Use of USA Forests for Home Heating - Can this Sensibly be Expanded?

This is one of my favorite posts by Nate, from back in 2007. I often think about it when people talk about how a large amount of wood can be used to create cellulosic ethanol for our cars. Nate mentions in this article that we are already using virtually all of the wood growth increment each year for home heating and other uses. Wood is not really a very expandable resource, without the USA becoming like Easter Island in not very long.- Gail

A short fifty years ago, people heated their homes in winter with coal. A hundred years ago and before, people living in cold climates largely stayed warm in winter with firewood. Today, in a country (and planet) with vastly more people, we heat homes in northern climates largely with high quality fossil fuels, specifically natural gas, heating oil, and propane. Trees, a less energy-dense form of stored sunlight than oil and gas, have recovered a good part of their former % of landcover in the US, despite being still used for paper, wood, furniture, pulp and some heat. Below is an analysis of how the US residential sector heats its homes, how large are our forests and how much they grow and how much wood we could use for heat, after fossil fuels decline.

US direct fossil fuel use for heating Click to enlarge.


Peak oil and Peak Natural Gas have so many implications that I could think of a new one (and write about it) pretty much daily. In a recent discussion of the depletion of high quality fossil fuels with a neighbor - she quipped "Well - I guess its time to buy a woodstove then". It was the same day that the EIA heating oil inventories had dropped sharply. This got me to thinking, which resulted in the below analysis of how much heat from fossil sources we currently use and how much could be generated from our forests.

At some point in the next decade, perhaps later, probably sooner, we will likely be faced with liquid fuels shortages. Coincident with the decline in high quality oil production, a portfolio of alternative energy sources will be sought out to fill the gaps, both on the macro scale and by individuals. Already given increases in heating oil and natural gas prices, there is renewed interest in using alternatives to fossil fuels. Consumer switching ability for home heating exists, as it did in the 1970’s, but in today’s world we have little choice but to go southwards on the energy pyramid (oil/NG to wood or coal) as opposed to the lateral movement 25 years ago (oil to NG and propane) (Natural gas has more hydrogen atoms than does oil, and both have more than wood).

What if some of the TOD and private forecasts for dramatically higher oil and gas prices occur in the coming years? People quickly respond to these price signals, and may increasingly look to heat their homes using more traditional means that they can individually control. Trees are ubiquitous, and it takes but some money or effort to create a nice neat stack of warmth producing wood next to ones home, especially for the more rural dwellings in our nation. Living in Vermont and buying firewood for my woodstove has made me ponder the following questions: What if everyone wanted/needed to heat with trees at the same time? Would there be enough trees to go around? What is the annual biomass ‘interest’ vs. existing forest ‘capital’? Could any states replace their winter heating requirements sustainably from forests? (note: the Drupal spell check is telling me 'sustainably' is not a word...;) What would be the environmental impact of over-harvesting for heat? Would home heating demand for wood then displace other wood uses, (electricity, lumber, paper, etc.)

(A special thank you to long time oildrum contributor and GIS whiz, Luis a de Sousa, for helping create the GIS images of the United States).


The US uses over 7 quadrillion BTUs (quads - written 7,000,000,000,000,000) for heating our homes each winter (out of 100 quads total energy use). Heating needs are a function of a) cold temperatures, b) population and c) efficiency of heating method (I suppose I could add d)tolerance/preference). As seen in the below graphic, natural gas is by far and away our largest source of residential home heat, followed by heating oil and propane, which is a product of both natural gas and crude oil refining.

2004-2005 United States residential heating BTUs, in quadrillion units (quads) Click to enlarge. Source: EIA and Propane Council.


Some notes on the data. Heating oil is the combined total of distillate #1, distillate #2 and kerosene, though the vast majority is distillate #2. Home heating use of distillate fuel (essentially diesel) is about 10% of total distillate use. (highway trucking is over 50%) (Source). I used 2004-2005 heating data partially because it was easier to find but also because the last 2 winters were among the lowest in the last 30 years as far as fuel usage. 2001 and 2003 were considerably higher (11% and 13%). 2004-2005 was close to the average of the last 7 years. There are a small number of homes that still heat directly with coal but good data doesn't exist so coal was excluded from the analysis. I don't particularly trust the EIA data on wood either as it appears they use the amount of firewood purchased and reported so those numbers may be light because of do-it-yourselfers are not good at reporting-it-to-authorities. Also excluded were heat generating sources/devices like the sun, better insulation, extra blankets or dogs, cats and spouses. In the broadest sense, these are very real heat sources, but they should still be there after fossil fuels decline.

Electricity makes up a minor part of home heating use - of course, there is also natural gas and coal used as a precursors to electricity but I didn't extend this analysis that far. (About half of all energy used by a household goes to heat and cool the home. (116 billion kWh (2001) = 116 billion * 3,413 Btu = 396 trillion BTUs (.396 quads))

US residential heating is dominated by natural gas - more than 2/3 of our home heating is derived from piped natural gas. Below is a historical graph of demand for this largest component of heat in the United States.

Historical United States usage of natural gas for home heating, in quadrillion units (quads) Click to enlarge. Source: Energy Information Agency.

Current county by county United States usage of propane for home heating, dark blue >25%, light blue 10-25%, tan <10% Click to enlarge. Source: US Propane Council.

In 2005, 18.895 billion gallons of propane were sold in the U.S. 7.942 billion gallons were sold to residential users. At 92000 BTU per gallon this equated to about 6% of our residential heat needs. The above graphic illustrates that propane (LPG) is primarily used out West, and in the more rural areas that may not have natural gas pipelines or consistent oil access.

United States natural gas and heating oil use in millions of BTUs per person .

Heating demand is essentially a function of population and cold (temperatures). The above graphic shows the intensity of fossil BTU use for home heat per person.

The northeast and midwest have the coldest temperatures (and or the wimpiest people). Maine uses the most heat per person in the United States, but their low population makes the state itself not one of the higher ranked users. Adding the population factor produces the below graphic:

United States natural gas and heating oil use per state in trillions of BTUs.


Humans have used wood since the dawn of civilization and historical scarcities of wood have triggered major technological changes. Wood shortages in Greece taught architects how to exploit solar energy. Thousands of years later, shortages of wood forced England into the fossil fuel era, and it began a widespread use of coal. Englands attraction to America was in no small part due to the scarcity of timber resources in the British empire and the awareness of huge wood resources in the New World. In the United States, the market for coal expanded slowly and it was not until 1885 that a low population density, heavily forested nation burned more coal than wood. Even in the world today over 2 billion people use firewood as their primary fuel source. (1)

United States forest statistics compared to the World - Source National Forest Service (2).

United States land and forest statistics - Source National Forest Service (2).

The US was heavily forested when it was discovered/populated in the 1600s. (note that the 30% decline in last 375 years is by land area not by volume of wood). Though the statistics above mask it, in the 1800s so much wood was used for construction, export and heat that the eastern forests were largely clearcut. Vermont went from 100% down to 40% forest cover and has since rebounded dramatically. According to biologist Stuart L. Pimm the extent of forest cover in the Eastern United States reached its lowest point in 1872 with about 48 per cent compared to the amount of forest cover in 1620. In the last 100 years, the amount of forest, due largely to presidential decree of increasing reserve land and intensive tree planting has generally held steady or increased.

Rates of growing stock growth, removals, and mortality on productive unreserved forest, 1953-2002. Source: USDA Forest Service (Graphic first posted on TOD by Stuart Staniford here).

The US standing forest as of 2002 was 856,000 million cubic feet. The annual growth of this forest is 23,689 million cubic feet, or around 2.5% of the volume. The above graph shows historical trends of growth, removals and mortality on non-reserved forest - the growth on this type of timber is closer to 3% annually. As can be seen, the forest size was gradually growing as annual growth outpaced removals and mortality until recent years. Now the annual growth net of mortality is just about used. There is no rule saying removals cant be above growth - that just portends a smaller forest the following year. (It is unclear how much of the dead wood can or could be used, and decaying woods impact on soil nutrients and ecosystems is beyond the scope of this post.)

Total US forest products for all uses 2002 - Includes Hardwood and Softwood - Total wood used 15.7 billion cubic feet Click to enlarge. Source (2) National Forest Service.

Less than 10% of our wood use currently goes towards fuel use, and even less of this towards heating. The forest service did not break down this category into fuelwood for home heating and other fuel sources, though one can assume the majority is for residential use (though I know my schools city, Burlington, VT uses wood to generate heat and electricity for the public utility). The total use of 15.7 billion cubic feet is less than the annual total growth of 23.69 billion cf, but there is mortality of 6.3 billion cf which needs to be subtracted (though in theory this would have some heat value). Essentially, we are using all of our forests growth right now, even at the same time we are using all time record amounts of coal, oil and near record amounts of natural gas.

Cords per wood (128 cubic feet) per person in individual states. Click to enlarge. Source (2) National Forest Service.



In 2002, the forested area of the United States contained 856,000,000,000 cubic feet of tree volume, of which 364,000,000,000 cf were hardwoods. (This is the forest capital). (Due to larger amounts of creosote and much lower wood fiber density in softwoods, they are not suitable for conventional firewood and I assumed are not used for heating –in a more advanced analysis this assumption could be relaxed as people could harvest softwoods and replant with hardwoods at least to some extent and/or install external wood burners).

The current annual volume growth is 10.1 billion cubic feet annually (or about 2.5%). Existing usage rate is 5.7 billion cubic feet with an annual mortality rate of 2.7 billion cubic feet. (Interestingly, the mortality rate was at a 50 year high and the USFS admit they do not know the reason for it). For ease of calculation let’s be aggressive and assume that humans can access all of the dead wood for burning. We then have 4.4 bcf of annual growth of potential firewood that is not otherwise being utilized for lumber, electricity or current home heating. At 128 cubic feet per cord, this equates to approximately 34.7 million (more) cords of wood that can be accessed sustainably, without dipping into the forest ‘capital’. If we discontinue other current market uses for the wood we would have 10.1 billion cf or 78.9 million cords of potential firewood per year.


Each cubic foot of natural gas, depending on its origin, has about 1,027 BTU’s. #2 Heating oil has 149,793 BTU’s per gallon. Kerosene, used in some places for winter heating, produces 134,779 BTUs per gallon. In total, the amount of fossil fuels used for winter heat in the United States equates to over 7,000 Trillion BTU’s. (2001/2, a much colder winter, was 13% higher).


Freshly cut wood has over 60% moisture and therefore takes much more effort to release the energy in the wood fibers. Seasoned wood approaches 20% moisture content and releases about 6,400 BTUs per pound of wood. (Pure bone-dry wood tops 8,000 BTUs per pound but is not practical for home use). Almost all wood types create the same amount of BTUs per pound (6,400), but depending on their individual densities and other properties, differ in how many pounds make up 1 cord. Some examples are:

Hickory => 4,327 lbs per cord => 27.7 million BTUs per cord
Red Maple => 2,924 lbs per cord => 18.7 million BTUs per cord
Cottonwood => 2,108 lbs per cord => 13.5 million BTUs per cord
Cedar => 1,913 lbs per cord => 12.2 million BTUs per cord

A complete list of wood types and BTU content per cord can be found here

This analysis assumes one cord of wood typically is about 2400 pounds. We then arrive at 2,400 X 6,400 BTUs =15,360,000 BTUs per cord. Therefore, in the 52 US states, we have 34.7 million cords of annual volume growth of wood available times 15.36 million BTUs per cord => 533 Trillion BTUs that can be presently be accessed sustainably from hardwoods. (If we eschew all other forest products, this number roughly doubles, and if we include softwoods, it roughly doubles again)


Heating with wood is not as efficient as heating with natural gas or #2 heating oil. A significant portion of the heat generated from burning escapes up the flue to dissipate as heat in the atmosphere. Wood stoves and furnaces average about 55% efficiency. This compares to 85% efficiency for natural gas furnaces and 80% for furnaces using #2 heating oil or kerosene. (the lower the efficiency rating the more BTUs of heat is ‘lost’ and unable to provide heat to targeted areas).

So, of the 5,030 trillion BTUs generated by natural gas furnaces in 2004, 85% or 4,275 trillion BTUs went directly to heating, and 15%, or 755 trillion BTUs was dissipated as waste heat. Similarly, of the 998 trillion BTUs generated by heating oil, roughly 80%, or 799 trillion BTUs went directly to heating.

