OWB, gasification, etc. I am so confused!

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muncybob

muncybob

Minister of Fire
Apr 8, 2008
2,158
Near Williamsport, PA
OK, a real newbie here so please bear with me! Now that heating oil in our area of PA. has hit $3.50 and higher and I just spent almost as much for 125 gallons of oil as I used to spend in 6 months...I've decided a change is in order!
Our situation:
We have an old and small farm house of apprx. 3 (3 story including the attic, 7'2" ceilings)with a new 2 1 story addition(mainly a game room). The addition is well insulated but the old farm house is not and except for the replacement windows and blown in insulation in the attic floor it will never be insulated any better. Current heating system is located in the basement & is oil fired water baseboard. The basement of our house is relatively small and the ceilings are very low(less than 6' in some areas). We have a few acres of mixed wooded area and live in the middle of a large xmas tree farm of which there are many overgrown pines. My initial thought was an OWB thinking I could burn just about any wood I can get my hands on including the pine but it seems the more I research on the inernet the more options I find. The OWB appealed to me since any "mess" is outside and I don't have to deal with frequent trips down the basement since I'm just over 6' tall.

If you had our situation would you be leaning toward an OWB also? I understand they are not very efficient but I have ample supply of wood very close to the house, have a truck and chainsaw and really don't mind loading up the boiler twice a dayin the winter....Any insight from you much more experienced people will be greatly appreciated!
 
Welcome aboard!
Take your time to do the research. Every option has pro's and cons.

1)Do a heat load calculation
2)What's your REALISTIC wood quality/quantity for the payback period
 
You should have a good record of how much oil you burn per year? If you can get the btu value for the oil you burn and figure 80% efficiency you'll know how many BTU you need per season. i suspect some is for DHW production also?

Certainly spend money on insulation upgrades first regardless of HOW you heat this will be your best return on investment.

Then calculate how many cords of pine, or what ever you will need to equal that amount of heat. With an OWF figure 40- 45% efficiency. maybe 70- 75 for a gasification. It may be a lot more wood than you think :0 Also based on the VT fellow that burns 8-10 cords for his 1500 square feet.

Just be clear on what it takes to heat with wood.

hr
 
Welcome to the Boiler Room, muncybob.

Here's the deal:

Gasification = 1.) Little to no smoke; 2.) Higher initial cost; 3.) Much lower wood consumption over time; 4.) Need very dry wood
OWB = 1.) No way to burn smoke free; 2.) Somewhat lower initial cost; 3.) Much higher wood consumption over time; 4.) Can burn wood in just about any condition.

When considering wood usage, be sure to factor in your time/effort/wood availability over the life of the boilers, which we'll arbitrarily put at 20 years.

Also bear in mind that OWBs are starting to be banned in various parts of the country. If you decide to go that route, try to find out what the local attitude is towards smoky outdoor boilers, so you don't find yourself with a boiler that you can't use in a couple of years.
 
Also keep in mind there are alot of Outdoor Gasification Boilers coming out. I too am researching myself into complete confusion, as there are so many options out there, with more coming down the line. I talked to the owner of Woodmaster friday, and they are coming out with a gasifier this summer, that sounds as though it is basically an outdoor version of the EKO or Tarm. 60-100 gallons of water, downdraft gasifier, large firebox to hold more wood, and about the same price as the indoor gasifiers. I am very interested in this stove, as after talking to him on the phone, sounds like it will fit my needs perfectly. Now once I can see one in actions, and real numbers come out it might not live up to the hype. But there are alot of options coming :)

Chris
 
magnumhntr said:
Also keep in mind there are alot of Outdoor Gasification Boilers coming out. I too am researching myself into complete confusion, as there are so many options out there, with more coming down the line. I talked to the owner of Woodmaster friday, and they are coming out with a gasifier this summer, that sounds as though it is basically an outdoor version of the EKO or Tarm. 60-100 gallons of water, downdraft gasifier, large firebox to hold more wood, and about the same price as the indoor gasifiers. I am very interested in this stove, as after talking to him on the phone, sounds like it will fit my needs perfectly. Now once I can see one in actions, and real numbers come out it might not live up to the hype. But there are alot of options coming :)

Chris
Click to expand...

