I have a gasifier design that works well and would like to pair it with an engine / generator that I don’t have to see how the system runs
I am wondering if anyone out there with a small generator set up for wood gas would be interested in collaborating on testing
What I have set up is pv solar panels that heat a retort that has a lot of insulation. The insulation ensures almost all the heat goes into the biomass. 800f. Plus or minus. Wood gas comes out via a tube and goes to a filter or ? Then to the engine.
I am interested in this for a couple of reasons
A lot of the energy from wood goes to electricity not heating the wood
2 it is a way to store excess pv power without expensive batteries. By making wood gas during day and then using it to run generator at night
3 and it is an interesting way to get power and charcoal out of biomass with minimal smoke etc
A wood gasifier is not a replacement for solar panels. Get the solar panel system first. This is at best only good for solar power back up. A gasifier engine system is a lot of work, this is far from free. Can it be done? Of coarse!! But thats if you have to store the energy not waste it by running a generator as a primary power mover. Storing the energy versus using it direct from generator is about 4 times more efficient using it in combination with battery storage. Even then this will still be a lot of work daily.
Theren are no cons to battery storage only the pros. Cost is irrelivant if you want something thats actually going to be viable.
Pros:
4X more efficient
Only power limitation is the inverter you use; instead of a very limited gasifier engine system.
You have back up power for when things go wrong.
Clean power. even inverter generators cant do this on woodgas. They fluctuate too much.
Higher Eficiency = Way less work you need to do = living your life doing things not wood related
i agree with Matt.
battery is the central and most important component of an off grid system.
it would be very hard to manage system without a buffer where you can feed in and mix energy from
various sources and take it when and how much you need it.
10 years ago lithium was super expensive so practical battery options were some version of lead-acid and they were all BAD Low depth of discharge, low power density, low cycle life. The cost per watt*hr was low enough that you could almost go off-grid but it came with huge compromises. You would need to reduce your power budget to an absolute minimum first, then build a system to address that limited need. Inverters were pretty crappy so 12volt circuits and appliances were desirable, thick wiring and all.
Today lithium iron phosphate (LFP) batteries are affordable, powerful and long lived. Inverters are good enough and clean enough to power regular appliances. You’ll still want to keep your power budget restrained but on-grid lifestyle is possible off grid if you want to spend. A version of on-grid lifestyle is possible on a tight budget. Solar is the key to all of this. Per watt solar is cheap-cheap-cheap. The downside of solar is that it only makes power when the sun is out. With batteries and appropriate backup, this is not an issue.
You want woodgas generators charging batteries only as a solar back up. Unless you intend to run a generator 24/7, you’ll need batteries anyhow. Once you have batteries, you might as well throw some solar panels in the mix. Once you see how much power a quiet, easy $200 solar panel can produce, day in and day out… you’ll want 10 more and then 10 more after that. Better to plan in the first place for where you are going to end up anyhow.
I’ll just add to this. Overpaneling is cheap power. Buy more panels, they’re cheap. You can use the extra solar panels to reduce your battery needs, if you find ways to load shift. Don’t ask batteries to drive resistive heat loads or large motors if possible. The extra daytime solar can drive loads directly. For example, use some of your panels to directly run a DC mini split like this one, let it run when the sun shines:
Use some of them to heat up water for domestic use. Or, expand that idea and use the hot water for radiant heating in the floor. A large insulated water tank will store a ton of solar power as heat. I know thermal solar panels are more efficient at collecting heat but they cost a lot more than PV, and are inflexible (they only do one thing). Summer comes around, you’d rather have electricity than more heat.
If you really want solar to assist your wood gasification, set up a high-tunnel / greenhouse with solar to run fans and operate ventilation flaps during the hottest part of the day. Store all of your wood in there and it will dry extremely quickly over the summer. This can be firewood and wood chunks for gasification.
I am building an offgrid house myself and I plan to incorporate all these ideas. But I’m still going to have a large lithium battery bank, because it makes sense. They too have gotten cheap, not as cheap as panels but very affordable. For well under $10K you can get enough batteries to get a normal efficient household through a cloudy day. I plan to add more over time, but it’s a good start.
For a look into maximum PV solar build-outs subscribe and follow Curtis Stone on his fully off-grid homestead:
This is #3 of a two years ago six part series.
Him and his family live interior BC Canada. Not exactly an optimum PV solar location.
Yep mondo PV arrays now. Huge battery bank. With a commercial grade diesel electric generator as his back-up fill-in.
Yeah. Purists give him a lot of shit for his diesel fuel usage. Watch, listen to his reasoning on that.
Nope. He does not woodgas.
But I’ll say Sailordan by how we all are striving to make fully “thermal-chemical reduced” three-fuel gas blends from wood . . . you do not woodgas either by simply cooking wood in a retort.
You are producing a mix of heat driven off pyrolysis (smoke) gasses.
Not a mix anyone will want to run through their IC piston engines.
I build gasifiers with gasoline. lol. I have no problem with gasoline or Diesel, Im using it while its there. Im building for a time when becomes not there
First, I 100% agree with what Matt was saying. You want batteries. You already have the energy in the form you want, you are just trying to timeshift it, and firm it up.
Roundtrip on batteries is around 90% and end up cheaper and easier then running an engine.
What you really have is an electric charcoal retort. It is called wood distillation. It is a pot still. The products of wood distillation are char/ash, and gases that come off.
The gases are typically condensed off with a simple condensing loop. You still end up with a gas portion that is burnable, and a liquid portion. The gases are burnable, but you have to have a pretty big retort to get enough useful for an engine. The liquid portion can be further separated with fractional distillation or letting it sit for months (as in the case of wood vinegar) Fractional distilllation is separating by condensing temperature so basically anything that condenses lower then water, water, and then what is left in the pot is your tars. The fraction that condenses lower then water will contain methanol and maybe some ethanol, which can burn in your engine. The larger issue is methanol and ethanol are miscible with water and there is a limit on how pure you can get with simple distillation. And I do not know if you can get it pure enough to run in an engine. Pot stills like moonshiners use can only get to like 75% reliably depending on the relative humidity of the air.
you can make a charcoal gasifier to use the charcoal portion,
With an electric, I would be more tempted to do thermal decomposition of plastic to oil but you don’t get much fuel that way either because plastic has a lot of air in it, and you are still doing all the fractional distillation parts.
Transportation is an issue, so it would help to know where you are located.
It’s possible, maybe likely, that there is tar, moisture, or other stuff in your gas output that would be hard on engines. Filters will get the particulates, condensing can get most of the water, and some of the tar. Any tar left will be bad news. Is there any brown, sticky stuff in your outlet tube, or any water?
