LIVE image

What to like and what not to like about pellet stoves and pellet boilers.

Our Quadrafire pellet stove, which we can operate even during a power outage. Click to enlarge.
Photo Credit: Alex Wilson

We have a sort-of love-hate relationship with our pellet stove. My wife leans more toward the latter, while I see the benefits outweighing the negatives. In this column I’ll outline the primary advantages and disadvantages of pellet heating.

Advantages of wood pellet heating

Regional fuel. The fuel is—or can be—local or regional in origin. At a minimum it’s not fuel that’s coming from places where they don’t like us—like the Middle East. When I’m buying pellets, the source is a significant consideration. I’m willing to pay slightly more to have my pellets come from nearby plants in Jaffrey, New Hampshire or Rutland, Vermont.

Carbon-neutral. The life-cycle of wood pellet production and use can—and should—be close to carbon-neutral. With natural gas, propane, or heating oil we’re taking carbon that was sequestered underground millions of years ago and releasing that as a greenhouse gas into the atmosphere (where it contributes to global warming). When we burn wood pellets we’re still releasing about the same amount of stored carbon into the atmosphere, but that carbon was sequestered in the wood fiber over just a few decades, and if we’re managing our woodlands properly (replacing harvested trees with new ones) the entire life cycle results in almost no net carbon emissions.

Relatively clean-burning. Wood pellets are a lot cleaner-burning than cordwood. This is because pellet combustion is aided by a fan that supplies a steady stream of air to the burn pot. When I first start up my pellet stove—as the electric heating element heats up the pellets to start the combustion—there’s some smoke produced, but once the pellet stove is operating there is no visible smoke being generated. (This is a reason to set the temperature differential on the control relatively high—so that it won’t cycle on and off too frequently.)

Infrequent stoking. Pellet stoves have integral bins that can be filled every few days in cold weather, and most pellet boilers have stand-alone bins that hold several months’ worth of pellets. Regular stoking isn’t required—unlike with a wood stove. If a pellet stove is your only heating system in a space (as is the case with our apartment) how long you can go away depends on the energy efficiency of the building, expected outdoor temperatures, the volume of pellets your stove or bin holds, and the thermostat settings. With our pellet stove, we can go away for about three days in the coldest Vermont weather as long as I leave the thermostat set fairly low.

Convenient. With a pellet stove you don’t have to handle firewood. I’m sure I’ve cut, split, stacked, and burned a couple hundred cords of wood over the decades, and I know that it’s a lot of work. With pellet stoves you’re still handling the fuel—usually 40-pound bags of the rabbit-food-size pellets—but it’s more convenient than dealing with firewood.

Economical. Pellets are less expensive than heating oil, propane, or electric-resistance heat, so you can save money if you would otherwise use those fuels. You may save more money with a pellet stove by heating only a few rooms instead of the whole house—though there are often ways to do that with other heating system as well.

Disadvantages of wood pellet heating

Noisy. There’s no getting around the fact that pellet stoves are noisy. There are typically two fans: one to supply combustion air to the burn pot and another to circulate heated air into the room. I find the noise annoying; my wife hates it. It’s certainly a far cry from a silent wood stove in our living room. There’s a Wiseway Pellet Stove that supposedly operates passively, but haven’t seen one in operation yet. Pellet boilers are noisy too, but they’re typically in the basement or a separate building, so it’s not a problem.

Electricity dependent. When you lose power a pellet stove or pellet boiler can’t operate (unless you have one of those new Wiseway stoves). This is an important consideration not only in rural areas prone to power failures, but also more generally in an age of global climate change with more intense storms forecast. With our own Quadrafire Mt. Vernon AE pellet stove, I bought a kit that allow me to operate the DC fans using a 12-volt automotive-type battery during a power outage. It won’t auto-start using the DC power, so you have to start it by hand with kindling or starter paste, but at least it can be used to keep a space warm when the grid is down.

