Micro CoGen.

http://gullis.org/baat/Baatsider/motor_historie.htm

Some history shows they built their own horizontal back in the 30's however there were german models very similar around that time, so maybe they were influenced.

You might check with a walgreens or elsewhere that has a competent photo department, possibly a camera shop.  They may offer conversion services.

I've seen it done using about a $1200-$2000 film scanner at a library before, but that is about it.

Here is some information on process options.
http://www.andromeda.com/people/ddyer/photo/slide-transfer.html

Another thought occurs.  The DC version of the Honda EU gensets the AlphaGen models produce 48-52VDC output.  This is ok for maintaining and somewhat charging a bank, but won't equalize it.  They have an AVR on them just like the AC model, why couldn't someone replace the AVR with something that can get the voltage up to 60vdc or so?  Has anyone replace the AVR's on the AC model?

http://www.ebay.com/itm/ALPHAGEN-DCX3000-36-48V-DC-GENERATOR-NEW-WITH-ACCESSORIES-041-028-10-/321772512458?hash=item4aeb22e4ca

Not too much that is great information, I guess I didn't understand MPPT all that well (or any of this really).  I suppose with some clever wiring to split the bank on the golf carts for charging in halves could work, only fear there would be have imbalanced bank maybe.  Don't currently have a method besides full oversized AC generator running full blast to power the AC/DC golf cart charger, this works but obviously isn't efficient at all and not as portable.  Was just trying to come up with a smaller more portable method to charge 48v banks directly regardless of location (woods, pasture, wilderness).  Will have to research further.

A thought occurs since you mention breaking the banks down for charging.  I wonder if I couldn't use a battery isolator like for RV use to charge the bank in 24v segments.

https://www.emarineinc.com/categories/Battery-Isolators

Looking to make an off grid 48v bank charger for mobile applications (utility/golf cart type banks) when coupling a 555-JHO to a small engine like a gx series honda, It has been advised to use one of the marine voltage regulators for soft start and ramping up.  Question is, in this setup do also need to use an MPPT charge controller?

Great information, thank you.

Maybe trying to source a couple packs from hybrids at junkyard?

http://imgur.com/a/wRdFA

Pictures of the beast.

What will you do for fixed speed governing?

After some more research seems it would be more economical to build an exhaust heat exchanger to run more common/cheaper engines in horizontal shaft.

I've had a similar theory based on some of the newer switching locomtive units which make use of 3 small (say 8.3L cummins or the likes) engine/gen units where the primary unit (which can be any of the 3, round robin even) would run all the time during a duty cycle, the second engine/set would start as load demands and shuts down if load falls blow threshold for a moderate period of time.  The third unit kicks in as load requires, but is also more aggressivley disabled as the load lowers.  The idea being that most of the time only 1 engine is running, some of the time 2 and only occasionally all 3.  Built moldularly, the units should be interchanagble, where any of the group can serve any role and be swapped out or disabled in the controller as needed for maintenenace.

https://www.youtube.com/watch?v=PqwHB6jX7vM
http://www.northeastdiesel.org/pdf/low-emissions-switcher-012206.pdf

So in a CHP system we might design a basic system that eploys multiple units of gensets, maybe even identical or mix match.  Say you have 3 vanguard natural gas converted engines coupled to 2.5kw or so output alternator, feeding into a bank.  A controller could monitor the status and track the hours/usage of the modules to keep them even or mark one as disabled for service or the likes.  Monitoring the battery bank, you can start 1 unit as needed, if the draw keeps increasing add a second or all three.  The inverter portion is getting the power out of the battery bank instead of directly.

This would have a higher cost of build, though you could be using smaller engines and cheaper alternator sources.  The benefit would be in the managment of the modules maintenance windows.  While your total capacity for generation could say be 7.5kw of charging into your bank, 900 hours of generation would not be 900 hours of operation on a cheap gas engine.  It would ideally be ~300 on 3 engines.

Surplus center has some 26hp Kawasaki liquid cooled twins for under 1k right now.  Might be decent project engine for CHP?  Not sure how they are on fuel.

I'm inclined to agree that you need a small efficient "prime" unit that can do the basics.  Maybe an inverter generator for those loads, as they're quiet and can adjust idle as needed to the load demands.  A large "stand-by" is nice though, but you kinda need to plan out a schedule for loading it down properly.  Which in an outage may not be a big problem if your neighbors are within drop cord range.

Don't think I can swing it right now with buying another engine already.

I found this one on craigslist not all that far from me, but if someone is in the midwest it might be a decent deal.

http://stlouis.craigslist.org/pts/5086551129.html

Now see there are two camps on their fuel consumption.  Some argue they are one of the best on fuel if in tune.  We've had a few before in trucks and industrial equipment and they seemed to be rather fuel friendly, especially compared to their cat neighbor.  I think most of the genset units were rated at 1200rpm, which is low for a 53 series detroit I would think.