Hello, I'm new to the forum. I have a 1500 installed for two heating seasons now and absolutely love it.  We have a 1970s built somewhat efficient 2000sf raised ranch and easily get 24 hour of heat from a 2-3 hour burn and sometimes up to 48 hours between burns. Our heatload is low, averaging 15kbtu/hr during normal temps(30F) up to a max recorded 50kbtu/hr at single digit temps. (I've kept a spreadsheet of 2 years of data with burn-rate, temp, runtime, etc). Our neighbors (all woodburners) can't believe how little wood we use compared to their woodstoves.

Our town is now looking to ban all new wood boilers mostly due to a couple very visible 'outhouse' wood-smokers of archiac 'load n smolder' design.   Of course the building officials and town council know nothing about gassfiers, or burn-n-store, and are just responding to the perception of all boilers must be banned.

 Where can I find emissions and efficiency testing reports?  Are there any presentation materials available from Dectra or distributors for use in town meetings or to distribute to our building officials?  Thanks!

This is a fantastic question!  Let me try to give you a fantastic answer.

There has been a rise in small communities looking at banning wood burning as a way of combating the problems of "dirty burners".  The problems are very real, and in most cases, do need to be addressed.  The question is how to deal with the problem and not throw out viable, economic, and environmentally freindly alternatives.

"Dirty burners" have sold well for some 30 years due to the low initial cost in manufacturing poorly designed units.  As wood burning has become more popular to combat rising heating costs, it's become more and more clear to most people that these are very inefficient, of poor quality, and use a large amount of wood, most of which ends up in the air as particulate emissions.

There are, however, high-quality, efficient, clean-burning alternatives that do not cause the same problems, and do in-fact provide some great benefits.

There are several reasons not to ban wood heating:

1. Economic - Most heating systems use imported non-renewable fuels.  The money spent on these fuels leaves the community, and often the USA.  Individuals who supply cord wood are generally local so the money stays within the community, supporting the local economy.  Additionally, wood is often a more economical choice for heating which can reduce the local cost of living.
2. Environmental - Wood is a carbon neutral fuel.  The amount of carbon released when burning wood is the same amount absorbed by the tree during its growth.  Proper wood burning does not contribute to global warming.  In fact, burning wood is better for the environment than allowing it to decompose.  Decomposition is the same chemical process as burning, just slower.  However decomposition also produces methane (one of the worst greenhouse gasses), but is consumed as fuel when properly burned.
   Fossil fuels are not environmentally friendly, and even less so when you look at the total emissions used in the production and transportation of the fuel.  As an example, ocean going tankers used in the transportation of fuel oil to the U.S. are the 7^th largest source of emissions in the world!
3. Social - Local independence and sustainability contribute highly to community identity, and local energy independence provides additional incentive for people to be active locally both economically and environmentally.

There are a number of ways to address the problems of "dirty burners" without losing the benefits of using wood for heating:

1. Nuisance Laws - Often the impetus to look at banning wood is from nuisances.  This can be anything from creating a safety hazard by having thick smoke on a road or highway, to having it blow into the neighbor's yard and home.  Often existing nuisance laws can be used or expanded to address the issues.  These are typically complaint driven, but are highly enforceable. 
2. Emission Regulation - This is the best long-term solution.  It can be overwhelming for a small community to consider how to regulate or enforce emissions on wood units, but there are resources that are being developed to address this.
   About 5 years ago the US EPA (Environmental Protection Agency), ASTM (American Society of Testing and Materials) and HPBA (Hearth Barbeque and Patio Association) joined forces to look at this problem.  To date this coalition has:
   1. Developed a uniform test standard for all outdoor hydronic wood fired equipment.  This test will be conducted by certified independent test labs - not the manufacturer.
   2. Created two emission standards:
      1. Phase I, which went into effect in January 2008, is a voluntary program that limits particulate emission to .6 lbs per 1 million BTU input.  Considering some of the "dirty burners" tested in excess of 3.0 lbs per 1 million BTU input, it's a great start, but does not take into account overall efficiency.  GARN WHS units tested to .297 lbs per million BTU input (much cleaner than the standard) with an overall efficiency of 75.4%.  Other wood units tested to this limit so far range from 23% to about 50% efficient.
      2. Phase II, which will take effect in March 2010, will limit particulate emissions to .32 lbs per 1 million BTU output and take into account overall efficiency.  All units sold after March 2010 must meet this standard.  This later phase is to allow manufacturers time to develop cleaner, more efficient units that are able to meet the standard.
      The standards were developed nationally (in conjunction with Canada), but are adopted and enforced by each state.