Comfort. Pellet stoves don’t deliver radiant heat. I love pulling up a chair in front of our wood stove on a cold winter night and sitting down with a good book. That radiant heat seems to warm you inside and out. Pellet stoves—at least the one we have—don’t heat up in the same way and radiate heat. Nearly all the heat is delivered by fan-forced convection. It’s just not as pleasant.

Plastic bags. Unless you get pellets delivered in bulk you produce a lot of polyethylene plastic waste from the bags. The first two years we had our pellet stove I was able to buy bulk pellets that were delivered in reusable thousand-pound totes that sat on pallets. I had to carry the pellets upstairs in five-gallon pails, but at least I didn’t generate all that waste. Unfortunately, the company that had delivered those totes disappeared, and I had to switch to the more typical 40-pound plastic bags (which we reuse as trash bags). I believe that as pellet heating becomes more common, bulk delivery of pellets will become more available.

Complex. Unlike wood stoves, pellet stoves have moving parts that can wear out and that require maintenance. There are blowers, temperature sensors, an auger to deliver pellets, and other components. Most retailers recommend annual servicing, which can add significantly to the total operating cost of a pellet stove or pellet boiler.

Less control over the fuel. If you have a woodlot you can cut and split your own firewood. That’s not the case with pellets. Pellet factories use massive presses to extrude wood fibers through dies to create the pellets. Do-it-yourself pellets aren’t an option.

Not always cheaper. While pellets are less expensive than most other fuels, they may not be cheaper that natural gas or air-source mini-split heat pumps. Use our Heating Fuel Cost Calculator to compare costs per unit of delivered heat. In the Northeast, pellets typically track with heating oil—going up when heating oil prices spike, though generally remaining significantly lower. If you can order pellets in bulk rather than buying them in 40-pound bags, there may be some savings—but not all that much. And there have occasionally been shortages of pellets, driving prices up substantially.

Bottom line

Pellets are a mixed-bag, but they offer enough advantages in many situations to warrant consideration. They provide a user-friendly option for relying on a relatively local, renewable fuel source. If Europe is any indication, the use of pellet heat in the U.S. is likely to increase significantly in the years and decades ahead.

Check out the high-performing, low-emitting pellet stoves that we've found in our GreenSpec section.

Alex is founder of BuildingGreen, Inc. and executive editor of Environmental Building News. He also recently created the Resilient Design Institute. To keep up with Alex’s latest articles and musings, you can sign up for his Twitter feed.

If you enjoyed this article, sign up for BuildingGreen email updates:

*

Comments

1 Your unflagging commitment to posted by Rhaud Macdonald on 05/18/2011 at 09:52 pm

Your unflagging commitment to the realization of 'appropriate building techniques/systems' should be lauded by all that build and design. It is unfortunate that the majority of movers and shakers in the building discipline tend toward the "scientifically" oriented mode of approach, justifying enormous outputs of energy for the manufacturing and maintenance of so-called modern and yet sadly destructive modes of construction, and internal environmental controls. The renaissance of the sixties and seventies pioneers, although with many assumptions and errors, was an enormous leap in the vision for a more holistic approach to residential and commercial structures continuing to the present day. However it is unfortunate that much like the priests of ancient Egypt who did all they could to ensure their position by controlling most aspects of learning - including engineering; our present day 'priests' have realized that the inquiry and innovations of the grassroots innovators has threatened their position in the proffesional hierarchy resulting in the many 'professionally' sanctioned programs that now threaten to damage our environment in much more subtle ways that sadly will result in more toxic and destructive consequences both for our planet and all of its life forms, including we humans. These programs they have so clearly 'BRANDED' that include such as the words as; 'sustainable' and 'green', are just simply that - BRANDINGS of self-interest groups which have sadly influenced many unwitting and un-inquiring, yet well-intentioned professionals and concerned lay people. Please keep up your good work. Thanx from an experimenter in design and construction since the late 60's, retired Building Technologies Instructor. Rhaud - LTDI, RDD, ADConsultant, Designer/Builder .

