Woodgas for Generator from Pizza-Oven?

Hello folks,
i just created an account here. I am living Off Grid since 2014 and my energy is coming from Solar only since then.
Artificial clouds weren´t an issue back then, but now in 2024 this “situation” is that bad, that i can´t gain sufficient solarpower anymore.

I builded four wood ovens in 10years and now the fifth oven in my 300sqF House- a Brick-Pizza oven thing…

My question is:
would it be possible to cool down, purify, and then use these gases like with an Wood gasifier does? To power a gasoline Generator without carburetor and so on?

i am sorry for grammatical failures, my native language isnt english,

Nice greetings,
Andre

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Welcome to the DOW Andre.

When the pizza oven is heating to make pizza I think NO. You need the all of the woods energy to boost heat cook.

When the pizza oven is not making pizza you could use it to convert wood into wood charcoal. Then interrupt the charcoal from burning up. By hot removing that made charcoal and water douse quench it for later use in a charcoal gasifier to fuel the engine-generator.
Many here doing this type of wood charcoal making for an engine fuel.

See the top of page tool bar and open up the stacked-papers icon tool.
Read view many of the topics for Small Engines; and Charcoal Gasification.
Regards
Steve unruh

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Hello Andre,
Welcome.
Could you share pictures and perhaps sketches of your pizza oven? I have seen one very big, wood fired, pizza oven that was used for a restaurant, but I think yours will not be the same.
I think it is not difficult to make charcoal, and then make electricity from it. Here is a link to some of my experience.
Rindert

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Welcome Andre!

If l understand right, you are thinking to use the smoke/exhaust from your oven to power the engine? In this case, no. Woodgas is not smoke, but its true many people l meet think that.
Only practical way is what Steve sayd. Collect the embers when you are done baking, cool down and use in a gasifier.

How practical this wuld be, l dont know. Here, traditionaly, wood was all used up. Ovens were fired once a week. First they were heated for a couple of hours, then the fire was left to be burnt out. First, when the oven was hottest, flatt breads were baked (think pizza, but toppings were usualy just lard/cracklings, sour cream, cheese…). Then came the bread, a whole weeks supply, and latest were Mlinci, a kind of flat tortillia that gets dryed by the residual heat and then used like pasta, usualy just soaked in hot broth. At this point, the oven is preety much cold and the fuel all gone…

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Well there is this thing Im working on. But this is pretty elaborate for making Pizza.

The development goal was to build a gas storage for home gas. However liability concerns with carbonmoxide has made me reconsider this. So this will be remarketed as a system for specifically running small ICE engines from a very large gasifier that is designed for running larger engine applications. So this add on will make a large engine gasifier capable of running a small engine application that it would not normally be able to fuel. This is because small engines would not be able to drive a larger gasifier to tar cracking temperature parameters.; This system uses a very high output blower that will run the gasifier at its optimum opperating parameters as it will pull a static load on the unit. This way gas energy density will be more linear and clean.

This is the system that is going to make my company.

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Matt, what you have done is to make a fully automated gasworks in miniature mode. The Seattle’s gasworks was huge and supplied gas for thousands of people from 1909 to 1959 all done by man power no real automated workings just men operating it 24/7.
Good job.

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Hi Steve,
thanks!
I slowly understand… Good advice with the charcoal and the Small engines section!

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Hello Rindert, Thanks!
Yes I will attach pictures of this oven, i had it outside the house then a few days ago i dismantled it (just bricks and earth) and now i rebuild it in the semiBasement in our House.
The Platform is Done on 110cm of height.
Thanks for the link of your Generator Setup Post i read it later on!

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Hi Kristijan, thanks!
Yes you understand right and thanks for clearing up my misunderstanding.
I understand more and more the benefits of Good thermal mass/ insulation ratios and resulting efficiency increase. Or “more time to bake after the fire is out” so i will insulate the oven with Perlite(less expensive than ceramic fibre)…

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Thanks Matt for further information and experience in this direction!