Of the 532 Trillion BTUs that could be generated annually from forest growth, approximately 55% or 297 Trillion BTUs would end up as ‘actual heat’. Natural Gas and Heating Oils collectively generated 5,074 Trillion BTUs of ‘actual heat’. Thus, this analysis indicates that we could sustainably replace 297 / 5,074 Trillion BTUs or 5.8% of fossil fuel home heating use with home heating from wood. Alternatively, the entire United States forest stock of hardwoods contains 364 billion cubic feet of wood, or 2.84 billion cords which would throw off 24,024 Trillion BTUs (note, this is only 24% of the total annual energy usage of the country). So the good news is if we were really cold and sans fossil fuels, we could chop down trees for at least 4 years before the US would resemble Easter Island (24,024/5,074= 4.74 years). On a state by state basis, the distribution would look like the following:

Years of heat in standing forest (hardwood only) in individual states. Click to enlarge. Source (2) National Forest Service.
To see a graphic including softwoods click here


If there is wide scale deforestation, for heating, ethanol or other uses, we will increase the CO2 in the atmosphere directly through wood burning, and indirectly through loss of soil biomass, not to mention changing the water/irrigation patterns due to increased erosion, etc. Furthermore, there are already cities/communities with inversion problems that limit the amount of wood-stove burning on certain days due to particulate matter and air quality. An in-depth environmental assessment of over-harvesting the annual growth in wood biomass is beyond the scale of this preliminary analysis, but of course is both relevant and important.


This last statement suggests that only a moderate amount of switching can occur given macro constraints. Consumers however, do not look at the macro picture of sustainability, but at their own microeconomics. Let’s see how the current rates of $2.70 heating oil and $14 natural gas (retail) stack up to $260/cord.

Cost per Million Btu's (MBtu) Useful Heat Into the Room:

1) Fuel oil at $2.70 per gallon: There are 149,793 Btus per gallon of fuel oil and oil furnace efficiency equals 0.80:
1,000,000 Btu x $2.70/gal
149,793 Btu/gal x .80 = $22.84/MBtu

2) Natural gas retail at $14.00/1000 cu ft, 1007 Btu/cu ft, and efficiency equals 0.85:
1,000,000 Btu x $14.00/1000 cu ft
1,007 Btu/cu ft x .85 = $16.36/MBtu

3) Wood ( red oak) at $180/ cord, 19.6 MBtu/cord, and efficiency of airtight stove equals 0.55:
1,000,000 Btu x $260/cord
19,600,000 Btu/cord x .55 = $16.70 /MBtu

At today’s approximate prices, the per BTU cost is about equal natural gas and wood but a good deal less than heating oil. For those that own their own trees however, cutting them may prove a substantial savings. Economic theory would suggest that as fossil fuel prices increase, wood prices, as a substitute, will also increase – the large private landholders then may hold the key to whether we dip into the forest bank account when a fuel shortage presents itself.


1) Technically, since forests and people are not uniformly distributed, and a tree is too large to fit into a woodstove, energy must be used to reduce forests to manageable human chunks (by chainsaws or axes) and then transported to individual houses (by trucks or horses). These tasks mostly require oil. To an individual, the added costs will show up as higher price for cords of wood. To a society, they result in less BTUs available to heat what is needed from the new source. Clearly with NO fossil fuels, to obtain these amounts of BTUs from wood would be unattainable, as one would need chainsaw and transportation ability to cut all but the low hanging fruit in ones yard. So the net BTUS to the system, as opposed to each individual should be considered (in an Energy Returned /Energy Invested sense). Obviously, as with oil, there is a gross resource (which Ive presented here) and a net resource - I expect people in Colorado won't be heating their homes with the trees on Pikes Peak as they would likely be procured only at an energy loss.

1a)(deleted) I decided to make the discussion about wood harvesting, time and net energy a separate post - "The Energy Return on Time"

2)Using softwoods, while creating some problems, would increase the available BTUs available annually by 45% or so.

3)Very little of the Southern forests are used for winter heating. In this way, wood could be ‘imported’ if it were necessary. Again – how much would it cost to do this (in $ and energy?)

4)At some harvest point greater than the sustainable harvest of 5.8% of our heating requirements, there would arise externalities from loss of ecosystem services. Clearly the scale does not exist for large increases in the amount of firewood consumed annually without environmental consequences.

5)Walmart, Home Depot and others have recently been selling large quantities of electric heaters. If people are switching to electrical heat due to high fossil fuel prices, this will in turn increase the price of electricity and increase the amount of biomass currently used for electricity production (thereby reducing the amount of wood available for home heat)

6)Most population dense areas, and most new houses, don't easily have the ability to heat with wood. But external burners might be come popular in a hurry if winter heating needs increase in price or availability. In the same vein, most modern houses dont have the ability to NOT heat with natural gas unless modifications are made. This is another example of how fixed vs marginal energy investment will be key - like the automobile, home heating is not just a plug-and-play BTU problem, as there is long lead time necessary to change relevant built infrastructure.


This post has been a first look at the comparative scale of our home heating use from fossil fuels vs. more traditional methods. A more rigorous analysis using dynamic systems modeling could eventually be a component of a larger renewable energy meta-analysis.

We are at the very early stages of a Sustainability Revolution, equally momentous for humankind as were the Agricultural and Industrial Revolutions. While no one can know with certainty the timing of the decline in liquid fuels, analysis can be put in place ahead of time to focus our efforts on alternatives and portfolios thereof that collectively give us a chance at sustainability. While there is seemingly a huge inventory of trees in our country, there is also a huge inventory of humans and their respective consumptive wants. Warmth and protection from cold are among the most basic of our human needs – quite simply, there are not enough trees for an annual growth harvest to provide more than a fraction of our current heating needs. I don't really expect we will return to heating with wood, but the point of this exercise is to show that if the market should incentivize people to heat with wood, we have upper limits in expanding our use of wood for heating, and they are not too far from where we are now. This analysis provides yet another example of the power, density and importance of natural gas and oil in our society.

(1) A Forest Journey: The Story of Wood and Civilization, Perlin, Josh,; Countrymen Press 2005

(2) Forest Resources of the United States(large pdf warning), Smith, W. Brad; Miles, Patrick D.; Vissage, John S.; Pugh, Scott A. 2004 General Technical Report NC-241. St. Paul, MN: U.S. Dept. of Agriculture, Forest Service, North Central Research Station (I encourage anyone with an interest in trees and forests etc. to peruse this long pdf - lots of fascinating data)

Excellent analysis!
In the SW United States and Texas, the drought is killing off many hardwood trees, such as oaks, furnishing plenty of wood to burn. Many 400-hundred dead live oaks are evident across the Texas Hill Country due to a fungus and perhaps weakended by by long term drought. Mnay ranchers would welcome a market for there dead live oak trees.

I think most of the trees you mention are victims of oak wilt. The live oaks of the Texas Hill Country have lived through droughts in the past.

One of the features which helps them weather drought, interconnected root systems, has the unfortunate side effect of being an infection route for the oak wilt fungus.

When totally dry, sewage sludge has about 4000-7000 Btu/lb, which is equivalent in heat to lignite coal.

That last graphic, "Years of Heat in Standing Forest", tells the whole story. The SE US, upper New England, and the Pacific NW are the places were wood has the potential to carry a significant portion of the heating load. To my way of thinking, it does not make sense to transport firewood long distances (that requires a lot of energy, too), those places that are near the forests and need the heat are the places where wood heat is most feasible.

I suspect that if the data were availabile to break this state-by-state analysis down to a county-by-county analysis, what you would find is that it is particularly those counties in and immediately adjacent to the mountainous areas of the SE US, Upper New England, and the Pacific Northwest, that are particularly favorable for wood heating. It is in the mountains, of course, where the trees are, the land not being favorable for farming. Populations tend to be less dense in mountainous areas as well. I suspect that a few other areas would also be favorable on a county-by-county analysis: Central PA and Upstate NY, The Ozarks, parts of northern CA, parts of Southern IN & OH, and a few other places. There would also be places in the SE US, Upper New England, and the Pacific NW that would drop out, being too flat, unforested, and overpopulated.

Of course, population density is also an issue. In a small town like mine in the Southern Appalachians, surrounded by massive hardwood forests, it makes all the sense in the world for many people to be burning wood. If everyone in Atlanta would try to do that, though, I don't know if breating would still be possible.

yup -just like with most other issues, there are numerous local/regional solutions, but few macro solutions, other than reducing consumption.

Ironically if industrial production crashes, then there will be less demand and lower prices for natural gas so wood won't be needed right away. However, the lower prices will result in speeding up of the natural gas treadmill and result in higher prices in the not too distant future - higher prices that many will not be able to afford so wood will become a real option. The aspect of this analysis I left unaddressed is that of air pollution and inversion from a step-up in wood burning. That might be even more limiting than the strict BTUs, based on population. I know there are already restrictions in many US communities, that have plenty of wood.

The main difference between our present global oil culture and the renewable culture which we will likely move toward is the fact that renewable energy tends to be very local. By that I mean that each location will have it's own combination of available renewable energy sources. Different locations should thus pick the best alternative to match their particular set of options. Your comment about "macro solutions" misses this fact, IMHO. Similarly, trying to move wind generated electricity from the Northern Great Plains to the East Coast may also be a bad idea.

As you and WNC points out, using wood in traditional wood stoves to heat a major city would present a major pollution problem. Wood stoves are a step up in technology compared with a fireplace, but most aren't as efficient as possible. This situation has been seen in the West in mountainous areas, such as Missoula, MT, where stoves have been installed with catalytic converters on the exhaust to reduce noxious emissions.

Furthermore, you failed to mention the widely available wood pellet stoves, which can burn both soft wood and hardwood pellets. The technology to make the pellets is decades old and the machines are readily available for local production. If wood stoves were refined to use the best available technology, including condensing heat exchangers as found on high efficiency gas furnaces, I think the improvement would greatly increase the utility of the wood resource.

E. Swanson

by 'macro solution' I meant, as you did, one-size-fits-all solution.

This article is two years old -agreed re wood pellet stoves but that is not what people had at the time nor have right now (in large amounts). A version of this paper is being submitted for peer review with updated numbers from DOE and USFS - I had planned on linking to it when published.

Actually, I think that wood pellets might be more of a "macro solution".

My wood burning experience has shown me that firewood use is closely tied to the type of stove. By that I mean that one uses wood which is cut to fit the particular stove. I would cut my wood into 20" slices, whereas my friend would cut his to mo more than 17" length. My neighbor wants his cut to less than 13". In short, there is no uniform size for firewood, no "one size fits all" as with fossil fuels. with oil, we have a few very clearly defined types, be it gasoline or diesel for transport, #2 heating oil for homes, kerosene or propane. These fuel divisions have allowed common technologies to evolve into highly refined systems. With firewood, a similar single type would be that found with pellet stoves.

BTW, pellets can be made from many biomass sources such as switchgrass, not just wood. Thus, pellet stoves might represent the best solution for the "one size fits all" problem.

E. Swanson

By chance, I just heard a discussion two weeks ago of switchgrass pellets vs. wood pellets. Apparently switchgrass pellets have a dramatically higher ash (mineral) content, on the order of 10-20%, than wood (0.5-1%). Because of this, it's not advisable to use switchgrass pellets in stoves that are designed specifically for wood pellets, as they may "gum up the works" with the much higher ash load. So even in the pellet world, there are compatibility issues.

If wood stoves were refined to use the best available technology, including condensing heat exchangers as found on high efficiency gas furnaces, I think the improvement would greatly increase the utility of the wood resource.

It would be interesting to know also how much further wood usage could be extended if rocket mass heaters were encouraged or became more popular. They use less wood and burn it more efficiently. They're also relatively inexpensive to build. Theoretically, anyway - I haven't tried it - yet!


Rocket stoves are a type of masonry stove. That may be good technology to avoid the need for iron/steel and the machines that are used to construct metal stoves. And people who have masonry stoves seem to love them. But I cannot believe the efficiency claims for them. There are so many BTUs in a pound of (dry) wood, no way around that basic fact. The range of possible efficiencies is from 0 to 100%. Good iron stoves are up around 70%. The theoretical maximum can therefore only improve that by a factor of about 1.5. And I have no reason to assume the masonry stoves are anywhere near 100% efficient either.

Masonry stoves do have the characteristic of having a high heat-absorbing mass, which means that they keep warming the house for many hours (even days) after the fire is out. But that also means that it takes a long time to warm them up. And if the weather turns unexpectedly warmer after the stove is hot, then the heat (and wood) is wasted.

Of course we should be talking about what we can do and not what we have done. We have done a lot of messy, smelly, unsafe, polluting wood stoves. Why bother? We know how do very clean ones that put out nothing either visible or smellable. And, we can also put out wood/pellet/any combustion heating systems that also generate significant amounts of electricity along with their heat. After all, what is a wood stove except a burner without its engine attached?

That engine could be, among others, the same stirling engines used by NASA for long life space missions-- but optimized for low cost instead of super high efficiency and low mass.

I have been playing with this concept for too long (low budget) but now it is working and looks ready to mass produce. So- here we go- burn up the forests to make electricity to do --What? MakeMoreCrap!

