New guy with basic questions

Yup, be yourself. But don’t let your stubbornness kill your fun. Most of us on here have a bunch of unfinished projects. Most creative people do. I heard somewhere that only about 5% of J. R. R. Tolkien’s writings were ever published. Not surprising to me at all.


This heat recovery thing…it’s not crazy. At some point though, one has to examine the point of diminishing returns. I reached such a point yesterday while I was doing maintenance on my six kilowatt yanmar air cool diesel engine. I had bought a fuel filter for it 2 years ago and never put it in. I was replacing that, changing the oil, and cleaning the oil filter. I was doing this while siphoning methanol out of a barrel in order to make methoxide for another batch of biodiesel. In the last 2 days I have filtered and stored over 100 gallons of biodiesel/offroadiesel/fueloil/light distillates. This is 100 gallons of fuel that can be run in the little yanmar. The boys came out to the shop to see what I was doing, and I started the yanmar for them. I brought this home from iraq, and they have seen it all their lives but never really looked at it now that they’re teenagers they showed some interest in it. I let it run for a while, and then I put my hand on the exhaust manifold. It wasn’t even warm enough to burn me or make me uncomfortable. It made me realize trying to capture waste heat from this little engine was ridiculous. We could let this thing burn as much fuel as it wanted to and it was so efficient it would never make it worth all the effort to build the infrastructure to capture the exhaust heat. Seeing as the fuel is less than $0.10 a gallon, it made no sense to do anything but generate electricity with this and just let it go all day long.


Thats not what I was implying.

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It’s fortunate that I wasn’t addressing your implications then :wink:.


Right on Bruce, Yeah this month I have shut the shop down and been in design mode all month. Been working final revisions for the gasifiers. a new power generator and number of new kilns. Everyday this month Ive had to tell myself, hold on Matt keep it simple dummy. keep things easier on yourself.


I wonder if you could further that systems efficiency by adding a flywheel and a planetary gear set providing a 6 or 8 to 1 speed up between the motor and flywheel?? I believe it would be pretty simple to add?!?

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I hope you are continuing your efforts, building the machine that provides inside heating and charcoal as a by product. Is the charcoal close to engine grade?
This twofer stuff is how I like to roll.


Thanks for your interest in the old generator. I think something other than the venerable 10SI alternator might be the first step in improving efficiency. It gets hot, and frequently burns up it’s diodes. The trouble is, I have a barrel of them. It takes less than an hour to switch out a bridge, and put it back working…so I have been muddling along that way. I really should do a version 2.1


The kiln that runs chunks to lump charcoal yes. However the pellets I have not had enough run time to tell if it will be viable. I have had good success but there were a few times where there was some tar in earlier development. So I’m cautious yet. I will also be experimenting with a chip fueled stove technology and I hope to have beta units on market by end of fall along with my own proto here for my primary heat. Cant say if it will work or not yet as they only exist in concept and a CAD model.

CNC machine is broke waiting on a stepper motor drive so shop will be shut down until it arrives estimated in two weeks. Im hoping to have the first chip stove built by end of October in time for the cold weather to set in here in Mich. :frowning:

I bought a front end loader full bucket of chips; cost me $50 bucks I couldn’t give them the money fast enough. These chips are clean meaty hardwood chips. The nice thing is they are right behind the shop, They just drove the front end loader over here and dumped them here. There are literally mountains of chips back there.


Looking at your pulleys it looks like you may need to speed that alternator up a bit and put a larger pulley on the engine. But then again it depends on what your bank is pulling out of it. I use a 5 inch pulley on the engine with the stock pulley on the alternator and run probably around 2500 RPM . I think I have the 12SI but not certain. But my battery bank may not be pulling as much as yours. I have not had an issue with the lipos Im using.


Hello Bruce, diesel, unlike a petrol engine, has an inappropriately lower exhaust temperature and emits most of its heat through the cooling of the head and cylinder, but still with an engine like yours, at least 70% of the energy is lost in heat.


Exactly the things that keep me going. It is very inefficient to produce electricity from diesel or gas , let alone woodgas (another quarter is lost there). It is a good idea to capture the ‘lost’ heat and put it in a place you can use it again. A buffer is excellent for that. For me, still fighting the basics, and only thinkering about the final solution. Start with the basics and go from there. In our situation solarpower is very important and provides the major piece of pie. But when solar is not enough, we also need heat, so 1 + 1 = 3.


Is your BMS programmable? Can you limit the amps if you choose?
That’s the big horrible problem with the 10/12SI. They cannot help themselves, they give way more amps then the diodes can handle.
BTW, the voltage sensing circuit works at 7 kHz, so spinning them faster doesn’t matter. The rotor field can stay on at slower rpm and still make full power in the stator. That was the original purpose for the alternator to replace a generator.
My generator version 2.0 has double shives and a 1:1 pulley ratio. I have to turn the field off manually, when the bank is down really far, so it doesn’t stall the diesel. Then cycle it manually til it stops pulling so heavy.
Sorry, I rambled on and on…


Yeah we sort of hijacked his thread. Good info you gave and good to know as I plan to work a lot more with alternators in the future. The BMS I have is programable but not for current limiting. Could you pulse the field circuit rapidly? If so I could code an Arduino with a pot to fully that alternators output. It would use a big Mosfet to pulse the field wire. Maybe create a new thread for that.