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They wont let me upload more than one picture because im a new member the system says…

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Its only for the first post. Later you can upload as much as you want

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…so i can just add one picture in a post because i am a new member.

but ok later on than maybe.

My summary now is, that a pizzaoven type oven is the most economic to use for your back and knees(my rocket stove is on the floor and i dont want to use it anymore bacause of this…
But these Pizzaoven type is quite inefficient, right…!?

Would it be possibly to heat a Pizzaoven with woodgas?

My main goal is it to use a Oven like this…but i dont like it to see ~70% of the wood-energy out of the chimney…

If it is not possible to use the exhaust of a oven like this, would it be possible to at least afterburn the exhaust?

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Again NO.
Once completely all wood combusted you only have stable no-energy gases. Carbon dioxide. H2O water vapor.

Interrupting the complete combustion as in. a woodgasifier; or stealing out the made wood charcoal and that then only partially combusting it in charcoal gasifier you have resulting energy capable gases.
Carbon monoxide.
Hydrogen H2
And some made methane CH4
S.U.

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Your not going to gain anything, You will lose energy in fuel process as you are not going to use fire wood. Much more process involved to make the fuel. Then you lose 30% in the gasificaiton process. Then more losses gas cooling. You might end up with some energy gain but is it worth all the complexity and extra effort?

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Generaly l wuld agree with Matt and Steve, but here l think it wuld actualy make sence. Sometimes more refined fuel does make it cheaper, more efficiant in a long run.

I never understood why African people use charcoal for cooking. The wood is scarce. Now you want to throw half the energy away even before you start cooking? Made no sence to me, untill l built a charcoal cooker my self. Itsjust so much more efficiant. In the end it consumes a lot less wood all together thain if it were to burn raw wood.

In the case of pizzas, you want extreme temperature for a short duration of time. An insulated oven with a woodgas flare inside? I think its not a bad idea. Not a beginers project thugh…

Also, if baking a few pizzas fast and efficiant, then cool down, that makes sence to me. Burning ut for hours to also make beread and such makes lutle sence to me. Better just burn the wood directly

Edit: yes we loose 30% or so energy with gasification but thats with runing engines. Gas needs to be cooled. In a scenario like this the gas can be burnt hot. Its more like a gasification bolier…

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Perhaps you can simplify your project goal to be a smokeless, wood fired pizza oven? This might be a very good goal, I think.
Rindert

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What if you heated with the excess energy from the char making process? If he is off-grid chances are he has a use for biochar if he doesn’t want a charcoal gasifier.

If just wood and efficiency is the issue, then the smokeless firepit types of burners with the secondary air feed like the solo stoves seems like it would be a good choice for short runs.

Otherwise, I am almost at Matt’s idea but thinking that Foundry that ran off a gasifier.

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The way a gasifier works is it is limited on how much oxygen is aloud to enter the system or firetube area. With the high heat CO2 and H2O is stripped of it oxygen atoms that is what we call chracking it. This happens when passing through the hot Charcoal bed in the firetube and then cools. This does not happen in a open fire with lots of oxygen present. The Charcoal if left alone will trun into ashes. But if you remove it when it is just glowing Charcoal and remove the oxygen it will cool and quit burning quenching in water does this. Now you have what we call engine grade fuel for using in a Charcoal gasifier.
Like a simple fire gasifier or a down draft gasifier. These will make good gases to run a engine on.

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If you want to build a gasifier, you can, you just need a ‘startup flare’ which will require a fan or pump to move air. Usually we use the engine as the air pump except for startup.

You can knock out the idea for the guy that made the foundry… I remembered he actually used a bit of propane as the ‘fan’ a lot less then he would have without his gasifier, but it still used propane. I think he said you could use compressed air as well but it didn’t get hot enough fast enough for his demonstrations.

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