Heating with Wood

By Thembi Borras

The following suggestions are provided to support firewood harvested sustainably, burned cleanly and efficiently, and its energy used.

1. Harvest your firewood sustainably, which includes not cutting wildlife trees, avoiding damage to remaining trees, using existing roads, matching the weather to the surface of the road, selecting trees with the future condition of the stand in mind and where appropriate giving removal preference to hardwoods overtopping or competing with conifers. If you buy your firewood, ask your supplier where the wood came from. Make it known you only want wood harvested sustainably. Also, be aware of diseases which may use your vehicle as a vector, such as Sudden Oak Death.

2. Design your wood burning system such that it burns wood cleanly and efficiently (more on this next week). The efficiency of the wood burning system you select can vary greatly, open fireplaces deliver between zero and 20% net efficiency, whereas the contemporary "hi-tech" air tight wood stove may deliver better than 75% net efficiency.

3. Install your indoor wood burning system per the manufacturer specifications and maintain it so that it remains working efficiently and safe. Maintenance includes cleaning the accumulation of creosote in the chimney, which is a flammable by-product of wood combustion. Most stove-related fires are attributable to installation, operation and maintenance, rather than product defects.

4. Your wood burning system can only operate with high efficiency and low emissions if your firewood is properly seasoned. Properly seasoned firewood has a moisture content of less than 20%. One way to properly season your firewood is to cut, split and stack the wood in the early spring and let it stand in the sun and wind all summer. Symptoms of poor performance related to wet firewood include, difficulty getting a fire going and keeping it burning, smoky fires with little flame, dirty glass, rapid creosote buildup in the chimney, low heat output, the smell of smoke in the house, short burn times, excessive fuel consumption and blue-gray smoke from the chimney.

5. Insulate your home to contain the heat you produce. Note open fireplaces may perform very badly in tight homes because the house is easily depressurized.

For more information, visit the website http://www.co.mendocino.ca.us/aqmd/, from which this production was gleaned. The article "Heating with Wood" by G. Nelson Wolfe was also used as a source.