Then I think of Rudolph Diesel, pacifist, and how his great idea became so popular-- as the prime mover- for U-boats!

Aye, there's the rub. Until we get our priorities right, nothing we do, no matter how clever, and no matter how clean, helps a bit.

I am thinking more and more often that the only real solution is a mass extinction -of us.

Maybe I'll feel better in the morning after my half cup of tea.

I have been heating with wood most of my life here in the SE. During the winter I also cook and heat water with wood. i use only hard wood and never use wood that has been seasoned less than two years. While my wood heater will heat most of my 2000 sq ft. home if i turn on the air handler from the central air to distribute the heat generally I just heat a 6oo sq ft room where everyone seems to congregate during chilly weather. The great advantage to a wood heater is that folks just seem to gravitate to the warm space around the heater, making it unnecessary to heat the entire house. Sleeping in a cold room is something everyone should get use too. I should note that it takes many years to learn to operate a wood heater correctly. I use a minimum of three thermometers at various places on stove and exhaust pipe to constantly monitor temps to insure efficient operation. Stove and pipe maintenance is critical. Wood stoves are extremely dangerous! While i have a wood lot on my small farm I get most of my wood from discarded wood from power line clearing operations and from neighbors who cut down damaged or unwanted trees.

Agreed. I heated all this winter completely with wood. I use a dab of kerosene for lamps and a small kerosene heater and that was a bit less than a 4 gal container of K-10...

I used zero electric or propane or N gas to heat with. Don't even have a method or applicances to heat with elec or gas of any type.

And I used somewhat less than a full cord. I went into winter with just a very small pile so I hauled and cut and split as the temperatures required it.

I stopped burning the wood heater a week ago. I never use it but about 7 hours a day at the most and rarely overnite.

I live alone but if my wife or any of my children were here they would definitely NOT be able to cope with what I described above. They would flee immediately!

As to the varieties of wood in the forests of Ky and most particularily Western Ky. I believe a huge amount of the stats are incorrect.

For a long time sawmills and pulp mills and also chip mills have been harvesting our timberlands with a vengeance. They literally strip the land. They 'take no hostages'. They don't care one bit what it looks like afterwards, nor do they REPLANT. Thats a laugh.

And for many years the hardwoods like Oak,Pecan, Walnut, Persimmon and Hickory have been decimated. There is basically none of pecan and walnut left. Then they came (Japanese) and took all the paulownia.

What is left that most people look at and oggle is just sweet gum and soft maple,some hard maple. They grow fast like weeds. They produce little heat.

Enough oak and hickory have been cut such that repopulating is not going to happen much IMO.
Besides these are slow growing trees. At least oak is. Hickory somewhat faster. Hickory can be a real bitch to split. Really tough.

Oak is good to split. White oak the best and red next. I used mostly downed oak and hickory this winter.

IMO here, and I think this holds true for much of the SE but not sure about the Smokies....we have far less good hardwoods than I believe is stated to exist.

Note new house construction. Do you see real plywood anymore as sheathing? No you see OSB...chipboard. Made by chipping wood of many types and glueing it together. Real good plywood is now rather expensive. This means we are using junk wood and other wood and in large quantities to build all the consturction.

At too dimension lumber? 2x4's and up...I see trash. Very poor grades. Lots of knots and gum pits and bark on them...The quality since what I used in my log house back in 1990 has rapidly diminished.

So my view is that when other heating sources are depelted or become too expensive that many will resort to stealing others wood. Out scavenging for dead limbs and such. Just at they do now in third world countries.

But here the populace his very heavily armed. At least more so in the lest populated areas. They will surely not stand idly by as scavengers raid their means of survival.

It will get very bad. Very bad. This report indicates to me that for this reason alone those ideas of Kunstlers about the revival of
the small villages is not going to happen. No fuel to cut,none to transport and therefore not going to survive.

Thanks for the report and essay. This is really where the buck stops at. Literally.

As others are prone to say....
Nuff Said?

As we watch all those petroleum resources dwindle and shut down we are dreaming about the future. Pure dreamstuff.


Excellent post Nate, one of the main concerns I see with peak fossil fuels is the rush towards biofuels making the problem of soil depletion & CC worse by removing carbon sinks and intensivly farming biofuels. I think a far better solution is to; move towards high insulation standards making use of solar gain,
Where homes are not on the gas grid make use of local wind resources and electrically driven heat pumps, I make it about 2.5 quads from non natural gas heating, using a COP of 2.5 for the heat pumps means we require 1 quad of electricity which is about 300,000 GWh according to

For wind turbines each MW of capacity will generate about 2.5GWh a year (0.285 capacity factor) which gives us 120GW of installed wind capacity, roughly 5 times the current capacity (~25GW) the US installed 8GW last year so allowing for 25% a year growth (quite high but the last few years have seen growth of around 20-50%) all non gas heating can be replaced with wind powered heat pumps in 7 years. Of course if you cut heating demand by 20 or 50% with passive solar techniques, insulation) this number reduces to less than 6 years or less than 4.

The roll out of wind turbines and heat pumps along side each other would also help overcome the variations in the output of a wind turbines allowing the electricity to be stored as useful heat inside buildings without any round trip losses from storing the electricity. With frequency response and other 'smart' control systems (most likely through some sort of internet or local radio connectivity) on heat pumps and electric battery charging, it should be possible to get lots of renewable energy sources onto a grid.

The roll out of wind turbines and heat pumps along side each other would also help overcome the variations in the output of a wind turbines allowing the electricity to be stored as useful heat inside buildings without any round trip losses from storing the electricity.

I doubt this would be very efficacious. The heat retention time for most residential buildings is less than 24hours, and the time needed to wait for the next weather system (if your wind farms are becalmed) is usually on the order of a few days. Of course heat retention time should increase linearly with insulation, thus another pro-insulation argument can be made. Of course if we had smart meters and supply-damand driven electricity rates, we could always use electric (hopefully via heat pumps), during high availability periods. Getting a significant portion of the population to accept significant thermal variabilty in their houses may be quite difficult. The TOD readership is quite unusual in this respect.

You say "I doubt this would be very efficacious. The heat retention time for most residential buildings is less than 24hours"

Well, there are easy ways around this. It's called a hot box. A phase change salt in a box with insulation. Very cheap stuff. Along the lines of a 'smarter' night store heater with insulation. One can store heat for over 5 days just with the insulation. You can store heat indefinitely with a seed crystal type setup. ie first heat is indefinite (heat output triggered by introduction of seed), then any more heat stored relies on insulation until the salt is melted to a super saturated solution again via the heat pump.

Certainly, the length of possible heat retention (basically as long as you want) is much longer than the 'becalmed wind turbine' period. Becalmed wind turbines are a bit of a joke just like bird deaths. Here in NZ they are turning 80-90% of the time.

Hi Kiwi 11,
"Becalmed wind turbines are a bit of a joke just like bird deaths. Here in NZ they are turning 80-90% of the time."

Wind turbines will be turning >90% of the time in any location used for wind power, however, they will be producing less than <30% capacity factor for most of the time, and only 5% of the time near maximum rated output. Just the same, periods of several days no wind do occur occasionally, and we need to have some form of back-up for those periods.

A country like NZ or Canada with lots of hydro can easily back-up and just turn down hydro during periods of high wind, with no loss of efficiency( unless dams are overflowing).

No form of generation produces electricity at its full output, 100% of the time, so a capacity factor of less that 100% does not mean a form of generation is unreliable.

Here in NZ the capacity factor for wind is 40-45%. The new farm going up at Makara will be over 45%. (No subsidies here... it's just smart business).

This is a little lower to capacity factors for other types of generation, but does this really matter - no. Our hydro runs at about 50% capacity factor but this varies depending on rainfall. In dry years in can drop quite a bit and then come the large advertising campaigns to reduce demand sufficiently otherwise face blackouts.

Other capacity factors are: gas is 63%, geothermal is 83%. Generators are often offline because of maintenance, unexpected faults, fluctuations in demand or constrained fuel supply. Not sure about the capacity factor for coal but I know that they've had their share of problems like when the Waikato River overheated in summer and they had to shut it down. Another time, they hadn't opened the coal seam in time and yeap in spite of all those million tonnes of coal sitting in the ground, they had to import a few barges from Indonesia... a couple of months wait there.

Diesel fuel oil capacity factor is the lowest as it is by far the most expensive form of generation. One can see current generation anytime is NZ at

But the system in the future will be moving towards managing demand rather than supply and the heat store mentioned above is one pretty simple way of doing it. Another simple example is a cold store created at night for refrigeration or air conditioning. This would use cheap electricity at night as well as the cooler night temperatures, so the heat pump doesn't have to pump so hard. (The Chinese are already doing this for some brands of air condtioners).

Backup is needed for any type of generation if security of supply is needed to be maintained at an adequate level.

Excess wind energy and electric thermal storage, or wind in combination with dual fuel heating systems (e.g., oil + electric) seem like a good fit, but you need to ensure all ratepayers are treated fairly. There has to be sufficient financial incentive for homeowners and/or utilities to invest in these types of systems and, at the same time, the benefits must be distributed among all customers more or less equally. That's a fine balancing act.


Technology and the market can go a long way to balance all of this as long as the opportunities are avaliable to the consumer.

I buy my residential power online at "The Power Shop"

I buy power from different utilites in any combination that I choose for now and the future depending on what I want to support (ie green power, cheap power, specials etc) and can compare prices or buy in bulk.

The next stage will be to install smart meters and buy power for time of use. Off peak power is so much cheaper ( see I've seen it at $0 and at $5000 MWhr) that that would be all the incentive I need to move anything I could to run at night or in the cheaper periods.

It's how we get from Point A to Point B that worries me. We're basically looking for some way to dump excess energy and there are a couple of things that haven't been properly addressed. For example, will these controllable loads be sufficient to absorb this surplus energy and can they be kept in relative balance as additional wind capacity is brought online? Will the price differential be sufficiently attractive to entice homeowners to invest in the required hardware and/or modifications to their current heating systems? What do we do with this excess energy during the off-seasons? What are the costs and logistical requirements in moving to a smart grid and real-time pricing (both required for this to work) and who's going to pay for it? Will all customer classes benefit or will one group of customers be unfairly advantaged over another?

Nova Scotia Power offers very attractive TOU rates to residential customers with ETS heating systems. After many years of active promotion, less than one per cent of residential customers have adopted this technology, most likely due to the significant upfront expense -- typically $6,000.00 to $10,000.00. You would think that anyone who heats with electricity would jump at the opportunity to purchase it at half price, but this hasn't been the case. Wishing doesn't always make it happen.


"What do we do with this excess energy during the off-seasons?"

- make fertilizer or aluminum. No reason to make those at a constant rate, as they store well...

Couldn't be that hard to combine the technology in a smart meter with a wireless ADSL router.

I thought a similar thing with a fridge/ freezer and heat pump? It would be a useful thing to dump excess electricity into.
Does anyone know if anything similar has been proposed?

Yeap, the Chinese make ice at night - insulate - for their air conditioners using the cool night air and off peak electricity. Very cheap, very easy simple technology. Refrigeration could be done likewise.

This brings up the huge issue of how transmission is operated and for whose benefit.

It took a heck of a lot of activism for some utilities to be forced to accept net metering, but that is really a very weak system. I know of no where in the US where you can charge the utility exactly what they are paying for energy at a particular moment for energy you produce.

The basic point is that a lot of changes that need to happen simply aren't going to unless a whole lot of people get active and organized and demand them to happen from their legislators and utilities.

Even when it is in the best long term interests of the utilities, overcoming entrenched attitudes about what is doable and worth doing takes a lot of organized work. Technical knowledge is great, but political knowledge is what those aware of energy issues, those on this forum, need in spades. And the first bit of knowledge is that it doesn't just happen by itself.

The only reason my local utility moved at all toward wind, even though it made economic sense long ago, was because activists took them to court. I think there is an assumption these days that if you just come up with a nice-sounding solution, it will get adopted. Or that mere cynicism toward the political process is an adequate or responsible or even acceptable position.

We need to keep learning all we can about what does and doesn't work, we need to keep asking deep questions about what energy is for, but we also have to start figuring out what the best way is to influence power, whether corporate, legislative or NGO, to move the conversation in sane directions.

Because there are plenty of powerful interests that will continue to do everything they can to continue the worst of the status quo.


Isn't this making the problem harder as the first step of trying to solve it?

The roll out of wind turbines and heat pumps along side each other would also help overcome the variations in the output of a wind turbines allowing the electricity to be stored as useful heat inside buildings without any round trip losses from storing the electricity.

Trying to solve the problem of volatility of a wind resource at the local level is making the problem far harder than it needs to be ... the output of multiple wind resources with multiple wind farms each are far more predictable than the output of a single wind farm, let alone a single wind turbine ... and pooling wind power withthe harvest of other volatile renewable energy sources reduces the system variability even further.