2 1. Requiring an engineer’s st posted by dave green on 05/19/2011 at 12:49 pm

1. Requiring an engineer’s stamp has nothing do with making it “all-but-impossible” to build one’s own home.

2. Since we aren’t eating our buildings (lead-loving kids and the Pica-diagnosed aside) what does it matter if the building blocks we choose to use are not as healthy as the fruits and vegetables at the local farmer’s market? What determines the “healthiness” of those foods? Who determines the “healthiness” of building products? Certified Organic is far from a measurement of how “healthy” something is. Locally grown food can be significantly less nutrient-dense and less healthy than food from other regions. This is an illogical position.

3. Deforestation occurred long before the industrial revolution – it was one of the principle warfare tactics of the Roman Empire in Northern Europe. Speaking of the Romans – many of the ancient buildings we know today were originally made of wood, and then torn down shortly thereafter for a larger, more durable version.

4. Autochthonous is not a Greek word.

5. By your definition, concrete is one of the greenest materials around. Concrete is so durable, there are concrete constructs dotting the Italian and French countryside that are over a thousand years old.

6. Exponentially growing populations can’t be sheltered in massive straw complexes – it’s just not feasible. The reality of the world is the majority of folks live in urban settings. Straw is a horrible building component for any kind of meaningful density. Engineered wood allows for the construction of 6+ story wood buildings that can solve those issues- are you a proponent of these intelligent and less-wasteful approaches to construction? If not, do you think your antiquated beliefs can actually help the majority of people that need housing now? Those beliefs no longer hold the relevant answers. Even the ancient Greeks built homes that were “less flexible and reslient.”

7. We definitely need to shift the paradigm, but calling the movers and shakers mere makeup artists does little to affect change. We’ve a long way to go, and not a lot of time to get there. Dropping everything for the myopic distopia you desire isn’t going to work. Working with folks, instead of offending those you disagree with, will be a much faster route towards affecting change.

8. Man has been creating monuments to myopia for millennia, why should he stop now?

3 Paula, First, and most import posted by Robert Riversong on 05/20/2011 at 07:30 pm

Paula,

First, and most importantly, I don't believe that Dave Green and I have the same goals. Dave has shared nothing about who he is or what he does or what his goals are. But I get the strong impression that he believes it is sufficient to lightly green up the current paradigm (which is fundamentally the position of the entire "green" building sector), while I am attempting to shift us into another, more authentically sustainable and truly green paradigm.

Secondly, whether straw bales or engineered lumber are "scalable for an exponentially growing population" is asking the wrong question, which is why it doesn't deserve an answer.

The best population ecologists have estimated that we surpassed a sustainable global human population of about 1 billion in the early 1800s and ecological footprint measurements indicate that the human footprint alone (ignoring the land base needs of the millions of other species) surpassed the earth's carrying capacity in the mid 1980s.

The ecological footprint today of national populations is double the human "fair share" of about 0.425 hectares/person (if we are to share this earth with other creatures) even in the poorest countries of Africa and Asia-Pacific. The per capita footprint of the "developed" nations is beyond redemption.

There is a law of nature just as inviolable as the Second Law of Thermodynamics: no problem created by technology can be solved by technology. And yet the alternative energy and "green" building movements are based on that fallacy. I invite you to read my latest essay "The Thermodynamics of an Intelligent Living Universe" and "What Does Green Really Mean?" at:http://transitionvermont.ning.com/profiles/blog/list?user=3tzma0zlrumce

Ultimately, Gaia will take care of the human overpopulation problem, but not before we set back the evolutionary process of life by 50 million years. The most responsible thing we can do at this present moment is to live as simply as we possibly can, use the most natural materials and methods to meet our authentic needs, and live with as much integrity as we can find within our deeply injured souls.

4 Since Robert and Dave seem to posted by Paula Melton on 05/20/2011 at 07:19 am

Since Robert and Dave seem to have the same overall goal, maybe we can get past the basic philosophical differences and disagreements about which words about the mystery of Easter Island and which words are Greek here and just answer some people's questions.