I'd be much more likely to give something like that an honest look if it was actually being produced by Eko or Tarm, but I'd never buy a new model car the first model year it comes out, and I'd never buy a gasifier from a company that made exclusively "old tech" boilers previously until enough years have passed for them to refine their design to a dependable setup. A warranty is great, but the best any warranty has ever done is replace what broke... it won't repay you for the interruption and hassle.
 
Point taken, but with that thought in mind ~ someone has to be the guinea pig, lol. I like cutting edge technology. I build my own computers, latest and greatest components. I've bought new model year Chevy trucks the last 2 body changes. I have my own side business, etc. Someone in this country was the first one to buy an EKO, Tarm, Adobe, etc. Maybe a little naive of me in my thinking, but in todays market, I don't think the established manufacturers like Central and Woodmaster would jeopardize their companies by releasing a defective product. I'm sure they may have their problems, but in my opinion there are no 'Perfect' stoves out there ~ just what works best for each individuals situation....

Bottom line, there are a ton of new and current design stoves out there. The future of burning wood is upon us. I cannot wait to be another one to give the gas man the 'bird' :)

Chris
 
I met with " the gas man " today" the cost to run a gas line to my new home will exceed $ 5000- just another way to justify buying thaty gasifier!
As much as I like condensing boilers- I guess i'll settle for a 87% oil back up boiler.
Can't wait to start burning
 
I've used an OWB which expired after about 15 years of operation, and now have the Tarm gasifier, which I hope will last at least as long. Although I too enjoy cutting and splitting wood, there is something to be said for not spending nearly as much time on that task as I did before, and using the time for other things of life. Also, if you ever have to pay for wood, you will wish you were using less.
 
Everyone else has given you good advice as far as the heat calculation, wood supply, etc., so I'll address the "keeping the mess outside" aspect. This thinking doesn't lock you into a OWB; you can get the same less-mess benefit from a Gasifier by putting it in an outbuilding, as I and a couple of others here have done. You still get all the efficiency of the gasifier, and the mess is outside. But, you never get something for nothing; initial costs will be higher, as now you have to get that hot water to the house and back. Then, if you don't already have a building, there will be that construction cost. And there's that trek to the boiler house when it's 0 F. Given everything, I'm happy with my decision, but that's me. I just wanted to put this out to you as a consideration/alternative.
 
magnumhntr said:
Point taken, but with that thought in mind ~ someone has to be the guinea pig, lol. I like cutting edge technology. I build my own computers, latest and greatest components. I've bought new model year Chevy trucks the last 2 body changes. I have my own side business, etc. Someone in this country was the first one to buy an EKO, Tarm, Adobe, etc. Maybe a little naive of me in my thinking, but in todays market, I don't think the established manufacturers like Central and Woodmaster would jeopardize their companies by releasing a defective product. I'm sure they may have their problems, but in my opinion there are no 'Perfect' stoves out there ~ just what works best for each individuals situation....

Bottom line, there are a ton of new and current design stoves out there. The future of burning wood is upon us. I cannot wait to be another one to give the gas man the 'bird' :)

Chris
Click to expand...

Well, the guys on this board who chose to be guinea pigs for Adobe are all waiting for their states' attys general to start prosecuting the manufacturer and anyone else they can nail. So it doesn't always work out when you invest in brand new designs. God bless those who do, 'cause sometimes they need it. Gassifying OWBs will be a great thing all around, for sure, but I get the impression that there's not a lot of margin for error in the design of these things, and sometimes they work great in the shop but can fail to do the job under actual battlefield conditions.
 
I know of another Mn OWF manufacturer that tried to "ground up" build a unit to compete with gasification boilers. Over a million dollars later I believe they bought all of the ones they sold back. It looks simple from the outside, but there is some serious engineering to getting it right.

hr
 
Many of the OWB manufacturers have unveiled?? cleaner burning stoves utilizing secondary combustion to clean up the nuisance smoke issue. Cleaning up the smoke may not lead to better thermal effieciency. I'd be on the side of caution, most OWB's still have a large water jacket & a fire chamber that will hold pretty near 1/2 a cord:)
 
As I see it, the primary problem with the OWB is the water jacket around the firebox. It is a fundamental design flaw in that it surrounds the firebox with "cool" water, preventing the fire from burning at a sufficiently high temperature to obtain reasonably complete combustion. The only remedy is to obtain greater separation between the firebox and the water to be heated so the fire can burn hotter, and then to employ new but available technology (gasification, for example) to obtain more than secondary burn efficiencies.

