Micro CoGen.

No easy answer for you sorry. You could split up your panel into two, one utility, and one generator. Or use a battery bank and inverter to feed your main panel, then charge the bank with your generator, and a grid tied charger. Yes you will have expensive batteries to maintain and replace, but you gain all of the benefits of uninterruptible power. Without being grid tied (back feeding), it is my opinion that a dc link is the best option. You don't necessarily need a ton of battery capacity, just a dc link, I plan on doing this using ultra capacitors, to see if I can avoid chemical batteries. If you plan on having your generator running constantly you don't need batteries or caps, just rectify dc then straight to your inverter.

Well, been working a bit on the start of the build. The plan is to mount the genset on a leftover harbor freight trailer that I have. I will enclose and insulate this trailer.  I'm in the process of welding all of the joints solid because with just the bolts it's as flexible as a gymnast. I also pulled off the radiator and fuel tank. Any good ideas on how to build the coolant plate? Hot on one side with a 210* thermostat, cold on the other?

We'll done! Keep the updates coming.

should be able to get 240 and 120v. Can't tell you much more than the obvious, it's a four pole unit. Probably similar if not a st type.

thomasonw,
Thank you for the links, actually I was aware of your work and had bookmarked them already for a good starting point. As far as controller boards, at the low volume of generator setups I will be creating (one at a time). Soldering boards together is not too terrible, also I already have a handful of arduino uno's laying around. Please post up any info on your progress reguarding these controller boards though as it does interest me and others here.
Thanks,
-Focodiesel

This technical "Alternator Bible" is geared more for automotive applications than power generation and it focuses on the delco-remy units, I know most of us try to avoid using these alternators because of their poor efficiencies, that being said, there is a lot of good knowledge in there so I will post a link anyways.

http://www.pirate4x4.com/tech/billavista/Wiring/Part2/

Quote from: mobile_bob on January 04, 2014, 08:09:52 PM
some thoughts and a few answers to your questions

to my knowledge the 1100's are  direct injected, and are some of the most efficient of the chinese horizontals.

the st self excites because of the residual magnetism in the rotor core, sometimes this is lost and you then must re excite by flashing the field, but in my experience this is rare.

yes an st could be regulated to generate at varying speeds, however it cannot do so and produce 60hz power.  if you run slower you will have lower hz, higher speed will make higher hz of course and is likely unwise for various reasons of safety.

Could you elaborate on why an st gen would be unsafe for variable speeds. ( I would not exceed 1800rpm, so lets say 800rpm-1800rpm)

Quote
recheck the L1, L2 etc, they may have connected or jumpered the center connection to the chassis/frame and this will show as a short to ground... it might be connect at the breaker box that way or who knows where... best to separate all leads and recheck so you know there is no connections to ground/chassis/frame/box or whatever.

the st might not want to restart up if the slip rings are corroded, likely the case if it has sit around a long time unused, and the field might need flashed.

Thanks for this insight, I will try all of these steps.

Quote

i have tested the 555jho at 48volts nominal, while it will make the requisite 58.8-60plus volts needed to charge and equalize a flooded battery, early testing results have not been as efficient as i would have liked, at least as compared with the same alternator doing 28.8volts charging (24volt nominal).  baring in mind the rectifier bridge was upgraded to 200piv rated diodes to allow operation without blowing out the oem 12volt nominal diodes.  i need to do more work to quantify the results and write up another white paper or an update to the original.

it might be that twin 555jho's charging a split battery bank would be the most efficient using this alternator for 48volt nominal use, that is something i also can test but have not done extensively yet.

Please do put out a 48v white paper, I know myself along with many others are waiting eagerly for such a document. Also, thank you very much for your first whitepaper and all your other contributions to the diy/ cogen community, they have tremendous influence.

So is the larger rated diodes the cause for the losses? I would have thought 48v would have been more efficient...

Quote
optimally the use of one alternator would be most desirable for not only obvious reasons, but also because the output capability is higher, at least in my experience in earlier testing.

So do you think I should use the st-8 which is direct coupled? I would think trying to get 50v at 800rpm would be less efficient than with two belt driven 555jhos at 50volts each paralleled. Also the 555jhos were designed for variable rpm's, st's are not. What are your thoughts?