Pooling in a grid with long-haul import/export lines to other grids permits more effective use of dispatchable conventional hydropower.

Then the heating solution of a well insulated house that reduces its active heating load with effective use of passive solar design, supplemented by geothermal assist heat pump, reducing the height of the winter peak, is likely to be a more energy efficient design overall.

Modern woodstoves have efficiency of about 80%.

With a combination of superinsulation, heating only a portion of the house, smaller residences, use of passive solar elements where appropriate and so forth, it would not be very hard for the U.S.'s total home heating use (in btus) to fall by 80% over a period of three years or so. People just have to decide to do it. Over a longer period, allowing new construction specifically designed for low energy use, a 90% decline is entirely possible in my opinion. 90% is an additional 50% decline from 80%.

Nate's assumption of 55 % efficiency for wood stoves and furnaces seems to be far away from Central European standards. In Austria the following efficiency rates have to be met in order to receive a seal of quality from the Ministry for Environment (in German: )

- Automatically charged boilers and stoves (e.g. pellets, wood chips): 90 %
- Manually charged boilers and stoves (logwood): 80 %

No disagreement on what is possible, other than pointing out it costs money, energy and time to get from what we have now:

Conventional wood-burning appliances which are not certified as low emission average 50 per cent efficiency, with a range of 35 - 70 per cent. Although some wood-burning equipment is specifically certified for efficiency, most is not. Also, most wood-burning appliances are manually operated, not automatic, and so the practices of the operator will affect the efficiency actually achieved.

(Source - Canadian Govt. (I have and EPA source for USA on other computer showing similar #s)

to the higher efficiency equipment.

Quick link to recent UK story on what is possible to reduce consumption:

I have just installed a Westfire (Danish made) 21 5kw woodstove. It's stated efficency is 78%.

My estimates are that this will cut my gas consumption by 80%. I am also hoping to see a small reduction in electricity usage as I have a stove top kettle which is used to top up the electric kettle and manually fill the dishwasher and washing machine with 2.5 litres of hot water from each fill.

At present I am mainly using scrap pallets - untreated. These are a mix of hard and soft wood. I can get 17 6kg pallets in my car which will provide 4/5 of my heating needs for a week

Like other renewable energy sources, wood energy is best analyzed in a local or regional context. Macro analysis is of limited use. It also helps to bring some background knowledge to the task of analysis to avoid distortions in the results. For example:

"(Due to larger amounts of creosote and much lower wood fiber density in softwoods, they are not suitable for conventional firewood and I assumed are not used for heating –in a more advanced analysis this assumption could be relaxed as people could harvest softwoods and replant with hardwoods at least to some extent and/or install external wood burners)"

First, creosote is not a component of wood but a byproduct of incomplete combustion. Second, people living in large parts of western and northern North America have only conifers like fir and spruce and lighter deciduous species like aspen to burn and they make out fine. Softwoods are widely used for home heating. Half of the firewood I burn is poplar/aspen, which has about the same density as spruce. Third, it is a mistake to assume that hardwood (deciduous) trees can be planted to replace conifers or even that this would desirable. Note that advanced technology residential heaters of the kind that have been available for twenty years can burn softwoods just fine. The idea that only hardwoods make good fuel is traditional knowledge that is no longer valid.

"Freshly cut wood has over 60% moisture and therefore takes much more effort to release the energy in the wood fibers. Seasoned wood approaches 20% moisture content"

You need to be careful which method is used to express wood moisture. Using the wet basis, the normal moisture of live trees ranges from 30 per cent to somewhat over 50 per cent. The ideal firewood moisture content is 15 to 20 per cent.

"Wood stoves and furnaces average about 55% efficiency."

While that is true for old style conventional stoves, the advanced, EPA certified stoves average around 70 per cent efficiency.

But the main problem I have with the article is the underlying straw man argument, namely: If everyone heated with wood the forests would be gone and the air would be too polluted to breathe. That is certainly be true in relation to the forests, but then no one has ever suggested that wood is a suitable fuel for everyone everywhere. Like the other renewables, wood is a local fuel and when considering its potential, it is best to analyze it at that level.

Also, dense smoke emissions are not inherent when wood is burned. Using EPA certified stoves greatly reduces smoke emissions. But wood is still a lousy fuel for large urban areas, partly because of air emissions but also because the cost of fuel transportation and storage make it impractical.

I suppose one could heat with pine but you have to be a donkey to keep toting in large quantities of fuel.

My wood heater is not that big. I have three more heaters that can take larger sticks but no surface to cook on. Wood cookstoves do not usuall6 have large fireboxes either.

Yes some must use pine. There is little except in the nore mountainous part of the state.

Wood ashes will soon be valuable and softwood I understand has far less ash value. Wood ashes make lye. A good disinfectant. Make soap. If you can't keep your areas sanitary then disease and sickness can take a big toll on your health. Homemade soap is what we used in my past.


Calculation has to be made for the large amount of physical labor required to use wood as a fuel. Some mechanical aids are needed; chainsaw, tractor and log splitter. An animal can be substituted for a tractor, but splitting cordwood is arduous, even for a teenage. The best firewood is standing dead hardwood, not fallen wood which is often rotten and maggoty. Standing dead wood cannot be cut with an axe or hand saw. It is just too hardl the axe will bounce off.

Green (wet) wood is poor firewood. A large amount of the energy contained within the wood itself is necessary to boil off the water in green wood. This 'cooking the wood' means a larger amount of wood is actually needed to provide heat than what would ordinarily be indicated. Wet wood also creates a large amount of creosote. This is very toxic and can cause chimney fires. There is a lot of maintainence required to use wood as a heating fuel; the chimney has to be cleaned every year and all components carefully examined for places where hot gasses can escape and cause a fire.

Compared this to the gas furnace that can be ignored for years after installation.

Large amounts of wood heating users generate a large amount of air pollution. There are catalytic converters for wood heaters but this is an additional cost that must be added to the cost of use. Since the converters are expensive, many won't use them and the health care costs borne by the wood burning community as a whole for the pollution also have to be calculated.

America is becoming an 'old' country with a large percentage of inhabitants over the age of 60. Woodstoves are not for most of these; Americans generally have no physical fitness or strength regardless of age. If labor is hired, that cost plus any business costs must be added to that of the wood itself. In other words, wood is economical when the user can cut wood on property he owns and make it useable on his own account. An elderly population will have difficulty doing this.

I am now in a house in New Orleans that was built in the 19th century. There is no insulation on the walls or floor, the windows are so loose in the frames the slight breeze causes the blinds to flutter like flags even with the windows closed. There are millions of houses like this all across the south ... and the rest of the country. The last house I lived in in Virginia had no insulation, poorly sealed windows and doors, etc, etc. An effort to insulate and weatherize would be better in the long term as the 'heat gain' (and cooling gain in summer) represented by the insulation would be permanent. This is compared to exchanging one type of fuel with its attendent costs for another type.

Another issue - briefly - is that increased 'wood business' both from the standpoints of supply and demand would distort the marketplace. This is happening already in the market for pellet stoves and fuel. With more stoves installed the demand has made the pellets unavailable in many areas. Additionally, the pellets are a byproduct of the housebuilding business. 'Home' construction indirectly subsidized the pellets. As the building business has declined there is less building wood needed; what was a 'free byproduct' now has to bear all the costs that were originally borne by the building business' customers.

All fuel use in this country is on an industrial scale except solar - large enough changes to effect the marketplace would probably cause the market function 'undesireably'.

The President would have to appoint a 'Firewood Cxar',

Steve,I can agree with most of what you state except for this part:

"America is becoming an 'old' country with a large percentage of inhabitants over the age of 60. Woodstoves are not for most of these; Americans generally have no physical fitness or strength regardless of age."

I know of several oldtimers who still prefer and use wood. They gather it slowly during the off heating season. Of course they use chain saws and gather a lot of what is called 'rounds'. this is limbs that don't need to be split. Some have tractor mounted hyd. splitters.

I am 70. I cut my own. I split my own. Don in Maine does too.

As to age being a problem? Well that depends entirely upon the person's health. If you read some of the FoxFire series by Wiggington(from the recent past)., will note how many of the aged mountain folks he interviewed and wrote of with pictures , how many lived in small dwellings and used wood still and were content.

There are other 'older' folks who are unable to do anything. They are a result of a different upbringing(what we called 'fetching up')...and a different lifestyle. Most are sick and ailing. They are not the type who are resilient and fighters and live healthy lives....just as most older folks did way back.

So yes,,modern aged people raised in the city are pretty much unable to do anything for themselves and so I submit that likewise todays younger people have the same that are prone to failure,lots of strokes and heart problems..and they are NOT going to survive , no way Jose....

Accepting this article as valid then the following conclusions can easily be drawn about those who will survive or stand the best chance.

It will be those who have lived more sustainably in their upbringing. Those whose hands are hardened with work. Who have skills that are useful. Who live near their own woodlands and woodlots. Who don't take drugs and medications. Who can cook with wood. Who own the tools to allow them to fall backwards to earlier lifestyles. Those are men made of pig iron. Men who just don't know 'give up'.

There are some who post here at TOD and I suspect more who have become less active in order to further the plans they see as essential and was realized some time back here on TOD.

The writing was and is on the way. Those who are not already heavily into preparations stand IMO little chance of making 'the jump'.

Those IMO are the ones who contribute a great deal of conjecture here on TOD but ARE NOT TAKING away the lessons that are imbedded within the data and text...

The lessons: This country is spiraling down in many areas. There seems to be little leadership and most of what there is is counter produtive. The recent new president seems to be getting very poor advice. We see other countries dissolving before our very eyes yet we seem to think we are immune. This is the lessons and oil is what ramped it up to the point that it all started to fall apart.

What can one say then? What hasn't already been said? What can one do? If you don't have answers to the above then I believe you can start to kiss your buttocks farewell.

I am a doomer. Nothing leads me to be otherwise. I don't wish to be one. I watch closely. I read copiously. I got the message then.

Will it be bad? How bad? We haven't even started to go there yet BUT the recent events portrayed by Nature upon this area due to IMO Global Climate Change shook me out of my reverie. We are still digging out and already many didn't see the fortelling signs therein.

This is the way of modern man. Eyes wide shut. Stumbling down shuttered shopping malls. Driving like always.Using his vehicle as a virtual penis and terrorizing other citizens on the roads. Refusing to believe and not even 'listening'.This is 'chicken-man'. He is worthless and his make work job is worthless. He will fall first.
He builds his empire with ostentatious castles of vanity we call McMansions as well as his Humvee where he pretends to be 'hunter-man' and spends thousands to slay bambis. His wife has to take classes to learn how to light off the kitchen range or nurse offspring. He is not 'survival-man'.

His epithet is currently being written but there may not be a gravestone to engrave that upon. His destiny he figures lies in his billfold full of credit cards. Cards that his life circles about. Now he has lost his McMansion or soon will. His money in the bank draws almost nothing. His trade cradle(financial markets) is falling down. He is still not reading the signs of the future. He thinks someone else will fix it for him.Food is still on the grocery store shelves.
Life is still good for him, for now.At the moment.

Airdale-as always:
I could be wrong, I have been wrong before..
better wrong than be buzzard din-din

PS I sense I have painted a lot of the above with a certain amount of hubris for which E. Blair and others will surely chasten me, and for which sin I ask forgiveness, on earth and in the chaos to come....
So I ask, what is your answer?
Or from a recent movie; "What the f*&k have YOU done today."(Wanted-James McAvoy)

"Standing dead wood cannot be cut with an axe or hand saw. It is just too hardl the axe will bounce off."

Well, hand-saw and axe is what we used to cut down dead standing trees for firewood when I was a child. And what did your great grandfather use? Not a chain-saw: That is sure. I know Americans have gotten soft, but if you are really too soft to use traditional hand tools, give it up and exit using method of your choice.

If you NEED power-tools you will die anyway.

No they did not use an axe to cut large trees down.

I was there. We used a two-man crosscut saw. Same as the three I got hanging in my barn.

A good sharp two man saw can cut quite well. Up in the really big tree country and I mean like 15 foot diameter huge trees I saw pictures of them using axes(to start a cut) and then crosscut saws. Timber was very big back then but again no chainsaws.

Yes Ahmurkans have gotten really soft. Soft hands,soft feet and soft heads.

Airdale-the constitution is there to allow the people to control the government and not for government to control the people...

Forget who said of our founding fathers I think.So just where and when did all these 'exective orders' come from I wonder?


A picture is worth a thousand words:

Falling Big Timber


I am in my mid-50's and I cut down and split about 5 cords of mostly oak and locust by hand every year. It is not actually all that hard. A splitting maul, a few wedges, a torpedo and a big sledge should do it. Now splitting sycamore is ugly work. That will build you some strength. I do use a chain saw but it is quite doable to use a saw or axe and I have done both to some extent. It just takes a lot more time which I do not have. I have never yet used a power splitter as they are for old men and my father did not switch to one until he was 70. So I have a ways to go.


