In his overview of wood as fuel and a source of energy from the Encyclopedia of Forest Sciences, Forest Products Laboratory retiree John Zerbe reviews chips and sawdust, shavings, manufactured fireplace logs, and briquettes as sources of wood energy, but here at FPL, we know that wood pellets are the most popular alternative to cordwood for heating.
Zerbe and FPL Natural Resources Specialist Mark Knaebe state that wood pellets are becoming increasingly popular. Pellets are made from processed, ground, debarked logs held together with a binder. When pellets are made from clean wood with little bark, the ash content is low.
Pellets are sold at retail outlets in 40-pound sacks, which handle and store easily. The consumer can purchase pellets in bulk, including in one-ton bags, which can be replenished by a truck delivery. Knaebe says, “Bulk pellets are just like with oil heat: the truck will come and fill your container, and your thermostat tells an auger to feed your boiler or furnace. The pellets should be kept dry to prevent disintegration and to avoid risk of mold and decay.”
“In very large piles of pellets,” warns Knaebe, “you will get a fire about 3 weeks after the pile gets wet because of spontaneous combustion and the high insulating properties of a big pile. This can be prevented with blowers or making smaller piles, never more than 10 feet deep.”
Sometimes pellets for cooking are made from woods with special flavors that can be used in barbecuing, directly or with charcoal or gas, for conveying this flavoring to meat or poultry. Excellent pellet grills are available now. However, the most common use of pellet fuel is for heating with modern and convenient pellet stoves. Some of these stoves have automatic ignition, feed, and control systems. To be EPA certified, they must be 78% efficient. To determine the efficiency of your fuel, you can download FPL’s popular Fuel Value and Power Calculator.