Thanks for the help,
-Focodiesel

Quote from: glort on January 05, 2014, 03:32:12 AM

For the land of the free, You sure are an over regulated, carefully watched bunch.

How is the audit going to be averted if the OP generates his own power by whatever means and doesn't get screwed over sufficiently... Errr, I mean , use enough power anyway. If his consumption drops, won't that bring up a red light on the gestapo's computer?

What do you guys in the states pay for power anyway?  I hope it's not like fuel where you all get upset about only paying about 60% or less than the rest of the free world.

Sadly, our brainless politicians seem hell bent on sending us down the same path of big brotherhood.  Forced to pay through the nose for everything and no free choice of how you live.  Out here in the backwoods, It may still take a while though.

currently my provider is a private corporation and not a municipality so I'm hoping there will not be too much trouble getting them to pull their meter off my property, but you never know in this crazy world. I guess I will deal with that hurdle when I am ready and have a fully tested and operating system. The sooner the better though because the amount of laws and regs never shrinks...funny how that works.

Quote from: glort on January 04, 2014, 05:55:48 PM

I know the voltage is lower than ours but I believe you have 3 phase at every outlet so that again simplifies things dramatically. Just work out what you can run and get an appropriate size motor.

No we only have three phase in commercial and industrial applications, Currently I have single phase. Grid tie'ing was brought up in my first thread http://www.microcogen.info/index.php?topic=3219.0 . Over here there are digital smart meters, and enough regulations and fees to make your head spin, that is why I will go off grid, even with all of the benefits a grid tied system would have.

-Focodiesel

Well guys in an appeal to limited time, and just the fact that there was a changfa s1100an genset locally on craigslist, I will not be trying to convert a yanmar clone to water cooled, at least not in the near future. I still do like these little yanclones and see myself repowering all kinds of lawn tractors and other portable power units with them though. Great little engines for what they are, a light, air cooled, affordable engine.

Anyways I started a new post to get your opinions, and to document the build of my chp system utilizing my new water cooled changfa. Please go to the "Members Projects" section and check out "s1100an changfa, chp, variable speed/output build thread" or just click here: http://www.microcogen.info/index.php?topic=3264.0

Thanks,
-Focodiesel

Hello all, I am in need of your collective brainpower to help me design and figure out the off-grid setup I will put together in this new year, the goal is to have it running before next winter to ease my utility bill pain. Some of you saw my other post under the changfa/redstone/chinese diesels section, "yanmar clone...slow speed water cooled conversion".  After finding a local changfa type generator set on craigslist locally I had to buy it, this was the first one I've seen locally and not having to pay freight is almost a reason to buy in and of itself. I would like to get as much advise on how I should accomplish my goals with this so please comment and share your knowleadge. I will post regularly here with pics and vids of my progress.

What I'm starting with:

The generator I just purchased has a "changfa" type horizontal water cooled single cylinder engine. It is a s1100an built by Chianghuai Engine Works, I believe the build date is 1999. It is rated at 16hp @2200rpm. The guy I bought it from got it with the house he just bought, it was sitting under the deck. In this small world, it just so happened that my buddy lives next door to this guy, and helped him get it running, so lucky for me I knew the inside scoop on what it took, The engine was stuck and they removed the head and had to hone out some rust, but put oil in, head back on and she fires up. I need to verify whether it is DI or swirl.

http://www.youtube.com/watch?v=L_p8nhGAJYI

The generator is an 8kw st type, Shows no voltage when it is running. It looks pretty weathered and dirty inside, The armature windings are shorted to ground so if it is salvageable it will take a thorough rebuild.

Currently I heat my water with propane, and space heat comes via electric baseboards (about 4kw). Average electricity consumption not including heat is 1kw. This includes fridge/freezer, electronics, microwave, range, oven, lights, etc. The catch is, within this average load are considerable peak loads such as welders, kilns, oven, motor starts...

I have a good steady supply of wmo, and eventually I would like to build a gasifier to fuel it with as well.