Written by steve from Virginia:
Calculation has to be made for the large amount of physical labor required to use wood as a fuel. Some mechanical aids are needed; chainsaw, tractor and log splitter. An animal can be substituted for a tractor, but splitting cordwood is arduous, even for a teenage. The best firewood is standing dead hardwood, not fallen wood which is often rotten and maggoty.

I see from reading the comments that advice about firewood is region specific.

I am in Arizona with Piñon Pine, a softwood, and Juniper, a hardwood, available on my property. Mechanical aids are certainly needed. I have collected, cut up, split, stacked and dried firewood for years using manual saws, a dolly and an ax. Splitting wood with an ax is easy, especially Juniper. Dry wood splits easier than wet wood. Cutting large tree trunks with a manual saw is the most difficult part, but is certainly doable given effort, time and persistence. A chainsaw speeds up the cutting of large logs. I avoid tree trunks larger than about 16 inches in diameter because the effort that I must expend on them hardly seems worth the resultant fire wood. Trees rot here, but there are no maggots. There are some insects that chew beneath the bark making bark easy to remove. Some worms tunnel into the wood, and termites are sometimes present. The semiarid environment and cold winters (0 F to -10 F) seem to control the insects. I prefer to use pine as firewood because the wood is easier to cut and bark beetles killed hundreds of them on my property in 2003 and 2004. I will not be able to use all the dead wood before it rots. I cut up firewood in the spring or summer, place logs in sunlight for a few days to dry and stack logs in my garage to keep them dry.

Creosote forms in a chimney when wood is burned incompletely at low temperature. It is easier to get a high temperature in my wood stove with Juniper than pine, but I can do it using split pine and bark. Pine bark stripped off the log burns hot and fast.

My noncatalytic wood stove is rated as 63% efficient which does not include heat released from the stove pipe into my house. The firebox is partially lined with bricks to help raise the temperature and provide thermal mass.

"I cut up firewood in the spring or summer, place logs in sunlight for a few days to dry and stack logs in my garage to keep them dry."

As you said, everything is regional. Here in Vermont in recent years (very wet Junes and Octobers - climate change?) I find it harder and harder to get the fire wood to dry. Wood (red oak) that was downed 3 years ago, cut (but not split) and stacked in my woodshed (under a roof) from before last winter (15 months ago) is still not dry enough. I now split it and lay it in front of the stove for a day or so to get it dry enough. (I am much more motivated to split right before use, also it splits easier when cold and dry.) A few years back I could stack firewood (cut, from deadwood, to stove length) outside (no roof) in the summer and and it would be ready to burn in late winter. Not any more. I've also been getting more creosote in the chimney if I'm not real careful.

everything -regarding firewood - is regional

In northern Virginia there is maple and 'tulip poplar' (the tree that supplies 'Poplar' in lumber yards), locust, hickory. some ash and oaks of various kinds in cleared areas. When I was growing up most of the people in my area heated with wood. There was pine, but it doesn't put out much heat. Oak is good, not to hard to split but not so available. Locust is easy to find but very tough to cut and split. I used it to make levers and posts. Poplar and Maple are easy to split and not too hard to cut. Live trees - which are what most cut during the 'axe and saw' era - are fairly easy to cut by hand with an axe and saw. Even oak trees are fairly soft when live. Needed are TWO people for the saw and that is real work. Cutting the tree down is step one. Cutting up the trunk and large limbs is a much bigger task ... :)

The toughest tree to cut and split is Elm without a doubt. A machine is requied to split it. I almost never used a splitter, but a sledge and wedges. My father borrowed one - a long time ago - and I used it to split some elm that had defied the hammer and wedges.

I live in suburbia, now and nobody where I live has a chance of being able to heat their own houses with wood, by cutting and splitting firewood that is. Everyone is too fat ... they could burn furniture or paper money ...

I cut some wood last year but it is inefficient unless the house, the stove and the wood are all 'in their proper places'.

There is some family land that is still wooded so it could be done. Transport of the wood to 'civilization' would eat up any energy saving, however. Same with using wood as a transport fuel. It is possible but does not return very much energy. Turning 'wood chips' into biomass or ethanol requires a lot of steps. The steps are not considered; unless there is a second use for large quantities of wood, there is nothing to 'subsidize' the use of wood as biofuel feedstock.

When I used wood in New Mexico (about 3 cords per year, high altitudes are almost as cold as the Northern states), hardwoods were virtually unavailable. The primary fuel woods were Juniper, and Ponderosa Pine. I loved Aspen when I could get it, as it burns very cleanly. Much more was available then the demand. The need for thinning of forests that had been protected from fire is huge. The spruce and fir grows at higher elevatons generally over ten thousand feet, and these forests generally do not need thining.

the point of this analysis was to highlight just how much we are subsidized by fossil fuels, including the heating of our homes compared to methods widely used just a few generations ago.

but I suspect the 'ballpark' that it is in will become more relevant in the years ahead.

Hi. Just continuing the debate regarding the efficacy and efficiency of wood as fuel with my new video...

I was trying to remember your website the other day - was going to see if you'd posted anything new. Couldn't remember the address and could not for the life of me latch onto any combination of words that would bring your site within the 3 page limit of Google. (That is, if a web site does not show up within the first three pages of a Google search, it simply doesn't exist).

Pellet stoves sales have been exceptionally strong in recent years, but there's a dwindling supply of wood pellets and their price has increased sharply -- now running in the range of $6.00 a bag versus $3.50 just a few winters ago. It seems unlikely the situation will improve anytime soon.


On this side of the border, police had to be called to break up a scuffle at a local hardware store when rumours spread that a tractor trailer load of pellets was about to be received.

On a related note, nine out of ten homes on beautiful Prince Edward Island are heated with oil. Earlier this fall, PEI's CBC evening newscast, Compass, ran a four part series series entitled "Escape from oil", accessible at:

For more information on the Cansolar panels featured in the fourth segment, "A bright idea", see:


Hi Paul, that Cansolar panels are pretty cool even if the place has an unfortunate name!
I wonder how simple it would be to make an air to air heat exchanger which could be fed with an earth pipe and mounted on the cold side of the house. With some vents the cansolar panel on the roof could be used as a solar chimney to draw cold air into the house through the earth pipe. This way the system could offset heating demand in the winter and cooling demands in the summer.

I don't think there would be sufficient air flow to make any appreciable difference. I suspect you would need something more along the lines of a whole house fan.



I am living in Scandinavia and not so familiar to the feet-stone-gallon-cord system. However, growth in forest in the metric system is usually measured in cubicmeters "with no air inside". When splitting wood you get air between the logs and you get "more" cubic meters of stacked wood due to the air inside the stack of wood. The difference might be as much as 1.6-2 times in volume depending size of the logs.
To me it was not obvious if this was taken in account in text.

A lot of forest is grown primarily for saw logs and pulp. Fire wood comes as byproduct of that. If for instance spruce is replaced by hybridaspen or hybridpoplar growth can increace by 3-4 times and 4-5 times. This gives harvest cycles of 20-25 years for hybridaspen and 13-18 years for hybridpoplar. If you live further south of Scandinavia you can use other trees that yield even better.

Sweden has 1/8th the population density as a state such as New York. There are more options for biomass for Sweden than for much of USA.

Interesting. Sustainable energy is the future no matter how you look at it.

Some facts about wood:

On average, a natural forest (not grown by humans) can sustainably produce 2 tons of wood per acre per year. A human grown and managed forest can produce upto 5 tons of wood per acre per year.

Each kg of dried wood (20% moisture) contains 20 MJ energy. Therefore one acre natural forest can provide 40 GJ energy per acre per year.

A quadrillion is equal to 1 million billion or 10 power 15.

To get 7 quadrillions of energy that the article say is used by usa to heat homes there is a need of 175,000 acres of forest. Given the size of usa its not a large amount of land.

I can't be wrong about each kg of wood providing 20 MJ energy as I had found that on many sources and as one liter petrol is about 33 MJ, one kg hay has 2000 digestible calories or 8.4 MJ digestible energy, one kg wheat has 3400 digestible calories or 14.28 MJ digestible energy, one kg coal has about 22 MJ energy etc (some examples of organic stuff).

I also can't be wrong about 1 acre producing 2000 kg wood per year as 1 acre is a pretty much large piece of land having 4000 sq m land and in natural forests 160 trees per acre and in human-managed orchards 400 trees. There can easily be 160 trees in one acre in a square format with a distance of 5 m between trees. At 160 trees per acre there should be a 12.5 kg wood per tree per year, given density of wood as 0.6 gm/cc it means a cube of 27.5 cm on each side (one hand plus one third hand).

Note that I am counting branches and fallen pieces of wood too that are of not much use in furniture making but are good enough for burning.

Btw I also found out that one acre of natural forest also produce 600 kg fallen leaves (ofcourse mostly in autumn). These can be fed to goats to get an equal amount of solid waste, solid that is other than urine and moisture according to the law of conservation of mass.



Good one.. made me come up with a variation..

"Growth is only half of the picture"

Interesting analysis. But I am glad that the ash that comes out of my wood stove is a lot lighter than the wood that goes in. The same applies to goats. Mass is still conserved, but most of the carbon exits as a gas (CO2)...

In Sweden, wood pellet furnaces have almost completely replaced fossil fuel furnaces, in areas without district heating. The furnaces are at least 80% efficient, many claiming 90% efficiency. Wood pellet energy content is high, about 7450 BTU/lb, since moisture content is below 10%. The pellets are made from sawdust and other waste. While they do require some energy input in refining, they enable use of a resource that would otherwise be wasted.

The problem, at least locally, is one of supply and price. As odd as this sounds, it's now cheaper to heat with oil and in some cases electricity than wood pellet, assuming you can find any.


It would seem that wood heating will never be as thermodynamically efficient as geothermal-assisted heat pumps.

And that wood can be converted to bio-coal, with electric power co-generated during the conversion process, resulting in a readily transported, readily stored fuel that can be used to fuel dispatchable power to complement volatile "use it or lose it" power sources such as wind turbines, CSP, run-of-river hydro.

Of course, whether using firewood or biocoal, directly or via the grid, its only sustainable renewable energy if the wood is grown in a sustainable, renewable fashion. The most appealing approach for that is coppice wood production, where the tree is cut back down to leave just the main stems, but the root system is left intact, so that it grows out again much more effectively than planting seedlings.

And with coppicing in rows along a level elevation, so that for a species with, say, a 5 year harvest cycle, one out of 5 rows are harvested each year, it is possible to "farm" coppiced wood even in the hilly terrain of Appalachia.

I realize there is lots of state and Fed forest land. But there are also many small holdings like mine (57Ac). Would it be worth it to me to log my land for firewood? Let's say I got 50 cords at $300/cord - $15k. My answer is no, with the reservation below. In my area there is about a 40 year cycle of harvest to harvest so this would, essentially, be a one shot deal. I would be left with denuded land and a lot of work to re-establish the trees.

However, if George Soros and others are correct that there is no bottom to our financial quagmire in sight, I could see having to do at least some additional harvesting beyond personal use for either barter or income. Even this assumes fuel is available for saws, splitters and trucks. At the current price, doing it by hand is unrealistic.


This spring, saints willing, I am going to be taking a hard look at pyrolysis heating/cooking methods.

Farmers around here push down timber into piles and burn it. A lot was burned after Ike came thru. And now that is multiplied many times. Huge piles are everywhere. Almost none will be burned for heating.I don't know where the brush will be hauled off to. No one has said. I suppose a landfill.


Some years ago, This Old House had a short segment about a trade show in Germany. What they showed was a pellet furnace (probably hydronic) that used pyrolysis of the pellets rather than burning them directly. I thought it was neat even then.

A couple of words on the "old guy" front. I'm 70 like you, Lynford is too IIRC and a few others. I've been burning wood for heat for about 35 years and cutting and splitting most of it (all of it for the last 29 years). Way back my wife even had her own small chainsaw to help out. I like working in the woods - even on a mountain! Frankly, it keeps you young. Why go to a health club or buy exercise equipment when you can do something needed?


Todd and Airdale,
I'm pushing 70 and find wood collecting, preparation, and use to be therapeutic. I was recently teaching my 15 year old city boy grandson the art of splitting logs. He could not believe an old man like me rarely used a wedge and could hit the exact spot required to efficiently split red oak cuts up to 3 ft. in diameter. Once i taught him how to "read the wood" he was able to split quite effectively with a wedge, but mastering the art of the swing with a splitting maul comes only with experience. He seems intrigued by the whole process and maybe i can get some assistance next year, if he looses that damn I-pod thing he has hanging around his neck all the time. Took him down to the swamp last summer, sat him down, had him put his fingers down into the earth, told him to pretend they were roots and told him to listen. Damn near blew his mind. Natures symphony is edifying to them that never heard it.

