Micro CoGen.

You're inspiring me!  I have an R175a (crank start), and an ST-5 that I've never used.  Been thinking of what to do with the engine.  Never thought of direct coupling it, but it makes a more compact installation that way.  Good job!

Solar panels and lead/acid batteries.  Friend's friend isn't going to live there full time.  It's a retreat for him to get away to on weekends.  He owns a small manufacturing business and has no family, so it's just him and a Maine Coon cat. 

A friend helped his friend deliver his new "tiny house" to Herron Island in Puget Sound.  Somehow he located someone with a construction barge to take the house on a flatbed trailer and 4x4 pickup to the island.  Because of the 12' tidal range and the geometry of the landing site, it was important that they got there pretty close to high tide.  When they got to the island, my friend realized to his horror that he had left the keys to the truck in his car back in Tacoma.  So he was marooned with the tiny house/trailer/pickup on a construction barge on a falling tide. 

It turned out that a (ridiculously wealthy, as it turned out) Herron Island resident who was watching the landing had a really fast boat and the two of them made a relatively quick 35 mile (one way) trip to Tacoma and back.  They managed to get the tiny house/ trailer off the barge, but just barely.  Something about a big maple tree and the 4x4's winch was mentioned, but I didn't get the details. 

Quinn

Speaking of small houses and code, and such, how does the treehouse Dude get past the bureaucrats to build treehouses with all the amenities?  Seems the concept of putting a (small) house in a tree, even if it wasn't for habitation, would generate a red tag in a New York minute.

Thanks for the video.  Aren't these great gensets?  I have an ST-2 powering a 7.5 kW generator.  It's electric start, but I have to flip the decompressor levers manually.  It's for standby power at our house on an island in Puget Sound.  Trees/branches have a tendency to fall across power lines during the winter when the soil gets saturated with rainwater, hence the need for reliable backup power.  Yes, the thing is noisy.  It sounds like rush hour at a truck stop, but it is reliable and starts every time.  I'm considering pulling it out of the shed and selling it, and replacing it with one or both of my 6/1s in a proper generator shed.  But for now it sits there, waiting for the next power outage.

A research engine is an instrumented test engine whose characteristics are very well known.  Data gathered from running such an engine can be mathematically scaled to predict the performance of a specific fuel and running condition in a larger real-world engine.   That's what I think they meant by their predicting 59.5% efficiency in a truck-sized engine.  The Cat test engine generated the data.  The data was then scaled, knowing the efficiency of the test engine, to predict what would happen in a larger real-world engine.  

A 6/1 is maybe 25% efficient, in terms of BTU (fuel) in vs. KW out from an ST-type generator.  The generator is maybe 80% efficient, so figure 25/0.8 = 31% efficient, but that's probably optimistic.  It's not a particularly efficient engine because of the small displacement and large mass of iron that wicks away heat.  While combustion temperature and exhaust temperature of a 'roid are about what one would expect for a naturally aspirated compression ignition engine, that's not the whole story.  Hotater reported that his long-running 6/1 had trouble getting the crankcase oil temperature above about 115 degrees F.  That's not optimal for efficiency.  And remember that it's an 85 year old design that came into production in the latter days of the age of steam.  

A good example of an efficient engine would be any of the gasoline engines that are used in hybrid cars like the Prius.  It's compact, multicylinder, with a multivalve head with variable valve timing, huge air intake manifold cross-section, and it uses a modified Atikinson cycle, in which the compression stroke is shorter than the power stroke.  That's achieved via valve timing rather than through complicated mechanical linkages, as in a true Atkinson cycle engine.  So pumping losses are reduced compared to a standard Otto or Diesel cycle engine.  Wikipedia has a great animation which shows the concept.  The current generation Prius engines have a thermal efficiency of over 40%.  Current thermal efficiency of the largest IC engines are those used in large ships, which are over 50% efficient.  http://www.emma-maersk.com/engine/Wartsila_Sulzer_RTA96-C.htm

http://en.wikipedia.org/wiki/Atkinson_cycle

Quinn

Oh, and if you want to start an argument, just tell Bob you want to erect wind turbines in his town (ducking!).   

Quinn

Gasoline burns relatively slowly and consistently with a relatively slow flame front speed.  Same with methane, but propane burns faster and less predictably.  Sir Harry Ricardo's book, "The High Speed Internal-Combustion Engine," available for $215 from Amazon, or for 35 lbs. ($52 U.S.) from http://estore.ricardo.com/shop/the-high-speed-internal-combustion-engine/ discusses fuel and everything else you want to know in much more detail than you would have thought possible.  It's worth poring through, though it's not an easy read. 