The gasification boilers have achieved this to the point of up to 98-99% combustion efficiency. A free-standing wood stove, with secondary burn, achieves 60-70% or so combustion efficiency. A water jacket OWB achieves, as I have read, only about 20-30% combustion efficiency.

It will be very interesting to see what the OWB manufacturers do to achieve higher efficiency which is different from current technologies/design. Major barriers probably include the mindset of the OWB crowd that you can throw any junk in the boiler and get heat. It certainly is possible to do that and obtain an efficient burns, but to continue with the mindset and obtain efficient burns will result in a boiler appliance far more expensive than current gasifiers, IMHO.
 
I have a gasifier located outdoors in a small shed. So I feel I am getting the best of both worlds. I get less smoke than a traditional OWB and I am burning less wood.

Someone on this thread I think was alluding to my wood consumption versus size of house. In the end, to heat my kit log home with 6 inch logs and old leaky windows (covered with plastic) it is going to be about 7 cords of wood total for the winter. That is heating about 1200 square feet of open floor plan and all my DHW. Considering I burned 3 cords in a woodstove with no DHW before I feel this is pretty good.

Good luck -

Pete
 
I certainly appreciate all the responses...and it just confirms my initial feelings that I have a lot to look at before next winter. Yes, my DHW is done by my oil boiler which provides my baseboard heat. The concept of the gasifier in a shed is interesting. Given my current layout I'm looking at whatever I decide to go with being almost 100' from my house.....is this a major problem? Do all gasifiers need storage tanks?

Rambling out to feed the boiler in freezing cold temps is not a big deal for me as I need to do the same to feed the horses twice each day so I guess I could just make it part of my daily routine...but I do appreciate the fact that a more efficient system reduces those trips. Cutting wood again is not a concern at this point and I could probably use the additional exercise, but less work is good too! I do want to approach this from a environmentally conscious point so even though I have no neighbors within a mile less smoke and pollutants into the air appeals to me. Initial cash layout to make this change is of course a concern but I know that in the long haul I'll be ahead no matter what I do.

Again, do appreciate the feedback and any links to independant testing of both types of boilers would be great! Isn't the internet a wonderful thing!!??
 
I'm running mine at the moment without storage. It's a little more work, but nothing close to hard. People routinely run 100' or more of underground piping between their boilers and houses. Most OWBs go at least that far. My boiler is in the barn, which is about 100 feet from my nat. gas boiler in the basement.

Poke around here and you should find most of the answers you're looking for. And if not, ask away. Heck, if you get bored, start some threads and get some discussion going. The rest of us all do.
 
muncybob said:
Rambling out to feed the boiler in freezing cold temps is not a big deal for me as I need to do the same to feed the horses twice each day so I guess I could just make it part of my daily routine...
Click to expand...

Well, I'm not the brightest tool here, but I can tell you that the first year I made trips to the boiler shed about every 20 minutes. Many a nights I cursed GreenWood, the money, the smoke smell, yada yada yada. I can obviously only speak for myself, but even with experiance with wood stoves - though years ago - I found a HUGE learning curve. Today, I am generally satisfied with my decision, despite the fact that the Company absolutly sucks. Though I have lots of ideas about modic ications, I think in the begining it is best to run everything by the book until you get at least a year under your belt.

If you seriously want to load twice a day - without storage - I think you will have to overload, which will lead to idle, which will lead to smoke, which when found coming from a device detached from the house will appear to observers to be just another smokey OWB
 
OK, now I am leaning toward a gassifier that will be enclosed in an insualted structure of some sort sitting apprx. 100' from the house. I guess I'm also convinced that storage is the way to go...so can I install the boiler at this location and put the storage in my basement? What would be the apprx. size of a 1,000 gallon storage tank be? The only entrance to the basement is not very wide or high. How heavy are these tanks empty and can they be placed on their side to gain access to the basement?
 