You guys should know that you are among my favorite players on this site. Wonder if our advanced age allows us to see things a little calmer than these very bright young folks who comment with such vigor. Hell, one of them might just find the magic elixir. i am a doomer though. Everything I have read over the past 35 years convinces me that change like humankind has never seen before is in our near future. Reminds me of Buddha teachings. At some point one attains a level of independent knowledge that no longer needs confirmation from others. Fortunately, us older folks have a front row seat, and when we yell out, "What a Ride" we don't really give a damn what they think.


Well put Mr. Cretin(real name?),

Ahh the elixir? I dig ginseng,,whats left of it when the berries are dropping. I put it in a quart or pint jar of moonshine(if I have any and right now I don't) or any other good Kentucky bourbon. One root to a half pint in volume..Longer it sits the better is gets.

A sip once every two days is good to go..but I mostly take mine when the mood strikes and I preserve it much as I can.

I think you have 'broken the code'.

Now my son would simply NOT go out to help me pick up hay bales. He outright refused. He wouldn't drive my little hay racking tractor either. He ended up pretty much not wanting to perform any work period.

So the result? He is way way way overweight. He is already in worse health than I am and he is about 46. Too much to do with those Pediatricians my wife took him to. No cows mild the guy said. None of this and none of that. Had to drink artificial milk. Hates green stuff.
He keeps that Ipod in his ear. He missed a lot of what life is about.

He never could handle a horse either. I always had horses but he somehow took to his mothers ways. But near as I can tell he is just the same as all the rest of the yuppies. Or genXers as they might be.

Thing is that I look back on some very good memories. He looks back on nothing. I grew up in the best of times. I think he grew up in maybe the worst. He is never going to give me any grandchildren.

But I am grateful for that ride you speak of. And yes I don't care what they think either and I often tell some that. They don't seem to be in my world and understand. They are always saying "ohhh let me grab this cellphone call"...and I turn and walk away. Whats the use?


Todd and Airdale,
I'm pushing 70 and find wood collecting, preparation, and use to be therapeutic . . .

You guys should know that you are among my favorite players on this site.

Is it weird that I'm 20 years younger than you guys and female, yet the older guys on this board are among my favorites, too? I include Don in Maine in that...


Lilith is 50?

Wow...when I was 55 I thought I was in my prime. Thats when I spent 3 years building my loghouse(4500 sq ft under roof) all by myself.

I was tough then.Now I am just a shadow of that so I use my energy more wisely and don't waste it on silliness or things with little payback.

At 70 one starts IMO to begin to see the end up ahead. It can sorta get to be heavy in your mind. Thats the time to do something very relaxing.Like go fishing for a week. Drink all the beer you can while fishing and cook fish at noon and steaks at night.

But so far that hasn't materialized as yet. I have one boat and today fixed a guys computer for another boat.In a few weeks I am definitely going fishing.

Then it will be time to start planting. Potatoes first.


Well thank you young lady !! The geezer squad is quite right. In a society that answers every problem with a pill, splitting wood is zen. Your anger, your frustration, your doubts are gone. The body kicks in and the mind gets the rest it needs. I never come in from the wood yard in a bad mood, I look back outside and what I see is that I have been highly productive. So many of the ills some people face actually seem much less of a problem with some fresh air and work. Depression is a big one, anxiety another, hard to be either when you made a big pile of split wood, raised a good sweat, and are tired.
Mostly you end up hungry. Grin. Scott Nearing, when he went to friends to have dinner always wanted a spell at the wood pile first, than some home grown food and dandelion wine, and talk of economics into the wee hours.

Rube, dead on, my wife still gets uncomfortable sometimes when I'm gone in the woods for hours. In the summer I can head "down back" just after I get up and do nothing but just be. Don't come back till well after dark. It's a place where I know inside I am a part of it and it is a part of me. I've said it here many times, I have the stars at night and the wind in the trees and I am a rich man.

Airdale is right, at this end of the line, we've become real people. we have perspective. We've kind of meshed that outside shell that was for other people to see and the real inside parts. It's not always pretty but it's us. We are what you see, no longer any need for pretense. We are not quite so passionate. Seen so much it is hard to get really excited. I do enjoy the passion I see here. Passion can be fun to watch, and I find I chuckle a lot, which is very healthy.

Spent the day, shoveling the new snow. Driveway now looks like a tunnel. We got pounded this winter, got close to another 16 inches yesterday. Heavy wet snow, so many are still without power. And so it goes.

One thing about geezer hood, is that you begin to understand you can deal with anything life throws your way, from a billy club in Chicago in 68, to the birth of your first son, and the death and passing of loved ones. I still wake up to face each day. I have no fear.

Wrote that and filled my jim beam and loaded up the stove, some really dry oak. The old hound dog saw me and got up to come closer to the stove, his 2 favorite cats joined him as the splayed out on the floor next to the stove. Cats and dogs, look like road kill next to the stove.

Observation and opinion is pretty much all we are really left with. Thanks for letting me share mine here.

Don in Maine

Why go to a health club Todd asks?

Why its the 'yuppie' thing to do. Shows you can burn money and ride a bike to NOWHERE while plugged into your BlackBerry or and Ipod.

Pure yuppism..rules us now. Elects our political folken.

The body is is the head then.

Airdale-I could be wrong, but on this I am not. I saw it coming. I ran the other way. I sneered a lot. Did no good.

Rube Cretin seems to fit at this point in my life. You see, like you, I have an estranged wife who spends most of her time in the mall, and i am exploring the happiness and pleasure born of seclusion. I retired at 53 when i realized i was spending my life energy for an illusion. My children all see me as a relic, because i am only available for a need not a want. Interesting being stoned in your own house for being a prophet of doom. Guess it takes a some living to recognize and know the specific circumstances of what should be cultivated and what should be refrained from. Me, I'm just trying to get along. Be alert, Rube may visit you soon. You have left lots of tracks.


Rube Cretin seems to fit at this point in my life. You see, like you, I have an estranged wife who spends most of her time in the mall, and i am exploring the happiness and pleasure born of seclusion. I retired at 53 when i realized i was spending my life energy for an illusion. My children all see me as a relic, because i am only available for a need not a want. Interesting being stoned in your own house for being a prophet of doom. Guess it takes a some living to recognize and know the specific circumstances of what should be cultivated and what should be refrained from. Me, I'm just trying to get along. Be alert, Rube may visit you soon. You have left lots of tracks.


Rube Cretin seems to fit at this point in my life. You see, like you, I have an estranged wife who spends most of her time in the mall, and i am exploring the happiness and pleasure born of seclusion. I retired at 53 when i realized i was spending my life energy for an illusion. My children all see me as a relic, because i am only available for a need not a want. Interesting being stoned in your own house for being a prophet of doom. Guess it takes a some living to recognize and know the specific circumstances of what should be cultivated and what should be refrained from. Me, I'm just trying to get along. Be alert, Rube may visit you soon. You have left lots of tracks.


Rube Cretin seems to fit at this point in my life. You see, like you, I have an estranged wife who spends most of her time in the mall, and i am exploring the happiness and pleasure born of seclusion. I retired at 53 when i realized i was spending my life energy for an illusion. My children all see me as a relic, because i am only available for a need not a want. Interesting being stoned in your own house for being a prophet of doom. Guess it takes a some living to recognize and know the specific circumstances of what should be cultivated and what should be refrained from. Me, I'm just trying to get along. Be alert, Rube may visit you soon. You have left lots of tracks.


I'll leave a light on for you.


Softwoods are used for firewood wherever hardwoods are scarce. You just have to clean your chimney a little more often. A cord as actually sold is about 90 cubic feet of wood and 38 cubic feet of air. I use about 300 cubic feet per winter to heat my house, which has had five inhabitants, but is now down to my wife and I. All of it, and most of the wood used in my part of northern California, is mortality. Most of this year's wood was lodgepole pine. In theory, the annual growth in the United States of 23.7 billion cubic feet could heat about 75 million homes like mine, but I agree with comments above, that the last graph shows where wood heating is feasible for a large percent of the population.

I think the whole point of the article is that wood heat is just not sustainable.

There may be small pockets of sustainable wood heat in the U.S. but generally speaking wood heat will result in total deforestation of the continent.

When I try to raise the spectre of peak oil and it's consequences most people always pull out the cunard about wood heat. Thank-you for clarifying for me the consequences of believing wood is a viable alternative.

I heated with wood for 20 years. It took me five years to learn how not to burn down my house. Imagine the carnage that would ensue in a large shift to wood heat. And I suspect most people new to wood heat would use softwoods. The creosote build-up would be horrendous. The chimney fires catastrophic.

Wood heat is sustainable because it is self regulating. Hardly anyone is going to drive more than 50 miles to get their firewood, and barring a complete collapse of our society, the main parts of the large trees will be more valuable for timber than firewood.

For those looking to burn wood more efficiently try:
I just ordered some wood yesterday. Most of it oak and compared t o elm it has burned longer with fewer trips out during the day. I recommend a mix of soft and hard wood for efficiency. As for pellet stoves I think the distribution issues will become a factor soon. You can always burn your furniture in a pinch. Pellet stoves also require electricity to run. This is not very helpful in a blackout.

I am posting some content that was recently circulated around here by the FSA and Extension Agents regarding damaged trees.
Trees that have suffered extreme damage may not have lateral branches remaining. Without laterals the only choices are immediate removal, making topping cuts with plans to replace the tree within a couple of years or making topping cuts and accept liability into the future. Topping cuts are never recommended for the long term survival of any tree. Even though some new growth will develop at the point where stubbing cuts was made, decay will occur and in conjunction with the colunmn of decay in the trunck will suffer significantly higher rates of breakage in the future.

Tree species differ in their reaction to ice loads. River birches,silver maples,oranmental pears,white pines,willow and many other species suffered disporportionally more damage from the ice storm. These species grow rapidly, reproduce early and are short lived. Other trees like bur oak are long lived. They invest their energy reserves in slower growth that is more durable with reproduction starting at a later age.

The Easter Freeze of 2007. Some tree breakage can be traced back to another mean trick of Mother Nature. It will be two years ago this April that we experienced a record breakihg plunge in temperatures just as we thought spring had arrived. This freeze caused trunk and branch cracking, especially in young trees so that they were too weak to withstand the effects of the recent ice storm. It also killed some or all the flowers on many of our trees. As a result they produced no fruit in the fall of 2007. In 2008, these trees overcompensated and with the help form a good pollination season produced abundant fruit.
On trees like ash and crabapple, these fruits persisted well into the winter, adding to the accumulated weight on the branches during the ice storm.

Now most of these is in regard to homeowner and orchard plantings.
But there are some takeways. Lateral branches are important. Topping cuts and trying to prune is likely a waste of time. Many of the forest trees therefore are lost. Those who are native to the area may survive but never like before. The huge very old white oak I have always favored in the woods close to my houes and where I buried my favorite hound has lost huge amounts of lateral limbs. Yet the top is still there. The report further states that new growth as a result of limb loss will never be very strong or worthy. This part was embedded further in the lenghty newsletter.

I fear that much of our woodlands are in deep trouble.

The other takeaway is that nature is capricious yet we have done our part to destroy the environment horrifically. Nature is repaying the debt. It is being unpredictable. In the last several years here I have no memory of some of the events that have occurred in that time. Floods,rains,lost crops,wet springs, cold falls, and now three whammies in a row. This being the worst.

As our trees fall and are shorn the winds will raise havoc with the soil Already a lot of roofs were blown off three years ago. Mine included. The patterns are changing. They are not getting better. Farmers are not helping by dozing down woodlands and fence rows to get more crops yields. Given free rein I think they would destroy every tree in sight. I know one fat farmers ahole who brags, "I would rather cut a tree than eat a meal!"...I say that he has missed very few meals but he has cut a lot of trees. My dad sharpened his chain saws. He is an imbecile. He is not alone. The government programs that used to tout conservation is no longer a voice that I hear in this land. They have gone silent on 'sod busting' as well.



On the other hand, this sounds like a wonderful, once in a lifetime opportunity for someone with exceptional farsightedness and a generous, unselfish heart to buy and plant a big bunch of black walnuts, and maybe some sugar maples, persimmons, and other native fruit and nut trees. The woodlands will have been cleared out sufficiently to give these room to grow. 50-75 years from now, people will look back and bless the memory of the one who planted them.

Softwoods can provide fuel in the form of pinecones which burn rather quickly. It's easy to collect a couple of buckets of them. I'm not sure what they do with all the throwaway newspapers but surely they could be made into slow burning pellets.