Robert, I'm curious whether you'll address Dave's comments about the scalability of straw bale. I didn't get the sense he thought there was anything inherently wrong with it, only that it was "not feasible" for "exponentially growing populations." You also didn't yet answer his related question about engineered wood as a more scalable alternative.

Dave, I would like to hear whether you consider concrete a sustainable material--by your own definition, not Robert's. And what would that definition be? I think perhaps even by Robert's definition (it outlives the time required for the earth to recover from its impacts), some concrete for some uses could be considered sustainable. On the other hand, how we measure that is a very tricky business.

5 Rhaud, I'm glad that another posted by Robert Riversong on 05/19/2011 at 01:54 pm

Rhaud,

I'm glad that another old inquirer and innovator is able to see the forest for the trees. Your comment about the "present day priests" of "green" building feeling threatened by anything which challenges the current dogma is quite evident in the comment by Dave Green, which could hardly be more defensive of the status quo and old paradigm thinking.

Rather than consider the content of my essay, Green's responses indicate that he did not comprehend any of my points, or he could hardly think that I consider concrete sustainable (though in some limited uses it can be) or that I would propose straw for urban high-rises. And, if he doesn't understand that for many people a requirement to employ an architect, a structural engineer and a soils engineer, as well as a licensed plumber, electrician and HVAC contractor makes housing unaffordable, then he doesn't appreciate the economic predicament of the majority of Americans (such as Devon Dougall, who responded to my first essay).

The etymology of autochthonous is more assuredly Greek: Autochthonous: literally, "native to the soil"; from autochthon +? -ous. Autochthon: from ancient Greek for ‘indigenous’ + ‘earth'.

But Green's concluding statement - "Man has been creating monuments to myopia for millennia, why should he stop now?" - says it all. The Easter Islanders drove themselves to extinction by focusing their energy on monuments at the expense of their ecology. We are on track to do the same unless we radically shift the human cultural paradigm to an earth-friendly subsistence.

6 Mr. Riversong, The content of posted by dave green on 05/19/2011 at 02:46 pm

Mr. Riversong,

The content of your essay was impossible to comprehend due to your incorrect understanding of history. It was your very definition of durable that pointed to concrete as one of the most sustainable building materials. If you don’t believe it to be, then your definition is incorrect. I wasn’t even discussing straw for high-rises, it’s a horrible material for low-rise or even multi-family housing of any meaningful density.

So now it’s plumbers, electricians, architects, civil engineers, etc. in cahoots to make housing unaffordable? You stated that the housing was unaffordable due to requiring a structural engineer to stamp drawings - a minimal, intelligent and worthwhile expense. Was it only when I pointed out the ridiculousness of your statement that it was expanded to the rest of the building trade?

Autochthon is of Greek origin, though I never contended that. You incorrectly stated autochthonous was a Greek word - it isn’t.

Several thousand inhabitants currently reside on Easter Island, so they (Easter Islanders) didn’t “drive themselves to distinction”. The erection of the Moai may or may not have led to the eventual decline of the original inhabitants of Easter Island, the remotest inhabited island in the world. The ecology of the island was so frail, a tsunami or severe hurricane could have had a similar effect. It’s not really an accurate representation of the resiliency of Mother Earth. And if they hadn’t built the Moai, we may never even know they had existed, which would be an even greater tragedy.

7 I was answering you only indi posted by Robert Riversong on 05/19/2011 at 04:04 pm

I was answering you only indirectly, since it was clear that you were not interested in a constructive dialogue – merely in the wholesale dismissal of ideas which you found challenging and hence "offensive".

But since you persist in your non-constructive retorts, it is necessary to respond for the sake of other readers who come with at least partially open minds.

Clearly, my essay was not so incomprehensible that a retired Building Technologies Instructor (first comment above) could not appreciate its message.

