Gasification boiler or regular wood burning boiler?

[jerseykat1]

as the subject says next year i am considering an add on to my natural gas unit. Just keeping the gas boiler inline for back up.

what are the benifits of a gasification unit vs a non gasification unit?

my main concerns are not having to baby sit it. i would like to be able to load it 1 or 2 times a day maybe less if that is at all possible, it should be atleast 80% efficient, and no smoke too annoy my neighbors (i dont mind smoke for a about 10 minutes or so on fist fire up).

gasification is pricey and non gasification is not so pricey. i have a 1500 sqft ranch in north jersey. my current system is circulated hot water.

 

[woodmeister]

Gasification - you won't get the longer burn times but you will get the effiecienty and no smoke issues while burning less wood.

 

[muncybob]

We load our gasser 3 times per day as a typical burn is about 8 hours for us using mostly cherry and maple. If you install "storage" you can get away with much longer periods of time without any fire once the storage tank is up to temp.

 

[Coach B]

my main concerns are not having to baby sit it. i would like to be able to load it 1 or 2 times a day maybe less if that is at all possible, it should be atleast 80% efficient, and no smoke too annoy my neighbors

I have a regular OWB(Hardy) and they smoke like crazy. There is a reason I call mine a smoke dragon and a tree eater. However, I can get by loading it only once a day for a good bit of the burning season and twice a day during the real cold weather. They are very popular in my area.

 

[maplewood]

12 months ago I got rid of my old "regular" wood boiler, and installed a new gasification boiler.
I haven't seen a major decrease in wood consumption, but have seen a huge improvement in heat supply, heat recover time and overall operation.
I start more fires now, in the new boiler, but it is because I'm not smoldering a big fire and clogging up my chimney. Now I'm starting smaller fires, and letting them burn out, and re-starting a fire as needed. (I think I'll soon add a timer to my fan circuit so it only blows for 3-6 hours, and then stops, to save a coal bed for the next fire.)
Man, can this gasser ever make heat when it's in the "mode"!
Happy burning.

 

[mesuno]

Get some heat storage on your system ASAP!

If not you are wasting lots of the heat and the benefits of the efficient gasification in the first place. They work best run in short batches of intense heat which is stored and released back to the home when needed. Storage doesn't need to be expensive - we've been looking at options that involve little more than insulation boards, plywood and heavy duty plastic sheeting. Maybe $500 for parts if you do it yourself.

 

[willworkforwood]

Get some heat storage on your system ASAP!

If not you are wasting lots of the heat and the benefits of the efficient gasification in the first place. They work best run in short batches of intense heat which is stored and released back to the home when needed. Storage doesn't need to be expensive - we've been looking at options that involve little more than insulation boards, plywood and heavy duty plastic sheeting. Maybe $500 for parts if you do it yourself.

I don't take issue that having storage is better than running without it - most of us who frequent the Boiler Room are fully on-board about the benefits of thermal storage. However, running without storage does not automatically result in lots of lost efficiency. A boiler without storage can be very efficient, provided a few guidelines are followed. If someone is nearly always around to tend the boiler (as in our case), and the fires are kept small, the thing will run very efficiently with almost constant gassification. We run our boiler during the waking hours very much like a wood stove - a few small splits at a time. The boiler is in the basement, along with a month or so of wood, so frequent loading is effortless (however all of the work getting the wood there is a different story %-P ). Coupled with that are periods of time when the boiler is shut down - with full Sun that can be most of the day. During the nighttime burn, yes there will be some idling. But as long as the boiler is not greatly oversized, that typically isn't a big penalty. I agree that for the OP (who wants to load just a couple of times a day), running without storage would be a very poor choice. I believe the biggest benefit from having storage for most folks is personal convenience - eliminating what I described above. But if your lifestyle circumstances fit, then running without storage can be made to work very well.

 

[jerseykat1]

So without storage what would be a typical reload time on a 20 degree day on a 100k btu unit? And by storage i am assuming you mean a large hot water tank?

 

[willworkforwood]

Thermal storage is typically 800-1000 gallons, housed in one or two tanks. Some folks run with smaller "buffer" tanks, but that doesn't give the same benefit as the large volume. Although it's possible to fully load a gassifier running without storage and get an 8-10 hour burn, this will not result in anywhere close to 80% efficiency. With the heat load that your 1500 SF probably is, even the smallest gassifier would likely idle much of the time. Idling in a gassifier is lost efficiency, and frequently results in internal issues due to creosote buildup (commonly in the boiler HX). I'll throw out a round number of 10K as the minimum you need to get a quality gassifier up and running. Less might be possible, but not by much. Higher than 10K is more likely. So, you need to balance that with your current heating/DHW costs, and project it out over time. And the other big factor is cost of your wood - if you're buying c/s/d, a gasser would probably never pay for itself. There is lots of info in the Boiler Room - just search on keywords. You can probably find the answer to almost any other questions you have in the archived threads.

 

[jerseykat1]

i think i am leaning toward a regular wood burning furnace. I really cant justify the cost of a gasifier. i am only having a problem heating 3 rooms because there are off to the side on the farthest most narrow end of my home. The insert that i have in the living room heats the other half of my house just fine. The smaller units tend to be more efficient from what i have seen when it comes to standard wood furnace. would be an easy install since the basement is under the rooms that need the extra heat.

Thank you guys for your help.