Right now it's summer in southern Australa and I'm cutting and stacking heavy eucalypt branches that have fallen in storms. In winter those storms consist of sleet and can last for three weeks. Last July for example I guess I would have used a tonne of wood. This year I intend to experiment with heating a smaller volume of air using removable curtains as room dividers. I'll also get a carbon monoxide detector that gives warning beeps.

Note this is all because I have free firewood and I suggest it is not sustainable long term for a large population. Fires generate particulates, tars, fire hazards, smoked out neighbours and general respiratory distress. Smoke stinks up your hair and clothes. Stumbling around with axes and chainsaws invites accidents. In a perfect world we should all have passive houses with sparingly used heat pumps powered by low carbon electricity.

Note this is all because I have free firewood and I suggest it is not sustainable long term for a large population. Fires generate particulates, tars, fire hazards, smoked out neighbors and general respiratory distress. Smoke stinks up your hair and clothes. Stumbling around with axes and chainsaws invites accidents. In a perfect world we should all have passive houses with sparingly used heat pumps powered by low carbon electricity.


Chainsaws are dangerous little bastards, almost entirely necessary if you intend on hauling in wood in any appreciable amount. Axes can be pretty bad too, but (unless you do something really stupid) they won't kick back into your face or shoulders. I wouldn't trust most of the people I see out and about with either of them. If you use a wood stove, you smell like wood smoke - period. I like the smell myself, but I'd guess most people don't. Passive solar, highly insulated houses with a small backup system would indeed be the preferable route. I would prefer the backup be an active solar water storage system (which would also heat water for other use). But we're so far from preferable it's almost not worth mentioning.

If you use a wood stove, you smell like wood smoke - period.

I sure smelled like it during the last power outage. Everyone else I ran into smelled like kerosene.

Home heating with wood?
It's not hopeless if everyone decides to live in Passive Houses.

There are 150 million dwelling units in the USA. The average area is 1500 sq. ft or 150 m2. A typical Passive house uses ~30 kwh per year per m2 for domestic hot water and ~25 kwh per year per m2 without considering solar space heating.
Cooking is not included here so the total is 55 kwh per year per m2.
So the total is 150 million x 150 m2 x 55 kwh per m2=1250 Twh.
The efficiency of a pellet stove is ~80% so we need ~1500 Twh or 5 quads of energy--5 quadrillion BTUs divided by 13 million BTUs per ton of pellets= 385 million tons of pellets.

North America currently produces about 300 million tons of roundwood(trees) used for lumber, paper, pulp, etc. This is 80% of what is needed but really pretty close to what the US
would require if all houses were Passive Houses.

So it is certainly theoretically possible, IMHO.

One of my concerns is that not only do the cellulosic ethanol folks have their eyes on wood, but also the folks who want to replace coal for electricity with locally grown wood. We really don't have enough wood to do all of these things. They may sound renewable, but they aren't really, on the scale that folks would like to do them.

I agree it is a matter of scale but it's also a matter of efficency and use. US corn ethanol could probably increase from 8 billion gallons(today)to 15.6 billion gallons by collecting a sustainable amount of corn stover(per USDA).

15.6 billion gallons of ethanol is equal to 10 million GGE, basically E10 which all cars can run on.
The US wastes 145 billion gallons of gasoline per year, so in the present situation ethanol would help with pollution issues and as an offset but we are far from replacing gasoline with ethanol.

Now there's always the switchgrass and miscanthus cellulosic ethanol out there but let's ignore that. Corn ethanol
produces DDGS animal feed so just consider the ethanol as a 'waste product' of the agricultural system rather than an energy crop.

As with Passive House we need much more efficient technology to make further reductions. Existing hybrids are twice as efficient as regular cars. Beyond hybrids there are fuel cell PEM ethanol cars which are 1.5 times as efficient as hybrids, so then we are talking about 50 billion gallons of gasoline equivalent energy instead of 145 billion gallons.

Do we really need to drive 12000 miles per year per car? A 33 mile per day average US commute x 200 work days a year is 6400 miles per year cuts us down by almost 50%(not to mention car sharing). A reduced energy lifestyle is part of Passive House.

Now we are down to demanding 25 billion gallons of gasoline equivalent energy per year versus 15 billion of 'renewable' corn ethanol(10 billion GGE).

I think there is more reason to concentrate on technological efficiency and lifestyle than to worry about the resources which no amount of worry can increase.

Yes, clearly wood burning can only be one part of any future sustainable way of staying warm in the winter. My first vote is for super-insulation and passive and active solar.

And of course lower indoor temps, especially at night, big comforters and efficient sleeping bags, more people per bed (oops, never mind), more people per square foot of living space, heat exchangers, geothermal...

The problem of particulates is quite a problem in urban areas, but also in mountain valleys where you easily get inversions.

In general, people tend to look toward the next thing they can burn, rather than thinking about other changes that would make it less necessary to burn anything (or much of anything).

I live in Minneapolis and remain on the fence about whether to get a wood burning stove. Even the most efficient ones are going to increase the levels of particulates my family and neighbors have to breath. We recently defeated a plan to have a wood-burning power plant built near by. The issues of particulates and of what else might go in when good wood was not affordable or available were of primary concern (along with shady dealings that seemed to be going on behind the scenes).

Have others dealt with similar issues in their cities and towns?

The city of Launceston, Tasmania had a subsidised upgrade scheme for wood heaters
The communal savings from wood heat are illusory if kids have to be carted off to hospital with asthma attacks.

The other big problem with wood stoves is they release massive amounts of particulate pollution.

There have many poorly designed stoves. Stoves with catalytic converters using extra air burn much cleaner, according to the EPA. However, there are some stoves being marketed, such as the wood boilers, which are intended to be loaded with wood and run for many hours. The only way to do this is to run them with very little air, so they do not burn cleanly.

The other part of the problem is that the installation may not be done correctly. If the stove pipe/chimney is not designed correctly, the stove won't develop enough draft to allow the proper amount of air into the firebox. In newer houses, which tend to be airtight, one must open a window to allow outside air to replace that burned. Some newer stoves can be plumbed with a direct vent from outside air.

E. Swanson

Gail's post is a reasonable analysis of using forest cut wood for heat.

But, what about using "waste wood" for heat!

The pie chart of annual wood usage shows nearly 1/2 of all wood going for "saw logs". Much of this is lumber for houses, but a good portion of this is for things like shipping crates, pallets, construction off fall, scrap from milling and cabinet making, etc. This country throws away millions of tons of waste wood every year, most of which gets buried in landfills.

The company next to mine at an industrial complex in Granite City, IL throws away about 5 tons of junk pallets every week. I see other companies in the area likewise filling 40 yard dumpsters with waste wood every week. My shop did have a non code wood heater that burned waste wood.

For nearly two years I used old pallets and wood scraps from the trash to heat a 3000 sq ft. shop. All that heat for no $$$. CO2 from my buring wood did not contribute to GHG since the wood decays to CO2 and maybe CH4 (even worse) in a landfill. My stove produced no visible smoke and had a chimney exhaust temp low enough that I could hold my hand 12" above the outlet and not get burned (flue gases and exchange air gases were almost the same temp. meaning great efficiency).

So my question is this:
How much could waste wood contribute to heating our homes?
Perhaps 10% of our US homes could be heated with waste wood products if this material was kept out of the landfill stream (IMO).

I doubt that the amount of wood recoverable from the sources you mentioned would amount to any significant percentage of heating needs.

To be used as fuel the wood has to be reduced to a uniform size, which is usually done by a shredder or chipper referred to as a “hog”. This allows the material to be handled by conveyors to feed a boiler.

The problem with waste is that you also get metal, glass, bricks and other contaminants that are rough on hogging and handling equipment. These contaminants make it difficult to use this type fuel for pellets. Although it may be possible to bag the hogged fuel for consumers, I do not believe it would be suitable for automatic feeding.

Breaking up pallets and manually and feeding the wood to a furnace is too labor intensive. On the other hand, if you are paying by weight for disposal, it makes more sense, as does anything that cleans up the workplace without adding too much additional work.

Breaking up pallets and manually and feeding the wood to a furnace is too labor intensive.

For years I have collected pallets for fuelwood & cut them up with a chainsaw. Doing so is less labor intensive than cutting up a tree. Nowadays, however, pallets are becoming increasingly hard to come by. There are people who collect pallets on a large scale & take them somewhere in large trucks & trailers. I'm not sure what they do with them. Perhaps they are recycled or maybe people are cutting them up & selling the wood. In any case, it's not as easy to get free used pallets as it used to be.

The intent of the article might be to show that wood heating is unsustainable but what was really shown is uninsulated houses are unsustainable. Insulating takes time and money. So does firewood.

The intent of the article might be to show that wood heating is unsustainable but what was really shown is uninsulated houses are unsustainable.

This pretty much says it all.

Insulating takes time and money. So does firewood.

Perhaps so. That said, I drive through rural Nova Scotia and New Brunswick and see five or six cords of wood stacked next to 1,000 sq. ft. homes, so I'm guessing firewood is cheaper than insulation.


Six cords? That's like burning an entire friggen house!

I know! Perhaps these folks keep two years of supply on hand, half of which is seasoned and ready for use and the remainder in preparation for next winter. Nonetheless, wood is a relatively inexpensive fuel in this part of the world, so there's no real economic incentive to reduce demand.


Insulation is cheaper in the long run, but it takes several years to get the payback. If humans behaved according to long run analyses, we wouldn't be where we are, and I wouldn't be a doomer.

It's very frustrating to see people behave irrationally. You would think they would make the right choice, but for whatever reason it just doesn't happen. (Actually, I try not to think about it.)


Insulation is almost unknown in California. The next door neighbors here are spending $1400 a month on electricity, almost all of that for heat. I myself am living in an OLD trailer, kinda third-world conditions but it's warmer than living under a bridge, and safer than any homeless shelter. Again, insulation is unknown. The poor don't have it because the poor are not considered to deserve it, and the rich don't have it because they just spend money like it's going out of style on heat.

A person rich or poor should be able to live like a king through the winters here with proper insulation!

I hear ya. A very good friend of mine once lived in a 1950's vintage mobile home in northern New Brunswick. It was heated electrically and had single pane windows that consist of multiple glass slats that crank open and consequently never closed tightly, so if you didn't cover them with plastic the wind would howl right through it. Winter temperatures in this part of the world routinely dip below -25C/-13F so, needless to say, he froze his ass off. I never asked how much he paid for heat because it was none of my business, but I have to assume it was substantial.

Best of luck to you.


Having worked as a chemical engineer in the pulp and paper industry for over 25 years, here are a few thoughts:

Wood waste such as sawdust, bark and other sawmill wastes are typically the cheapest fuel available. That is because there are few boilers or furnaces that can easily handle such material. It also requires bulk material handling equipment such as front end loaders and bulldozers and conveyors. Pulp and paper mills are equipped to burn this material for steam and power and can do so with very low air pollution. Wood ashes are valuable fertilizer that the industry does not recover. They usually end up in landfill.

Some of this wood waste material is now going into pellet fuel.
There is no real surplus of wood. Any additional wood consumption will compete with pulp, paper and lumber.

If there were no other uses of wood, we still could not heat 100% of our homes. However, there is room to improve forest yields. Private landholders, who own most timberland, are very inefficient wood producers compared to managed plantation forests. Managed plantations are declining because states have raised taxes on land and the standing timber inventory. Whenever possible, timber companies sell land for development to make ends meet.

Not having to cut firewood and manage a wood stove are features that define our standard of living. Cutting enough wood to heat a home requires the kind of time working people seldom have, although the exercise would do them some good, at least for those who don’t hurt themselves. This time would be better spent building a new ultra energy efficient house with a geothermal heat pump. Using natural gas in a combined cycle plant at 60% efficiency to produce electricity to power a geothermal heat pump would reduce heating energy by at least 60% compared to burning it in a home furnace.

In making paper, which uses the cellulose or fiberous part of the wood (except newsprint, which is all wood) the last water to evaporate in the drying process is called bound water, which takes extra energy to drive off. To accomplish this for firewood you would probably have to hold it at a temperature above 220 F or 105 C for many hours, which perhaps could be done with a solar dryer. Removing this water should add several percent to the heating value, and make the wood burn much faster and hotter. Has anyone tried this or read about it?

I once read a quote about a slave in America having more firewood than a nobleman in Europe. Can anyone tell me the source?

"There is no real surplus of wood. Any additional wood consumption will compete with pulp, paper and lumber."

Not true! See my comment above.

Millions of tons of wood are disposed of every year in land fills. This wood comes from left over pcs. from millworks, housing construction, old/broken pallets, home remodeling and wrecking, shipping industry (called dunnage), and even the railroads as they must dispose of millions of old ties.

This wood could be put to good use as a source of heat, but instead goes to landfills to be buried where it decays, producing CO2.


I was referring to first use or virgin wood having a supply/demand balance. I agree that there is a lot of post consumer waste from uses such as you cited that go to landfill.

