Heating With Wood



Background

I've always enjoyed the warmth of a fire on a cold evening, but not until we moved to our current house was I able to consider using wood as a primary heat source. The idea appealed to me for a couple of reasons. First, I enjoy doing things for myself and being somewhat self-sufficient, and second, we have enough wooded acreage to support such an endeavor. Since the design of our house is such that a centrally located woodstove is able to heat the entire structure and there was already a woodstove here when we bought the house, it seemed like a natural time to give it a try. We do have an electric heat pump as a backup source of heat should it be needed.


What Wood To Burn?

After I made the decision to heat with wood, my first course of action was a visit to the local library to find references on good forestry practices and using wood as a heat source. My initial interest was in the heating properties of various woods and what woods, specifically, were suitable for burning. I found several lists purporting to categorize the btu values of wood, but few of them agreed with one another. For instance, only one even mentioned Black Locust, the hottest burning hardwood readily available in this area.

What I discovered is that most all wood contains the same BTU per pound.- approximately 8500 - but some woods are more dense than others. Oak, Hickory and Locust are three of the densest available in this area and I have Oak and Locust on my land. My goal is to burn what I have available, but I only use softwoods (conifers) for kindling as they tend to produce more creosote than the hardwoods. Since I only have a handful of fir trees on my property, this isn't a difficult mixture to maintain.


Heating Properties of Various Woods

The culmination of my research was in the following list of heating properties. I believe they are the best measure to use when rating wood for its heating potential.

  1. Hickory, Hop hornbeam (Ironwood), Black Locust, White Oak, and Apple are equal to 0.9 tons of coal, 146 gallons of fuel oil, 174 therms of natural gas, and 3,800 KWH of electricity.
  2. Beech, Sugar Maple, Red Oak, Yellow Birch, and White Ash are equal to 0.8 tons of coal, 133 gallons of fuel oil, 160 therms of natural gas, and 3,500 KWH of electricity.
  3. Gray and Paper Birch, Black Walnut, Black Cherry, Red Maple, Tamarack (Larch), and Pitch Pine are equal to 0.7 tons of coal, 114 gallons of fuel oil, 136 therms of natural gas, and 3,000 KWH of electricity.
  4. American Elm, Black and Green Ash, Sweet Gum, Silver and Bigleaf Maple, Red Cedar, and Red Pine are equal to 0.6 tons of coal, 103 gallons of fuel oil,123 therms of natural gas, and 2,700 KWH of electricity.
  5. Poplar, Cottonwood, Black Willow, Aspen, Butternut, Hemlock, and Spruce are equal to 0.5 tons of coal, 86 gallons of fuel oil, 102 therms of natural gas, and 2,200 KWH of electricity.
  6. Basswood, White Pine, Balsam Fir, and White Cedar are equal to 0.4 tons of coal, 73 gallons of fuel oil, 87 therms of natural gas, and 1,900 KLWH of electricity.

The Woodlot

Many of the books covering heating with wood give various methods for obtaining the fuel. I even ran across one which had an entire chapter devoted to "urban wood gathering". Fortunately, I have my own woodlot so I'll leave it to others to describe how they obtain their wood in a city.

I have almost eleven acres of mixed hardwoods. There are several types of Oak, Black Cherry, Silver Maple, White Ash, Yellow Birch. Black Locust, Dogwood, Tulip Poplar, Black Walnut, Beech, Butternut, Redbud, and a couple of others I won't be able to identify until I have a chance to study their leaves. A book I've found invaluable for tree identification is A Field Guide to Eastern Trees : Eastern United States and Canada.

Conventional wisdom has it that you can sustain a harvest of one cord per year per acre. This is by using everything available to you: downed limbs, storm-downed trees, and by the judicious culling of trees. If you are unwilling to make use of everything, 1/2 cord per acre is a more reasonable measure. We burn approximately 5 cords per year, so the acreage we have should sustain us nicely.


Good Forestry Practices

I am of the belief that we are merely caretakers of the land. I don't get all metaphysical about the philosophy, it just seems to me that since the land will be here long after we're gone, it makes good sense to take care of it in such a way so as to pass it on in better shape than when we took possession of it. If, indeed, one can possess land - it occurs to me that the land possesses us.

I've done some research into good forestry practices and I have much to learn. I'm considering taking some courses from the University of West Virginia which has a notable Forestry Department. I also plan to have the county forestry agent out to look at my land to make suggestions on how I might better it. I just want to improve the forest by good practices, I don't plan to sell timber although I may harvest some of the Oaks and Walnuts for my custom furniture business.


Woodstoves

The woodstove we have is nothing special, it came with the house. It does a good job of heating, but looks a bit too industrial for Petra's tastes and we will soon replace it with a more efficient model which has a larger viewing window. When that time comes, I will move the present stove into my shop which is currently heated by propane.

The design of our house and its location on the building site is ideal for heating purposes. During a winter day, the sun warms the house to almost 80 degrees on many days and the only time I have to fire up the stove is on getting up in the morning and after 5:00 in the evening. I generally load it twice in the evening, with the second load going in about 1:00am. I close the damper about half-way after that loading and the house is kept warm for the rest of the night and there is a good bed of coals left at 10:00 the next morning (yes, I do keep odd hours). On cloudy days, I keep it going all day because there is no heat-gain from the sun.


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