The best and easiest approach to deal with "dirty burners" between now and 2010, is not to ban all wood burning units (including the clean and efficient ones available now), but to educate the community and potential buyers on the available technologies.  This, combined with complaint driven nuisance laws, can manage the problem in the short term.

Hope this helps.

 SwampYankee - this is something that every wood heat appliance manufacturer is going to have to provide pretty soon.  Central Boiler has made available a "model" zoning ordinance for use in public planning relating to outdoor wood burning furnaces.  I don't know if it has been used much or at all, but they are working hard to protect their interests.  I suspect that Dectra and other clean burning furnace/boiler manufacturers will have something to offer, hopefully soon.  

 The GARN has a Warnock-Hersey certification, but I do not believe it addresses emissions, just heat input and efficiency ratings.  I hope someone corrects me or expands on this if I am incorrect or incomplete.

 

My local township also just adopted (November 2008) an ordinance restricting the installation of outdoow wood heating appliances.  It basically uses setback distances as a means of restricting their installation to large parcels (at least 2 acres) and imposes some rediculous stack height requirements.  I was at the meeting where it was adopted, and I am grandfathered as my GARN was purchased before the ordinance took effect (I just have to register it).  However, I did query the board of supervisors about their knowledge regarding high efficiency gasification and secondary combustion type units like the GARN.  They were ignorant of their function, but the board was receptive to petitions by applicants that seek a variance from the zoning based on "new technology" that makes the operation of the wood burning furnaces "tolerable".  The low down is, the local officials are tired of complaints and dealing with whining residents.  Whether or not they have a valid claim, eliminating the "problem" through local zoning is easier than dealing with the issue.  Just my local political perspective.

 

By 2010, all units sold in the US will have to meet emissions standards.  The problem for most local communities is what to do in the meantime.

We do not have a "model" regulation or ordinance because things vary from state to state and region to region.  Instead we've been advocating either early adoption of the emission standards or the creation of a nuisance law.  Both would require the consumer to know what they were buying before getting it.

A nuisance law that resulted in a fine and/or shut down after some number of neighbor complaints would mean the buyer would need to look at emissions and talk with thier neighbors.  Early adoption of emission limits would require them to show that the unit is clean burning before installing it.

Some communities, like Jim's, adopt regulations to try to contain the problem using set-backs and stack height regulations.  These can be good at mitigating some of the problems, but they don't address the core issue of encouraging clean burning.  Stack Heights in particular are not at all effective.  You can read our article on stack height regulation on our resources page.

We've been advocating regulation for decades in order to keep the "dirty burners" from ruining the reputation of wood burning units, and to put a stop to the unregulated and outrageous claims of some of the less scrupulous manufacturers - including one who claimed their units were over 100% efficient!

WK, UL, and CSA listings are safety listings and not related to efficiency and emissions.  We strongly encourage all consumers to ask for independently verified test results.

Depending on your circumstances, your best resource might be to show your local officials your GARN unit in action.  There is nothing like a hands-on demonstration to show that clean burning is possible.

 

 Jim and Greg, 

 Thank you for your replies to this question!  I will prepare an information package to share with the building official and town council.  I would think the best way to deal with the complaints in the town is to focus them towards the problem units, not all of them. Honestly, I would be pretty upset if I lived next to a smoky system myself watching the owner throw in green wood and who knows what else in there. 

BTW, around here 2 acres is a small lot. The problem boilers in town are on 10 acre + lots. The planning board recommended the rule after repeated complaints on one particular horribly smoky boiler. They have a tall stack and meet reasonable setbacks, but still are stinking up the area. 

 Will Garn be tested to the EPA Tier 2 program? I thought I saw something that Dectra did not participate in the phase1 voluntary testing program because of the test procedure.. has this changed for phase 2?  

 Also, where would I find the results for the emissions test you mentioned above? I'd like to have that available for the building officials. 

Thanks!

GARN units will be tested in Tier 2.  The only reason we haven't been tested under the current EPA testing protocol is that the test cannot be done for units like ours.   The final ASTM test standard, which EPA will accept, includes procedures for testing units like the GARN units.  That should be approved in the next few months.