I personally disposed of over a couple of tons of waste wood following the construction of my concrete house. A lot of the wood was in the pallets that the AAC blocks came on, which had to be very heavy to support a metric ton of block.

All of this material cost more to dispose of than the heating value of the wood. Some of it was heavy and full of nails. I had to use a Bobcat to put it in a dumpster for safety and time reasons.
Municipalities collect large amounts of tree trimmings which could similarly be used for fuel. Some trash departments compost this material and sell or give it away.

Your comment clearly states a major problem. When building, one often is in a situation where it's desired to get the job done fast. I've seen dump trucks full of logs cut from land under development, logs which were being taken to the dump. As things change away from "get-it-done-now" to "what can I do with my time to stay warm", I hope that much of that waste is put to better use. For example, I used pallets for walkways until they rotted, then cut the slats off them and took only the middle supports to the dump. The load was much smaller and easier to move. No problem with the nails, which went stayed with the middle beams. Of course, that approach is labor intensive, something the FWO won't want to do, until they are shivering in the wind standing next to a burn barrel...

E. Swanson

This time would be better spent building a new ultra energy efficient house with a geothermal heat pump. Using natural gas in a combined cycle plant at 60% efficiency to produce electricity to power a geothermal heat pump would reduce heating energy by at least 60% compared to burning it in a home furnace.

A combined cycle plant has a 'theoretical' efficiency of +60%(63%) but the real efficiency is less than 50%; they are sometimes called '8000 BTU/kwh' plants which is 42% efficient.
Grid losses are around 5%. A typical closed loop ground source heat pump has a practical efficiency around 330% which I assume includes energy for condenser pumping.
So the overall efficiency is .42 x .95 x 3.3=1.31 versus
a typical 92% efficient gas furnace;1.31/.92 is 46% more efficient.
The big unknown is exactly how much natural gas will be available in the future. I think we have much less than 50 years left at current rates of consumption;
1200Tcf/24 Tcf/yr for the USA.

Maybe somebody can make methane hydrates practical.

To be clear, utility power is typically a mix of two or more fuels, i.e., hydro-electric, coal, nuclear, petroleum coke, natural gas and, increasingly, low-impact renewables such as wind, solar, geo-thermal and bio-gas. Currently, about 20 per cent of the electricity generated in the United States is supplied by natural gas (much of it peaking due to a/c loads) and that percentage is significantly lower in Canada and I take it elsewhere. As stated before, if I heated my home with a gas boiler, 100 per cent of my needs are met by natural gas; in my case, 100 per cent of the electricity consumed by my air source heat pumps is sourced through green power, principally wind.


Reading all this got me looking around on the net about heating, and I found this really COOL site on rocket stoves, heating in general, considerations in heating high-mass vs. low-mass houses, etc.

Lots of cool stuff on stove design.

My property is along a river in New Mexico and is wooded. It is a Fremont cottonwood riparian bosque heavily invaded with Siberian elm, Russian olive & Tamarix. I occasionally cut fallen cottonwood limbs if they're in the way but don't kill the native cottonwoods as they have poor recruitment due to competition with the invasive species and I seek to preserve them. I heat with wood from the invasive species, in a homemade fireplace insert. I cut the wood with a Husqvarna chainsaw and haul it up to the house in a wheelbarrow. I'm in the market for a pony or donkey for pulling a wood hauling cart. The optimum length for my firebox is 28" and I try to cut it close to that length to minimize use of the chainsaw. A year ago I broke down & bought a hydraulic log splitter, since I'm not as young as I used to be for swinging a sledge. Unfortunately, 26" is the maximum length that will fit in the splitter, so I cut rounds that need to be split 26" & those that don't need split 28". We have burnt four cords so far this winter and still have about six weeks of wood burning season to go. This is more than we've burnt in past winters because my wife isn't currently working so she stays home & keeps a fire going all day. The fireplace insert isn't too efficient but efficient modern woodstoves are expensive. The fireplace heats the main part of the house very well, altho even with an electric fan blowing warm air down the hallway the bedrooms aren't very warm. I sleep in a sleeping bag during coldest winter. My son and I are cutting next winter's wood this winter. We let wood cure for one year before burning it. Virtually all the wood we burn comes off the property, altho I may get a permit from the BLM or Carson National Forest and haul in some juniper or Gambels oak. I claim that the wood harvesting off the property is sustainable and this is true with the following caveat: I am depleting the larger trees. Many smaller ones are growing, keeping biomass about the same, but the larger diameter trees are becoming more scarce. Most of the families in my neighborhood heat with wood, altho probably not exclusively. This is my woodburning story.

Just a couple of comments on a good analysis.

The portion of wood that is currently going to pulp/paper is decreasing as the world goes more electronic. In a peak oil world, this trend would likely accelerate since the world economies would shrink and less money would be available for printing. Similarly, peak oil would reduce amount of wood that would be used for building homes because people could not afford to build large houses, and new home construction would diminish. This woody material could then be available for heating.

Homes could be made much more energy efficient thus dramatically reducing the amount of heating required.

The least capital intensive means for combusting forest material would be in fireplace inserts or wood stoves. However, if the woody material could be burned to produce electricity (assume 40 percent efficient), and that electricity was used to run ground-sourced heat pumps, which are on the order of 400% (or more) efficient for heating, then wood could supply a much larger fraction of heat demand (perhaps three times more). Also, there is a lot of forest residue (small branches) which would likely not be used for home heating, but could be used for electricity generation.

If trees were grown in plantations, which is bad for biodiversity, but good for producability, then forests could could be much more productive.

I suspect that if you did the math on these factors, that the woody material could be used to heat all our nation's homes.

This all ignores the likely future use of forest material for liquid fuels, which would compete for resources with home heating.


I think you would get the most heat from wood by using it in IGCC plants with coal to power electric heat pumps, or gassifying it to run small CHP units powering more heat pumps. You could also use heating oil in a diesel engine with the wood gas being injected into the cylinder. According to this paper such an engine achieves a max efficiency of about 36% when using 10% diesel. The gasification process is about 60-70% with a total wood to electric efficiency of about 25%. Recovering the waste heat from the engine wouldn't be too difficult either, but the main point is that you wouldn't get that much more heat than using it direct in stoves. Might be cheaper and quicker to implement though, but if we are going to plant anything to make electricity might as well make it wind turbines, require no water and will produce as much energy in a week as a field full of energy crops will in a year.

Compare the distance above using PV and electric compared to biofuels.
Large scale wind power could deliver twice as much electricity at half the cost, thats where the attention should go.

It seems that you provided the efficiency comparison with the less efficient pathway that you explained.

We know how to produce electricity such that the electrical generation plants are 40% efficient (IGCC plants).

Ground-sourced heat pumps are 400% efficient (they are higher actually in certain situations, but practically speaking, 400% may be what would be achievable in practice using today's best heat pumps).

4.0 x 0.4 = 1.60 or 160% efficient. We need to subtract something for electricity generation, say 10%, and we are at 150% efficiency - compared to 55% efficiency used in the example. Home heating can be more efficient than 55%, as some stoves reach into the 70% efficiency range.

Thus, using biomass to make electricity and power ground-sourced heat pumps is in the range of 2 - 3 times more efficient than home heating.


We just had our oil tank topped up a few minutes ago. Since our last fill on October 24th, we've used a total of 160.6 litres (42.4 gallons), which is an average of 1.32 litres per day (0.35 gallons). Roughly half this fuel was used for backup support for our two small heat pumps and the balance for domestic hot water production (approximately 2/3rds of our DHW is heated with electricity and 1/3rd by oil).

Over the past 300 days, we've used a total of 312.8 litres, which means we're on track to getting our demand below 375 litres/year. When we bought this home in April 2002, it stood at 5,700 litres, so we've cut our fuel oil consumption by nearly 95 per cent thus far.

I was hoping we could have done better, but this winter has been considerably colder than last (several days with below -20C temperatures) and we had to run the boiler to supply heat during the four weather related power outages we've encountered so far this season.

I mention all this because so many people tell me heat pumps don't work in colder climates and I'm here to tell you otherwise. So what about our electricity consumption, you might ask? It has gone up since we added the second heat pump and the electric water heater; over the past 368 days, we've used a total of 11,671 kWh and as we roll into the next billing cycle we'll likely exceed 12,000 kWh. If all goes well, we should be able to get back below that mark as we move into the summer months. Come spring, I'll run our heat pumps in dry mode which I expect will use less electricity than our dehumidifer and I'll start washing our clothes in warm or cold water if need be.

For those who may be interested, our consumption history for the past 14 months is listed in the lower right portion of our latest bill:


Paul - Could you please describe your heat pump system? Is it deep or shallow? Any lessons to share? Manufacturers?


Hi George,

I have two 4.0 kW ductless air source units, also known as mini-splits. The older of the two is a Friedrich which is made by Fujitsu and the one I installed this past December is a Sanyo. The Sanyo is a high efficiency inverter system and is a much better performer for this one reason alone (don't even consider a non-inverter model). Their combined cost was $4,100.00 CDN or just under $US 3,300.00.

Basically, these systems consist of an outdoor compressor and indoor air handler (or multiple handlers), connected by refrigeration lines. They work well in homes that have hot water heating systems, infloor radiant or electric baseboard heat; in other words, homes that don't have conventional duct work.

This is the Sanyo outdoor compressor:

The Sanyo's indoor air handler is located on our basement level:

The Friedrich is located in the main floor living room and directs the flow of air across a large open centre hall, so a large chunk of its heat migrates to the second story.

In terms of recommended brands, I don't think you can go wrong with Friedrich, Mitsubishi (Mr. Slim), Sanyo or Fujitsu. Ideally, choose a model with a high SEER (some of these units now reach as high as 23 SEER) and a HSPF (heating season performance factor) greater than 9.0. My Sanyo has a HSPF of 9.3, which translates to a seasonal COP of 2.7, but some of the Fujitsus come in at 11.0, which means their COPs are greater than 3.2. In this case, for every watt of electricity that that is consumed, you receive more than three-watts of heat in return.

This is the link to my Sanyo model:

The Fujitsu website can be found at:

For information of the Friedrich line, see:

The Mitsubishi Mr. Slim line is accessible at:

Hope this information is helpful. If you have any questions or if there is anything else I can do to assist, please let me know.


The energy consumption reduction due to the heat pumps that you are experiencing are impressive. Air sourced heat pumps save a lot in capital costs compared to ground-sourced heat pumps, however, they are really challenged when the temperature goes to extremes (with respect to heating, it is where most of the heating demand occurs - moreso than the proportional temperature difference with the outside). The COP numbers that you referred to are for a specific outside temperature and when the temperature drops (or increases in the summer) the COP drops dramatically. Do you know at what temperature that they were tested at?


Hi Retsel,

The HSPF ratings I mention are based on Zone 4 and Halifax, at 7,860 HDD (°F), falls within this band. As I understand it, heat pumps in Canada are certified in accordance to the ARI 210/240-89 and ASHRAE 37-1988 testing standard and for the United States the ARI 310/380-93 standard is used. These standards define a broad range of temperatures and spell out the number of hours of operation at each of the various temperature points within this range, i.e., "bins". This is intended to more accurately reflect "real world" conditions as would be experienced over the course of the entire heating season.

I should note that at -18°C/0°F, my Sanyo provides over half its nominal heating capacity and I can personally attest that at -23°C it still cranks out a good amount of heat. Of course, one of the nice things about inverter systems is that you can install a larger model with greater heating capacity and not worry about poor cooling performance come summer (with non-inverter models, heat pumps are typically undersized with respect to their heating loads simply to ensure good dehumidification).

Addendum: For those living in very cold climates, Mitsubishi offers a line of ductless heat pumps that supply 100 per cent of their nominal heating capacity at -15°C and 87 per cent at -20°C, with up to four hours of continuous heating between defrost cycles.



We heat with wood. We use highly efficient wood burners sometimes called finovens. They are about 90% efficient and produce about 2% of the pollution of standard wood burners (for the same heat production) in Holland they can be found at
in France: We prefer the way they function over that of a standard wood burner, you make a very fast burning wood fire which burns in about 70 minutes. You close them up, and they stay warm for the next 12 - 16 hours. Because they are optimized for good combustion, soft woods can be burned without any problem. I never have to sweep the chimney, just a yearly vacuuming out of ashes and particles which have fallen down the flue. Minimum weight is about 800 Kg (heavier versions can stay warm much longer between fires). Once the fire is out the combustion chamber can also be used for baking.

This said, our insulating budget is currently about 700 euros/year and it looks like it will continue at that rate for the next few years. Our next investment in heating will undoubtedly be trombe walls, passive solar and insulation are the best possible heating.

Cut down all the damned ornamental pear trees and plant some real fruit trees - two birds with one stone.