Searching for a switchgrass pellet burner

[Thomas Anderson]

I've been trying to find a pellet stove that can reliably handle switchgrass pellets. Only a few specifically say they can, and there are mixed reviews out on the interwebs. Has anyone here burned switchgrass pellets or know of a good machine to handle them? Looks aren't very important and neither is the size. This is a supplemental unit, so there's no minimum sqft I need to heat with it.

 

[My Oslo heats my home]

How available is switchgrass that it could be used as a common pellet fuel? Can it be added to other mixtures and used in standard pellet stoves?

 

[midfielder]

There's a Google group "Grass Energy" hosted by Jock Gill who has connections to all of the folks active in the field, academics, people pelletizing, etc. It's been pretty quiet recently but they know which stoves handle the high ash and mineral content of grass pellets best (used to know myself but have forgotten - CRS). Look for "BERC Grass Energy Group on Google".

 

[Thomas Anderson]

Well I have 12 acres of switchgrass which I hope to be able to pelletize on-site. It is perennial and vigorous, so it's an endless resource. There's lots of fallow farmland in the Northeast, and some of it is being turned to switchgrass for producing pellets and briquettes. A local school district burns the briquettes to heat their high school and elementary school. Only a few stoves I've found specifically say they support switchgrass pellets. From the few testimonials I've read so far, it would seem that it puts out slightly less BTUs than wood pellets and burns cleaner than corn. I've been using loose switchgrass for years as a convenient fire-starter for my wood stove. It burns really hot and gets the logs going well, so I have no problem believing it would work great in a pellet stove. Once I can find an adequate stove, I'll buy a pellet mill and start producing my own pellets. From my understanding, the stove has to be able to have settings for feed rate and air mixture ideal for burning the different kinds of fuel. So I'm looking for one that has such flexibility and performs well with switchgrass.

 

[Thomas Anderson]

I'll have to dig into that. Thanks, midfielder.

 

[DexterDay]

Most true "Multi Fuel" stoves (stoves that have an agitator in the burn pot) can burn just about anything. The agaitator helps to stir the fuel and allow the ash to be ejected.

The main thing with burning something like that, is the quantity of ash and the production of the pellet...

You say you have 12 acres of Switchgrass. So I assume you will be pelletizing the product?

Some stoves with an agitator are the Enviro Maxx-M, Enviro Omega (discontinued), Magnum Countryside, Envrio M-55 Steel, Enviro M-55 Cast, Englander 10-CPM, Englander 10-CDV, Harman PC-45, Regency GS-60, Vistaflame VF-55 and 160, and a bunch of others (Breckwell had 1 or 2?). But most anything with the stir rod will burn the dirtiest of dirtys.

Welcome to the Forums.

 

[imacman]

As Dexter mentions above, most multi-fuel units should handle it, with an edge going to ones (like my Englander 10-cpm) that have settings for different fuels, and/or have fuel feed/air feed adjustability. Myself, Jay T, and Schoondog burned grass pellets (goldenrod), grass/wood, and even coffee pellets without much difficulty....heat was good, BUT......

IMO, unless you have PLENTY of time on your hands, or can get the fuel VERY cheap, the grass-types fuels are a LOT of work. Ash levels are very high, and the stove had to be cleaned 2-3 days....even w/ a big ash pan.

 

[schoondog]

As Dexter and Imac have mentioned a multi fuel stove is a must. I have a US Stove that is an inexpensive multi fueler and a stove I would recomend for your experiment. Burning grass is alot of work and we haven't even spoke about pelletizing. Hope your not to busy. But I thought it was kinda satisfying to do. I found the best way to burn was mixing with wood pellets, made good heat and stretched out your stash of good pellets, yet satisfying because you ar heating your home with a very renewable resource.
There was a company that was advertising a mobile pellet press that would come to your property and pellitize your grass.. They were in Highland or NewPaltz NY. They were supposed to send/give me a bag of grass pellets but never hooked up. I think the name was Murphy.
Good luck !

Schoondog

 

[Thomas Anderson]

I'm not too concerned about ash. I currently use a wood stove (which I often start with a handful of switchgrass) and clean it out every few days during the heating season, so I don't see much of a difference there. I expect the pellet stove will need less tending than a traditional wood stove. I'll be producing the switchgrass pellets myself, so it will be essentially free (amortized cost of pellet mill plus diesel to run it) and I will be allowing the grass to overwinter until late January in order to reduce moisture content which should make it burn pretty clean.