We do not anticipate any problem at all meeting the emissions numbers.  In fact the limits established for wood units were partially based on our results from the 2006 testing.  

 Let me know if you need anything else to help in your presentation.

 

 

 That is great news, Greg.  I look forward to seeing those results.  I also would bet a burger that Decta will be putting those new robotic welders into high gear once those data are published and promoted (hint hint) 

You mentioned testing done in 2006.  What testing was done? 

GARN IS NOT AN OUTDOOR WOOD BOILER Just because a GARN unit is a cylindrical steel tank does not mean it is filled with propane..... and just because it is often installed remotely from the space being heated...doesn't make it an outdoor wood boiler either. It has mistakenly been lumped together with outdoor wood burners because 20 years ago many outdoor wood boilers were cylindrical. And because GARN was a leader in designing heat/storage equipment to heat multiple buildings from a central energy center. If you look at many of these regulations they define an outdoor wood boiler as...... "Outdoor wood boiler. “Outdoor wood boiler” (also known as outdoor wood-fired hydronic heater, water stove or outdoor wood furnace) means a fuel burning device designed to (1) burn wood or other approved solid fuels; (2) that the manufacturer specifies for outdoor installation or installation in structures not normally occupied by humans (e.g., garages); and (3) heats building space and/or water via the distribution, typically through pipes, of a fluid heated in the device, typically water or a water/antifreeze mixture." or usually words to that effect. No. 2 is the key. GARN units are NOT specified by the manufacturer for outdoor installation. It is only specified to be 2 inches from any combustible. No where will you see that it MUST be installed "outdoors" or in "structures not normally occupied by humans". However, you may see it remote installation recommended to keep the mess of wood handling contained. Indeed many commercial installations have units installed in their working facility.... which until we go all robotic... is a space normally occupied by humans. GARN's unique design also separates it from your typical wood boiler, because it is a non-modulating heat storage device. That is why you haven't seen GARN on all the EPA lists. The only EPA standards for testing, focus on the cause of smoke and pollution, the modulation of the fire..... which GARN doesn't do. This is the whole purpose of the GARN design.... have a place to efficiently store the heat generated during combustion so it never has to operate in an inefficient and polluting manner. I heard someone refer to GARN's "simple" design as if any yokel could weld one up in his shop. You can find any number of down drafters, after burners, and other complicated designs that are trying to get the same results as a GARN unit with its two moving parts..... a motor and a hinge.... both easily obtained in any supply center. The sophistication of GARN's simplicity is built into its design. I think many people would be surprised at the amount of high-tech engineering that goes into the GARN design. You know an airplane propellor looks like a pretty simple thing to make too..... A GARN unit can be installed in any building as long as it meets its set-back requirements.... which happens to be 2 inches to any combustible at the top, sides or rear.

 This info is qouted from the back page of the Garn brochure. If it were me I would put it in bold faced print on the front.

 

"On January 29,2007 the US EPA issued Phase 1 emission guidleines for outdoor wood fired hydronic heaters (commonly known a outdoor wood fired boilers). The EPA phase 1 emission limit is .600 pounds of particulate emission per one million BTU input. Preliminary testing of a Garn WHS unit indicates an emission level of .297 pounds of particulate emissions per one million BTU input, 51% cleaner than EPA guidelines. In addition, overall efficiency was found to be 74.5% higher heating valvue basis (84% lower heating value basis)." ...... end of quote.

 

Further miscellaneous ramblings and observations.......

I am aware of the testing that Greg made reference to regarding OWB's and can say that I have  heard from a person I know in the Michigan DEQ/air quality division, that the efficiency numbers ranged from 28-41% for those type units. Dismal to say the least. There are some downdraft, gasifying type boilers on the market that will hit the same range or even a bit better than a Garn but that is only under steady load conditions (constant fire). Actual efficiency drops off when those units cycle to low fire or off (idle). The main key to the Garn's efficiency is the utterly simple principle that it operates under and that is , burn all the wood load in a single continuous burn. Such a burn is only possible with adequate heat storage capability. This, the Garn has in spades. On the european style downdraft gasifiers (EKO, Tarm, Econoburn etc. ) storage has to be added and many of the manufacturers of those type products strongly recommend the addition of a minimum of 500 gallons. I can say from experience with those types of boilers that storage is mandatory. I would not install one without at minimum of at least 800 gallons to "hold the heat" from the boiler. Anything less will not get you through a full burn on even the smallest models which fire at 80-100,000 BTU's. The Garn's ability to store heat as an integral part of the unit's design is unique in the wood/bio-mass industry as far as I know and there is no other princple of operation that works as well for a wood fired system. 