I’ve been too busy reading to reply, but I appreciate the discussion.
I came up in the trades, as an electrician, so I really appreciate strait talk from those who know what’s up.
That same experience taught me that engaging the noggin and sharing whatever I came up with was part of the job.

I can tell you guys get that culture of sharing knowledge and bouncing ideas back and forth.

Thanks for making me feel at home!

Steve, I’m going to take some time to digest that gasifier build.
Ive spent a lot of time reading about rocket mass heaters and their proponents eschew burning long for burning clean.
It seems like the gasifier boiler might do both!

Bruce, I hear yah on diminishing returns.
I was considering a greywater heat recovery system, but even with the simplest diy system the math doesn’t pan out.

As similar thing happened when I considered switching laundry and toilet flushing over to rainwater.
The huge amount of water I would have need to store made me switch to more efficient toilets and cloths washers instead!
Now lf I do decide to switch these functions to rainwater, it won’t take a swimming pool sized tank

Matt , do you have thread about your pellet futnace?
I’m stoked to see how you separate the finished char from the uncooked pellets.
I actually don’t want to depend on pellets for my own uses, but its an interesting problem to solve.

Your chip furnace will be more my cup of tea, for the reason illustrated in your posts chips are cheap or even free.
I’ve used Chipdrop once and made direct deals with tree guys a couple of other times to get dump truck loads placed onto my grow lot.
I would gladly spend some winter days making char in a hoophouse using one of your designs and almost free wood.
Getting space heating and a refined fuel is extremely efficient, specifically in man hours, the most precious of resources.

So , another basic question, this time about
Must they be in direct contact with the coal bed?
Could they be just on the other side of a stainless steel screen?
For that matter, does there need to be a focused nozzle?
I’ll specify my question to charcoal gasifiers in particular, since I don’t know enough to know if it makes a difference!


Excellent “Eureka!” outlook JoepK.
Heat is not a waste if you were going to have to needfully produce it anyway.
When the clouds, rains and snow/sleet comes daily solar-gain declines but household/shops heat needs raise.


Great clarifying statements WilliamB.
Tradesmen are practical men, generally. Ha! We learn to be on our own stuff, having to please the demands of often very impractical designers. Just as long as they will pay-well for their demands . .
Our own stuff: we doing the paying. And a fellows time is the most dear commodity. Never squander it.
The Rocket process, and TLUD advocates have their merits in some circumstances.
Generally in low, and no space heating needs places and times.
My 100-Days-of-Summer has ended now. Clouds and rains now for 9 months. Needing whole house heating daily now. And especially interior house dehumidifying. Actual in-house wood burning give us the dehumidifying and flue-flow, drawn, forced air changes.
Remote outside boiler system cannot do these. Then needing electrical energy expenditures on dehumidifiers and forced air exchanging blowers systems. So’s not to inside molds and have bad respiratory problems.

On the wife acceptance thing . . . .
I long delayed getting married for reasons. One was finding a wife who would accept in-house woodstoving. Ha! Finally found a gal who had also delayed waiting to find a fellow who would work the wood to give her in-house woodstoving that she had grown up with. I t was our 28th anniversary last Saturday. Ha! We both forgot it!
(Advice to younger men and woman. Basics Practicalities first. Then love will grow.)

Do you prefer WilliamB.? Ronyon? Or another?
Do you prefer SI (metric), or Imperial/inch?
Steve Unruh


If you are building a TLUD you are already building the design I use. Except I close off the top of the fuel hopper and force the pyrolysis gas out the lower vent holes where it can fully combust lower. Then use that to heat the outside of the hopper to more effectively heat what’s inside the hopper. The grate is the air intake and it simply a very loose and passive. How passive it is determines the fuel you run. Pellets you of coarse would have smaller holes. Chips bigger holes, chunks it changes to a bar grid. As the fuel reduces and becomes brittle it falls thru the grate. Put something there to catch it then seal it off when full. You can put a bell over the top for indoor use and install a chimney onto the bell.

This is nothing more than a TLUD stove but with a closed top. I dont really know why a TLUD is called a TLUD because its primary combustion process is not at the top its at the core where air first enters at the grate. The gas at the top is secondary gas this is lit and once that process is established the fuel is not actually what is combusting its the gas flowing up from the bottom and out the holes you drill in the top portion. My design I simply ignite that gas as it leave the primary combustion stage instead of at the top. Its much more effective this way.


I’m wondering how well the system would work with a hot water heater tank as the core. The one I got for free has a rotted bottom so I could use that as the open bottom, and cut out the top with a lip as my lid. I have tons of solid 55 gallon drums that I can’t do much with except use for making my charcoal, so the outside would be the same as yours.


I would imagine it would work better than the barrels as its thicker steel.

To make this work better insulate the outside and I think if you double stack that will really boost the efficiency as the fuel will have longer time to cook while the combustion gases will have a longer path to heat the hopper.