I have been thinking that the Magnum Baby Countryside might be a good one to try. It seems well-built, specifically mentions that it is tested with switchgrass, fits nicely in the space I have available in my 2nd floor living room, and has the option to run on 12VDC, which I have wired throughout my house attached to my house batteries (so no inverter failures). Does anyone have any experience/opinions on the Baby Countryside?

 

[imacman]

I'm not too concerned about ash. I currently use a wood stove (which I often start with a handful of switchgrass) and clean it out every few days during the heating season, so I don't see much of a difference there.....

Many people on this forum are wood burners or are ex-wood burners (including myself in the latter group). Believe me, cleaning out a wood stove is NOTHING like a pellet stove.

IMO, try burning pellets ( a ton or so) for a while before trying the grass......you might change your mind after that.

 

[papa bears stove]

I have burned switch grass in my Paromax Europa and it handles it very well. You can contact Claude at Paromax for more information if you would like as the Paromax stove utilize gasification as well.

 

[DexterDay]

The Baby Countryside has LOTS of Airflow problems from the factory. Leaky ash pan gasket, hopper gasket, air wash is to large, to many holes in burn pot, etc. Which all lead to a terrible burn. Even with some mods done to it (plug some of the air wash, fix gaskets, plug holes in pot) its still gonna "Choke" on the High Ash content of Switchgrass. My Best friend 1 mile down the road has one and it had to be mod'd just to burn a premium pellet (Somerset) and it could still use a stir once a day. Without the mods, it had to be tended to about every 8 hours (stir and pull some ash out of pot with a spoon).

The Counryside is an actual Multi Fuel burner.. The Baby is not. The Baby was designed as a Clinker Corn Stove (low air flow and clinker must be emptied twice a day). The Countryside has a stir rod designed to chew through the toughest of fuel.

In my opinion, if your stuck in Magnum (AES) then go Big. Or I am afraid you will be disappointed in the results.

Oh and lowering the moisture content of the grass will help, but its still going to be MUCH higher ash percentage than premium pellets (less than 1%). Your gonna be looking at several % of ash (or more) which equates to a lot of cleaning. I burn wood too and as imacman said above, there two totally different animals. Burning grass is gonna take a lot of work.

Do you know the average BTU's of a pound of Switchgrass? Wood pellets are generally around 8,000 BTU per pound. With the grass producing less BTU, your gonna have to feed a higher rate, to get the same heat. So choosing a larger stove seems to make sense (to me). The Baby is under 40,000 (closer to 30,000 IIRC).

Lots of good stuff your thinking about. Love the independence...

 

[midfielder]

Have you looked at reed canary grass as well? Its ash content's supposed to be lower than switch, especially if you let it leach.

 

[Thomas Anderson]

My grass is an already established resource, so it would not make sense to destroy it and plant something else. I don't know yet what the BTUs or ash percent will be. That'll require testing and experimenting. From what I've read online, the BTUs should less than wood but more than corn. The ash level should be somewhere in between too, but again, until I try it I won't know for sure. I don't mind checking on (refill/empty ash) a pellet stove every 8 hours. That's a longer interval than a wood stove needs stoking. When you say it is much different, I'm not getting your meaning.

 

[Delta-T]

your investment in a unit to burn grass will be the easy part...processing the grass will be the challenge. There's a couple of commercial size grass burners in PA that have their own stock and equipment, but that equipment is HUGE. Enviro makes some cool multi fuel units that should have no problems with grass, and I'd bet that Harman's PC45 would do just fine as well. No matter what, you'll be doing some tinkering. The grass process is still fairly young and has a lot of variables that the stoves are not necessarily designed to deal with....yet. Expect clinkers, expect more clinkers if you run the unit really hot. I met a few guys from Syracuse that were working on a portable harvester, pelletizer for grass, though I haven't herd much about it in a few years. Would be neat if you can pull it off...I wish you luck.

 

[SmokeyTheBear]

Welcome to the forum Thomas.

papa bear's stove is unique in the business in several respects and is ideal for burning a wide range of pelletized or small grained bio-fuels. It uses an ash extraction system that augers away the accumulating ash in its burn pot. It also operates on a much lower airflow rate than the other stoves do and has a very large heat exchanger to harvest a large fraction of the heat for distribution into your house.