I was doing some reading on European websites for Viessmann and Froling (very high end/high tech wood boilers) and discovered that in Europe, a person burning wood must incorporate heat storage in the system in order to qualify for energy credits in the European Union. They take efficiency very seriously over there and that previously stated fact should tell all of us just how important BTU storage is to the overall function of any wood burner.

My own field testing has shown that a Garn will typically run in the 78-83% efficiency range depnding on the amount of fuel load and moisture content of the wood. (Measured with a Testo combustion analyzer). Flue outlet temps typically run in the 250-340* (not the Garn thermometer) range depending on fuel and where the load is in the burn cycle. By comparison, I have measured exhaust gas temps on many OWB's that exceed 1,000*F at full fire. Measured efficiency on those units (and I won't name names here) was below 40%. It doesn't take a rocket scientist to realize that if you are expelling exhaust temps in that range you are wasting a substantial amount of heat, not to mention the additional effort in handling all that extra wood.  

 Greg,

 

Thanks for the useful info.  My community has been enforcing burn bans lately due to pressure from the EPA on the recently enacted PM 2.5 standards.  However, they are still permitting the use of pellet stoves during bans.

Do you have any comparative data between Garn emissions and pellet stoves that I could present to my City enforcement folks?  And will the 2010 standards overlap with the PM 2.5 standards in any way? 

Thanks!

 In one recent trial of gasification technology gasification boiler operation has been put on a sound thermodynamic footing by the development work now completed. It has also been shown that, apart from its deleterious impact on thermal efficiency, the presence of water in mechanically-dewatered fuel (containing ~ 32 wt% solids) does not lead to significant particle disintegration compared with dried fuel. Gas trials have been staged using partial oxidation in three stages before final combustion. Nox emisssion rate was very well reduced from several thousand ppm to 25 ppm. Gasification in this system takes place in a fluidized bed formed above the slag bath and constituted by the dried sewage sludge or waste materials, the solid fuel, the oxygen-containing gas and the gasification gas. The gas produced in the gasifier can be used for power generation or for this example, as a reducing gas for iron ore.

 

__________________________

Greentech are specialists in a range of Gasification Boilers Services
 

Any new word on how the Garn tests relative to phase 2?  I get confused when the numbers change based on million BTU input and then change to million BTU output. My state (RI) is developing regs which reference EPA phase 2 as being 0.32 pounds per million BTU output.  The regs also have wording to the effect of "in addition, within each of the burn rate categories as established in EPA test method 28, no individual test run shall exceed 18 grams per hour".  There is a separate bill being introduced that attempts to make emissions limits retroactive (along with ridiculous set back and stack height requirements).  So I need to know what sort of footing I'm on when I speak to my state and elected officials.

 I'll second the request on the Garn emissions #s for phase 2.  Our town passed an ordinance last winter requiring phase 2 for new installations. Our garn was in place before the ordinance but got concerned last week with RI H7064 discussing retroactively banning even a Garn.  Overall our local reg is quite fair but the proposed state bill definitely is not! I spoke with and wrote our house rep (as did many others) and this is his response: 

"Friends, Thank you for contacting me regarding bill 7064 on Outdoor Hydronic
Heaters.  I didn't attend the hearing on this bill yesterday.  The room was
packed.

However, today I spoke with the prime sponsor of the bill, Rep. Ray
Gallison.  He has no intention of hurting people who have already bought and
installed these heaters.  The bill is being held, and will be considerably
re-worked.

Rep. Gallison's purpose, which we can probably all support, is to protect
air quality.  We have all heard horror stories of the type of garbage some
people have put in these heaters.  So I wouldn't be surprised if a revised
version of the bill includes restrictions on what can be burned and perhaps
minimum heights for chimneys.  Then there may be restrictions on what type
of burners are acceptable for future installations.

Regards,"

 That said, When will the EPA Phase 2 numbers be published for the Garn?  I've understand we can beat the .32 lb/mbtu but not the 15/18 grams/hour due to its burn/store design. 

 btw the RI bill is being disussed over at hearth.com http://www.hearth.com/econtent/index.php/forums/viewthread/52096/

 Thanks!