Propane injection is touchier to implement than is natural gas (methane) injection at the high compression ratio of a diesel engine because at high pressures the fuel and oxygen molecules are much closer together than they would be at lower pressure.  Thus, the fuel/air mixture burns faster, which isn't a good thing for efficiency or for the life of the mechanical components.  However propane works fine as a fuel in spark ignition engines at low compression.  I played around with it enough to convince myself that the ugly noises coming from the cylinder probably weren't good for the engine.  Ricardo has photographs of the flame front in his book, which is worth the price just to learn how such things are done. 

Whatever you do, you're going to have a hard time getting that kind of thermal efficiency out of something like a 'roid than you will out of a larger engine partly because of heat loss due to the small size of the engine.  Note that the numbers the Wisconsin group reported were normalized to 59% "in a truck engine." 

Sounds eerily familiar to what was posted by a farmer on the other forum years ago.  He swore up, down, and sideways that by adding 10% regular unleaded gas to his diesel, he was achieving crazy efficiency, like 50% more fuel left in the tank after he finished plowing, than with straight diesel.   

A number of you old timers might recall that George published on his website a couple of reports I wrote to him and Joel regarding my observations during the assembly of a kit-engine they were looking at importing.  Following a version update, the software George used on his website lost about half of the photos, rendering the report pretty much useless. 

Since I retired last Fall, I had time to revise and augment the original report, which grew from simply a "put 'er together and tell us what you think" to a more in-depth discussion of what I saw as I subsequently stripped that engine down to bare metal, and then slowly re-assembled it.

There are presently Part 1 and Part 2 on the Utterpower website.  Part 3 is in the works, so stay tuned.  George's new website is something of a blog.  Scroll down to Jan 18 and Jan 26, 2015 to see the links for the articles.  http://www.utterpower.com/

I hope the articles are helpful, especially to the newcomers who haven't been around these past 10 years (has it been that long?).

Quinn

Bruce, did your Gast air starter have any trouble cranking your engine when it was cold?

The Cap and Trade fuel tax is supposed to kick in tomorrow.  They say 12 cents/gallon at first (Kalifornia), but it is expected to increase thereafter.  Up to 76 cents/gallon by the California Air Resources Board's own analysis.  So enjoy your cheap gas while it lasts.

http://cafuelfacts.com/cap-and-trade-for-fuels/

Quinn

Ahh, found a manual online.  Regarding the funny little cups, apparently you fill them 1/3 full of regular lube oil and inject the oil before starting when temps are below -10 deg. C.  Purpose is to raise compression and to seal valves/rings with oil in case the engine hasn't been started in a really long time.  That factoid from a kind gent (Combustor) somewhere north of West Australia. 



[Edit:  In case anyone's interested, the manual is online at http://www.winget.co.uk/document/LISTER%20ST%20WORKSHOP%20MANUAL.pdf.  It's worth looking at in case you (like I), can't resist looking up the skirt of a new engine.}

Hi Bob,

The white plastic plugs, as well as the steel/iron holes they fit into have about a 1/32" diameter hole in the bottom.  Hole is cylindrical with a taper at the bottom, like it was drilled with a twist drill.  It looks like a liquid is meant to be poured into the hole.  Was thinking it might be an oiling point, but perhaps alcohol or starting fluid is poured in and dribbles into the intake port.  As far as the "cold start device that is screwed into the machined face above the inlet port," it's possible that I'm seeing only part of the setup.  I was mainly concerned that if it was an oil cup, I might be overlooking a maintenance item.

It's a neat engine.  Really sounds like a Diesel!

Re: building an engine, it seems the top end (cylinder/head/piston, conrod) are available for reasonable prices.  Alls you need to do is build a crankcase for it and work out how to oil the bottom and top end.  What we were talking about back then was making a horizontally opposed twin, like a BMW motorcycle engine, but only Diesel.  The balance issue would largely be mitigated by the opposed cylinders.  Certainly a project, but the Wright Brothers built their own engines, so nothing's impossible.

q.

Hi Tom,

I've never heard of anything like that on a high speed diesel, which the ST2 is.  I suspect they're oil cups since they have a small hole in the bottom, but I'm unfamiliar with the anatomy of the engine, so your guess may be better than mine.  I'd like to get a manual for the engine, but they don't seem to be available any longer.

q.