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.
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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.
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Matt,
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…
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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.
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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
nozzles.
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!
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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.
S.U.
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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?
Regards
Steve Unruh
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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.
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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.
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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.
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I was thinking of preserving the solid bottom of the 55 gallon drum and flip it upside down, with the hole cut just big enough for the lid of the core to easily fit through, former top would just be removed entirely since the bung holes aren’t helpful. Would give a damper/baffle for the heat to dwell longer. I could also just add an afterburner but if I’m making it to keep refilling over and over I wouldn’t want to handle a red hot barrel, haha.
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Build it an for sure explore new ways to do it! Post pics!!
For the barrels put eye bolts in them and use a hook to pull them out and of coarse wear gloves. But they are not that hot, the charcoal cools faster than you think. Your replacement barrel will be cold. I now have a guillotine cut off plate I install to block off the fuel from leaving the grate while you change the catch drums out.
If you do a removable catch bin you must enclose it do not catch the woods on fire!!
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I’ve seen your catch barrels and I’m not too worried about how hot those would be, but I meant using another barrel as an afterburner would be pretty dang hot to remove each time I wanted to refill the hopper. Though with a hot water heater tank I would get a good 40 gallons of space per batch so I could make it a Once a Weekend type ordeal with one or two batches. I need to get a reserve of charcoal in case I need to power my little generator.
I live in the boonies so I don’t get smoke complaints luckily. I think they’d rather smell hardwood burning than garbage like some people still do around here.
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Ah ok I got ya now. Yeah I wasn’t thinking of removing, just a small set of steps to get up there to load her up. Yeah here Mi we dont have issues like other states do. Plus Im out in the middle of nowhere too.
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I’m already thinking how I can use water heater tanks to emulate Matt’s furnace.
Since it uses three cylinders, I think at least two of them can be water heaters.
I’ve found a plumbing supply house that will give me scrapped waterheaters for cheap or free.
Barrels are about 15 bucks, with lid.
I don’t like dealing with the paint, so I’d rather get a third water heater tank for the outside, but the bigger ones are harder to come by.
Matt, I’m hoping make a smaller version, to make sure I have the gist, and to use for cooking.
To that end, is there any part of this furnace that could be made in aluminum sheet?
Also could this design be built as nesting boxes instead of cylinders?
I go by a lot of handles, but Will is fine.
I’m old school American I’m my measurements but I can understand metric.
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I dont know about aluminum. Aluminum and copper will dissipate heat faster than it can absorb it. The primary function of this kiln is to do just the opposite and retain as much heat as you possibly can.
There is no right or wrong way to do this. Build it and experiment. The function you want to get working is getting the second stage to combustion upon leaving the side vent holes while sustaining primary air intake flows in through the grate. Once you have this you have basic concept working. What you do with it after that is up to your own imagination.
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I was only thinking about heat resistance, not retention/ dissipation.
Definatly gonna study your thread more, thanks again!
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I agree, I think it could be done. But considering practicality. It takes time to get things working and started and operating and adjusted. I can not think of an application for starting an engine for 10 or 20 or maybe 30 minutes only. I guess in some really specific situation trying to charge some batteries etc… I think I would get frustrated by the amount of time and energy spent to make an engine run for just a short time before the quality of the gas changed and I’d have to be making constant adjustments.
aLSO, will it still be a TLUD once you apply vacuum to it to remove the gas and move it to the engine?
With that said, if anyone knows what he is talking about…it’s Matt above.
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Well no, when the burn has made its way all the way to the bottom a tlud becomes a charcoal brazier, If you want to argue semantics. I didn’t think we were into that around here.
My water heater tlud was not imagined to be a char gasifier. And though it would probably work for a short time there are much better, simple char gasifiers to be found on this site. I made one based on @k_vanlooken’s Some School In Thailand thread. It will supply gas to my 3KW genset for about a half hour. I take the charcoal I made in the tlud and put it in there. There needs to be ~24 inches of charcoal above the nozzle to make good gas. I plan to make a new one with a larger diameter and a 5 gallon hopper above the 9 inch diameter 24 inch long pipe. I plan to insulate the inside of the pipe with an inch thick ceramic wool blanket. I hope this rig will give me two and a half hours runtime.
Rindert
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I made a new thread to solicit advice on the tlud boiler.
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