Whatever you do make certain you put the proper multi fuel venting on the stove as what you are planning on burning isn't always nice in the corrosive byproduct side of the fire.

 

[jtakeman]

Welcome Thomas,

IMHO, I would stick to a stove that cleans itself in one way or another with grass pellets. Grass pellet produce some where around 3 to 5% ash. I haven't seen a clinker type stove(the baby) handle them all that well. The exception is the bottom feed Harman, But you still need to tend to them at least a couple of times a day. You will need to keep the air holes clear/clean in the burnpot. This is where the stirrer/self cleaners make life simpler as they do the tending for you. You'll still need to clean them a couple times a week(or when the ash pan is full), But at least you won't have your head it the stove several times a day.

Timothy grass and Canary grass, May have slightly less ash. But it depends on when it was harvested. AFAIK, they all do the best when rented in the field which reduces the silica content. IMHO the switch grass is slightly higher overall. Aprox 14.4 Mil BTU's/ton(7200 BTU/LBS). I have seen postings of 8100 BTU/LBS. But like wood pellets as the moisture content rises the BTU content is reduce. BTU content also depends on compression. Home grown pellet mills do have the compression of a Industrial mill. Just some FYI.

 

[ohbix]

Bixby stoves should be able to burn switchgrass. I read a study, I think by a NY Univ, in which they tested switchgrass pellets in stoves. The Bixby performed very well.

 

[FyreBug]

We test on switch grass and bark pellets. We manufacture the following units will handle it no problem and do not require an agitator. We certify them to run on switch grass.

• PSG Caddy Alterna Pellet Furnace
• Enerzone Euromax
• Enerzone Eurostar
• Osburn 5000

Papa Bear has used some of these and can comment on them. Let me know if you have any questions.

 

[jtakeman]

We test on switch grass and bark pellets. We manufacture the following units will handle it no problem and do not require an agitator. We certify them to run on switch grass.

• PSG Caddy Alterna Pellet Furnace
• Enerzone Euromax
• Enerzone Eurostar
• Osburn 5000

Papa Bear has used some of these and can comment on them. Let me know if you have any questions.

Nice to see a stove that is certified to burn grass! I have heard some stove dealers warning people not to burn grass pellet as it will void the warranty. Brands begin with a Q and an H. Specific stoves are the Mt V and the PC-45.

How often did you need to scrape the burn-pot while burning grass? I have heard the bottom feeders still need some tending while the stirrer stoves do not.

 

[papa bears stove]

Hey Fyrebug how are you? Indeed I have burned many fuels in the Euromax, Eurostar and the Alterna furnace. All have burned whatever I've put in them without any issues or problems. I once burned cherry pits in the Alterna to the point where ash was half way up the glass and it was still running well. *Note that the manual does not list cherry pits as a approved fuel. I just had to try it!!

 

[papa bears stove]

Welcome to the forum Thomas.

papa bear's stove is unique in the business in several respects and is ideal for burning a wide range of palletized or small grained bio-fuels. It uses an ash extraction system that augers away the accumulating ash in its burn pot. It also operates on a much lower airflow rate than the other stoves do and has a very large heat exchanger to harvest a large fraction of the heat for distribution into your house.

Whatever you do make certain you put the proper multi fuel venting on the stove as what you are planning on burning isn't always nice in the corrosive byproduct side of the fire.

Great info Smokey!! Good to know you are familiar with the Europa. I will note that in my memory bank in case I am in need of assistance.

 

[FyreBug]

Nice to see a stove that is certified to burn grass! I have heard some stove dealers warning people not to burn grass pellet as it will void the warranty. Brands begin with a Q and an H. Specific stoves are the Mt V and the PC-45.

How often did you need to scrape the burn-pot while burning grass? I have heard the bottom feeders still need some tending while the stirrer stoves do not.

I did not see it personally burn it switch grass. But the engineers seem to think its not the greatest fuels for all the reasons you guys mention. However, our torture test is to burn it so it overflows the ash pan & the burn pot until the ashes are over half way across the glass (about 3 or 4" above the pot itself). The units dont burp or fault.

 

[papa bears stove]

The switch grass I have used is betweem 5-7% ash content The ash is white in color when it is burned correctly and is real fine ash. Definitely lower in BTUs than wood pellets. The switch grass I have used has came from Cornell University (not sure where they got it from) and from Enviro pellet in Unadilla NY.