The Initial Plan:

Scrap the ST Gen in favor of a pair of 110-555jho's or whatever mobile bobs latest 48v concoction requires. and drive with a serpentine belt. (although if you think I should go st with split armature to make 48v than convince me, but I don't know if that would be viable with variable and lower rpms). Use an arduino microcontroller to control engine throttle/speed and excitation for the alts, and anything else that is currently being done by others with balmar controllers. Possibly do a lead/lag setup to have only one alt running for lower loads and bring the second on when necessary. I would like to not use traditional batteries at all, instead I will have a 48v nominal ultra-capacitor bank. I am thinking of using two Magnum Energy MS4448PAE inverters paralleled to give 8,800 VA continuous and 17kw surge. I want this system to be flexible and have the ability to vary rpm per the demand, with the lowest demand slowing the engine back to 800rpm or so similar to what veggie has done on his slow speed changfas, so added flywheel mass may be needed. I will add a hydronic unit heater (radiator and fan) to my living space and one to my garage. Plumb the engine water jacket into the heating loop, which will include a heat exchanger tank for domestic hot water (replacing the propane heater). Add an electric water heater into the loop as well to add load and heat if needed. I am thinking a small noise shroud around the engine, than a larger one around that, than the building walls. Hopefully three sound barriers will lower the noise to keep the neighbors off my back. Make and/or install an exhaust heat exchanger. Down the road tie in a 48v PV system to keep the gen from running in the summer.

Well after writing that all down, man do I have my work cut out for me this year!

I guess my first questions right off the bat are:

1. I have done quite a bit of reading and have come to the understanding that ST Generators are self excited, meaning they can black start. Could someone explain to me how this happens? There aren't permenent magnets in the generator somewhere for exitation correct? So if there aren't pm's what creates the initial field?

2. Can ST generators be controlled to generate at varying speeds? or am I going the right direction with the modified leece neville alts?

3. The armature windings on my 8kw st (L1,L2,L3) should not be shorted to ground correct?

4. Has mobil bob or anyone else done a 110-555jho @ 48v yet? any posts, white papers on that matter?

5. Does anyone have clearer copies of the changfa engine manual that you could send me? I downloaded one from here but it is pretty blurry.

Thanks everyone,
-Focodiesel

Quote from: Dualfuel on December 18, 2013, 06:29:31 PM
Ahhh, let me clarify. Lets pick your 40% thermal efficiency....meaning 4/10ths of each gallon is converted from heat to work....the other 6/10s is wasted heat....of that wasted heat, 90% goes out the exhaust.

Yes I understand what you are saying, but I think you may be incorrect about your 90% statement, I have typically heard 2/3rds of combustion energy content is converted to heat, half conducts through the cylinder to the coolant and/or air , half goes out the exhaust, or as common rule of 1/3,1/3,1/3. I think it is important to clarify this.

Quote
But don't get hung up on the numbers....what is important is the idea....you have to ask yourself...at what percentage is it actually worth going after the fin heat? You intuitively know that most of the available waste heat is already in the exhaust gas...

No, that's where the confusion was, I did not intuitively think most of the heat was in exhaust gas, It is very reasonable to think there is a sizable amount of heat lost to conduction when you observe the size of radiators on liquid cooled engines.

So if there is equal heat lost to exhaust and conduction, It then comes down to what is easier to harness, In my eyes it is a liquid cooling system, once that has been built, than try and go after some of that heat in the exhaust.

QuoteThermal efficiency is purely theoretical, AND saying 40% is converted to work, is not actually describing what work is being done...for example, blow-by is work, keeping the metal expanded due to heat is work, pumping lube oil is work, friction is work. None of these are of any value to your heating measurements. 

No, no...thermal efficiency can be very specifically described, calculated, and measured. it is not arbitrary or subjective. The "work" is power produced off of the crankshaft. I don't quite know what you mean by blow-by and keeping the metal expanded due to heat as being work, but as for pumping lube, yes it takes power but ultimately parasitic loads turn into heat, sound, or some other form of energy, and yes these "lost" loads are factored in to thermal efficiency mainly turning up as heat. Friction, again mainly turns into heat which is conducted away into the coolant/air.