My definition of durable was quite plain: any material or structure which outlives the time required for the earth to recover from its impacts. Since concrete is the second most used substance on earth (after water) and, with its extraordinarily high embodied energy, is a major contributor to global warming (and mercury and particulate and noise pollution), and since a growing consensus of the world's climate scientists suggests that it will take the earth a million years to recover to an almost certainly higher temperature equilibrium than we now enjoy and 20 to 50 million years to recover from the anthropogenic great extinction that global warming (and our other depredations) is causing – by that definition concrete, at least used at current rates, cannot in any way be considered durable let alone sustainable or healthy.

If you believe that straw bales are a "horrible material" for residential construction, then not only are you apparently unfamiliar with its long history in the US for that purpose, but also with the current acceptance of straw bale building in a number of municipal and state codes (Arizona, Nevada, California, Washington, Oregon, Maine, Colorado, and Florida) as well as the new International Green Construction Code. And you can't possible be aware of the thriving straw bale building sector in both the southwest and the northeast, with examples in at least 32 states.

It's not only engineers, but all the over-valued building professionals as well as the increasingly complex prescriptive codes that those professionals create, on top of the escalating and artificial value of land, the inflating value of building materials, and the unnecessary sophistication of what passes for shelter today – all these together conspire to make housing unaffordable to the average working American. Materials and methods that allow more owner-build involvement, on the other hand, are among the few possibilities for increasing housing accessibility. I've been working with that disenfranchised sector for more than 30 years.

If you, indeed, had a deeper (or even superficial) understanding of the ecological history of the human race (not the textbook history which began with the great civilizations after 99% of the human story had passed), then you wouldn't be so misled about the Easter Island tragedy and its profound lesson for modern humanity. But you're quite right in your misquoting of me that the Polynesian inhabitants of Easter Island did, in fact, “drive themselves to distinction (sic)”.

"Against great odds the islanders had painstakingly constructed, over many centuries, one of the most advanced societies of its type in the world. For a thousand years they sustained a way of life in accordance with an elaborate set of social and religious customs that enabled them not only to survive but to flourish. It was in many ways a triumph of human ingenuity and an apparent victory over a difficult environment. But in the end the increasing numbers and cultural ambitions of the islanders proved too great for the limited resources available to them. When the environment was ruined by the pressure, the society very quickly collapsed with it, leading to a state of near barbarism." – A New Green History of the World, by Clive Ponting.

That researcher earlier notes "The population continued to decline and conditions on the island worsened; in 1877 the Peruvians removed and enslaved all but 110 old people and children. Eventually the island was taken over by Chile and turned into a giant ranch for 40,000 sheep run by a British company, with the few remaining inhabitants confined to one village."

Add comment

Login or register to post comments

— Share This Posting!

About the Authors

 

Recent Discussions

posted by atwilson
on Aug 19, 2015

Cynthia, yes that's correct; there is...

posted by cynthia.crawford
on Aug 19, 2015

Alex-Sorry- I meant to say sprayed- fiberglass. Thank you for your answer in any case, for both foam and fiberglass. It's the first time I've...

posted by atwilson
on Aug 18, 2015

Cynthia, Spider is a spray-fiberglass product, not a spray-foam, but neither material could be considered rodent-proof. In our home, rodent entry...

Recent Comments


Getting to Know Spider Insulation

Alex Wilson says, "Cynthia, yes that's correct; there is formaldehyde in mineral wool (urea-extended phenol formaldehyde). I'm not as worried about that as many others..." More...

Cynthia Crawford says, "

Alex-Sorry- I meant to say sprayed- fiberglass. Thank you for your answer in any case, for both foam and fiberglass. It's the first time I've...

" More...

Alex Wilson says, "Cynthia, Spider is a spray-fiberglass product, not a spray-foam, but neither material could be considered rodent-proof. In our home, rodent entry at..." More...

Cynthia Crawford says, "Since sprayed foam doesn't require boric acid, how does it prevent rodents from entering a building or burrowing into the fiberglass? They certainly..." More...


7 Tips to Get More from Mini-Split Heat Pumps in Colder Climates

Wendy L'Ecuyer says, "1. We've had a few assessments for a mini split installation in a master bedroom/ensuite. Some have recommended a 9000 BTU unit, the others a 12000..." More...