Yes, you can put the tank anywhere you can pipe to. The basement is a good choice, since any heat loss (inevitable) will go into living space. The commercial tanks are easily moved and located, but expensive. My concrete cistern tank measures about 5 feet high, 7 feet long and 4 feet wide. The commercial tanks are collapsible
 
muncybob said:
OK, now I am leaning toward a gassifier that will be enclosed in an insualted structure of some sort sitting apprx. 100' from the house. I guess I'm also convinced that storage is the way to go...so can I install the boiler at this location and put the storage in my basement?
Click to expand...

Yes.

muncybob said:
What would be the apprx. size of a 1,000 gallon storage tank be?
Click to expand...

1000 gallons is about 134 cubic feet. So a 4x4x8 block would be close. But you can get (or build) tanks in a variety of shapes and sizes.

muncybob said:
The only entrance to the basement is not very wide or high. How heavy are these tanks empty and can they be placed on their side to gain access to the basement?
Click to expand...

With that sort of situation, I'd either build the tank inside the basement, or get a flexible tank (like an STSS tank), since the flexible tanks can be maneuvered into almost any place.

Joe
 
I queried pbvermont, who built his own version of a flexible storage tank. He used three sheets of fiberglass reinforced panels and pond liner. The panels are 4'x8', overlapped 4" and I believe he pop riveted them in a double row. Approximately 7' diameter 4' high would yield about 1100 gallons. The main expense would be the heat exchangers if you use copper, I am thinking of going with pex? Anyway, that is one alternative to a pretty inexpensive hx. I am also looking at a used propane tank as I think a closed system might prove more satisfactory.

Anyway if you are interested you might want to contact pb and see what his experience has been so far with his tank.

Good luck, Rob
 
Just a note of caution about all the gasifiers that the former OWB companies are bringing to the market.

Many of the designs I have seen go against the engineering found on the European patterned boilers.

I see a lot of them with firebox sizes that are nearly the same as their OWB designs. I think that there will be problems with this due to the fact that you want to keep the air flow pattern tightly controlled in a gasification system. A smaller sized firebox may mean you fill it a little more often but that design has proven itself over decades of use. The wood is kept more tightly packed which serves to speed the gasification process and enhance efficiency and clean burning.

Another thing that I think many of them are doing is supplying a lot of excess air to the firebox which serves to reduce the perceived amount of smoke. The big boilers at the power plants are run much the same way (when EPA isn't looking) to reduce NOX emmisions.
An over supply of combustion air will bring efficiency way down and drive flue temps up on any boiler.

Lastly, I would be very cautious about buying a product that is not backed by a solid company with a history of building boilers that work. I have a feeling that a lot of OWB companies trying to make the transition will not be around in a few years. (Adobe comes to mind) If it looks way better than anything else on the market and it's less money to boot.........That should bring your radar up to full scan and raise a few red flags.
 
Had my Taylor 450 delivered yesterday and now have hot water and heat to the basement, working on install to heat exchnger right now. I live in Franklin county, PA and know of at least 5 people around me who have OWB and we all love them. Wood here is rather plentiful and with gypsy moth coming back we will have lots of dead oak real cheap. I am doing the install myself and put the unit within 30 feet of the house and figure I will have between 7 and 8 grand until done. I had baseboard heat to install. Smoke is not bad here as we all live a couple of hundred yards apart and the common sense use of good wood really cuts down on the smoke. I hope to cut my electric heat pump and propane stove bill in half and believe it will do this ver easily. If you are looking for a wood gasifier try the company in Harrisonville, PA in Fulton County. I believe tehy are alternate heat systems, I almost went with them, but I had to put the stove in the garage which defeated the purpose of wanting to keep the stove outside. Good luck and choose wisely.
 
Muncybob

Major consideration for gasifiers is pressure vessel or open to atmosphere...
pressure may outlive due to less oxygen in the water.
Non pressure, the storeage/buffer is much cheaper, as long as furnace is slightly
higher.

Make sure your unit of choice, comes with cleaning tools or available to buy and easy access to the exchanger.

Furnace/boiler controls, the electronics are important and variable speed blower is almost the most important
part of the machine. your choice should have these features.

buy stainless if you can afford it

thx
doug
 
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