    END: 47390101,   "B" Size START: 10007   END: 11291

I am researching the costs of digital conversion including maybe finding a good scanner to use.

dieselgman

I have in my possession a significant volume (26 very long reels) of original microfilmed documents from Witte Engine Corp. - Kansas City. All microfilm dated January 3, 1968.
Included are 13 long 35mm reels of engineering drawings, service drawings, A B C and D current drawings.
Also included 10 long reels on 16mm covering parts, bills of materials, specifications, group numbers, engine models etc..
This appears to be some very significant coverage of the Witte technical history as it existed prior to January 1968.

I am aware that this material can be converted to digital or printed directly from the microfilm reels.

Any interested parties or suggestions?

dieselgman

We do not see much difference between the compressor or the kit approach to getting past US Customs. The kits currently available are perhaps slightly more work to finish, but they are actually assembled up to the top of block and can also be finished in an afternoon. Some of our clients have approached them this way with good results. Others have preferred a full "build-from-scratch" approach. Plenty of options available!

Best of luck!

dieselgman

We lost the roof on our parts/apartment building on April 15... so I can no longer say I haven't been hit. Big mess, but no one hurt.

dieselgman

We have some Shibaura gensets in our Alaska stocks - with starters attached. At least one is lacking a water pump so I wouldn't mind parting that unit out. It will be at least a month or two before I can get back to that shop though...

dieselgman

First idea that comes to mind... Why? There would be far too much wasted energy in this scenario. Of course the electricity could be run through additional heating elements in the boiler jacket to improve efficiency and loading so that would not be "waste".
If you have natural gas available... then a direct boiler offers the most efficient transfer of energy that I am aware of.
Many engines can be converted to run NG but cost would be the next problem... by the time you added an ignition system, you would certainly blow out a $2,000 budget - even if using a low to no-cost basic engine. The Germans (and other Europeans) have fine tuned a number of micro-chp units for mass consumption, but alas - not in the low-end price range either.  

dieselgman

I have built underground concrete storm shelters at both my Kansas locations... I've never been hit directly by one of those tornadoes but central Kansas is certainly known for them. I wouldn't want to be without a good place to duck!

dieselgman

We are often in the crosshairs in central Kansas... a small twister did some damage about 25 miles away this time. That wild weather can sure be a problem for life and property.

dieselgman