QuoteThe number that is valuable to you is the brake specific fuel consumption. Knowing how many pounds of fuel your engine uses per hour can be found using the BSFC chart for your engine.
Ball park numbers for what you  need can be found at the Beckett Oil burner site...typically .4 to 3 gallons per hour.  Good BSFC for a yanmar is .4 lbs/hp*hour  so 2 lbs/hour for 5hp.....so you might be coming in low at 5hp, seeing as 2lbs is .3 gallons.

Good to know, thanks I will look into that.

QuoteThere in lies the rub....my engine will not actually burn enough fuel to make it worth setting up a heat exchanger for a house. Perhaps heating a battery room would be more practical, or heating the wood shed...but unless I start burning enough fuel to operate an engine somewhere above the 5hp output range, it simply would be an auxiliary, which means I'd be burning wood anyhow.
Its a very interesting problem in itself, with most of the data available through the internet and ASHRAE. I think the problem becomes moot when you do a cost benefit analysis on the money spent versus heat input.
DF

You may be right, your engine may not be ideal for heating your place, for me, 4 kw of heat is very attainable through waste heat capture. Another strategy I will employ is to have an electric water heater in series of my hydronic system, if there isn't enough heat output from the prime mover, and spare power capacity, you add the load of the heating element, further heating the water directly and loading up the engine which will in turn create more engine heat...

As for the cost benefit analysis, that has been covered earlier in this post. If we didn't factor in the enjoyment of creating, tinkering, and engineering this stuff and actually calculated the "labor" costs, none of us could justify this stuff. But that being said, there can also be huge savings, If I eliminate my utility bills, that is a substantial amount of money, and how can you put a price on freedom, or peace of mind?

Quote from: Dualfuel on December 18, 2013, 04:44:18 AM
You know.....before I'd go through the trouble of etc., etc. I would do an experiment with the engine exhaust...the various combustion classes I have been in, all are fond of saying that 90% of the heat goes out the exhaust....perhaps the 10% coming off the fins isn't worth the effort.
Another thought is that, regardless of what percentage is lost through the fins...you must ask yourself what heat is actually available. For example, my L40 offers 2.8kw continuous so pretend its 20% efficient and divide 2800 by .2 and you can see I'd have 14000 watts available for heat. Now for my situation, that probably is enough. If you are wondering about yours, either learn to read your natural gas meter, or fire your furnace on a 20lb cylinder sitting on a bathroom scale to find out how much fuel you are burning in an hour. Basically, heating your house is all about how much heat your house rejects (or loses) per hour. The question is whether the engine will actually be burning enough fuel to come close to the amount of heat your home is rejecting.
I have been saving exhaust heat exchangers for years, for the purpose of one day installing them on the L40s. I have yet to bring myself to go through the trouble because I actually live off grid, and do not enjoy the continuous rattle of a generator. Where as, a wood stove or an oil space heater is silent.
anyhow, this time of year is perfect for armchair speculation, and lots of interesting ideas come out of it...
BPJ

I think diesels are closer to 40% thermal efficiency so in that case let's say 7kw heat for your example. I actually currently use electric heat so it's easy to figure out what it takes on the coldest days (a week ago in CO) about 4kw will keep it warm. Also are you sure about the 90% exhaust heat statement? I have always heard about 1/3 exhaust heat, 1/3 conduction heat, 1/3 kinetic power.

Quote from: Thob on December 17, 2013, 10:23:50 AM
I can't remember where, but someone on these forums suggesting using a radiator to capture heat from an air cooled engine.  Hot air from the engine is director thru the radiator, heating the water inside which flows to the heat tank/storage/etc.  I have no idea how well that would work, but it sounds much easier than attempting to get the right water flow around an air cooled engine.

I would think that the heat transfer using that method would be far less than that of a water jacket, but I may just duct the heated air into the space to get chp out of an air cooled. But ultimately I want a liquid cooled engine because hydronic heat is much easier to utilize (pipe vs duct).

Quote from: veggie on December 15, 2013, 07:40:16 PM


What will you be driving with your engine? This may help in determining the best engine for the job.

Very cool setups veggie thanks for sharing, I was already one of your subscribers on Youtube!

As for the alt, I was thinking a 555-110jho, 24v mobile bob style.