What are Wood Pellets?
Wood pellets are a form of bio fuel and just one of the numerous types of fuel pellets currently produced in the world today. While other fuel pellets are made from materials such as dried grasses and corn, wood pellets are made various types of wood. By compressing sawdust into pellets, a fuel is created that has benefits in the home, in commercial applications and in the environment. Wood pellets are more efficient than burning cord wood, create far less carbon and have the EPA’s approval. Pellets are considered carbon neutral.
What are fuel pellets made of?
All pellets are biomass materials, products of commonly grown plants and trees. In the past, the most common residential pellets were made from sawdust and ground wood chips, which are waste materials from trees used to make furniture, lumber, and other products. The use of wood is the most bountiful supply source that does not affect the cost of food or ethanol production.
In recent production processes, low-grade forest products such as round pulp and other low-grade woods have been debarked and chip for raw material. Resins and binders occurring naturally in the wood products hold wood pellets together, so they usually contain no additives. Other type of pellets use nut hulls and other materials, and unprocessed shelled corn and fruit pits can be burned in a few pellet stove designs. The choice of fuel and its price may depend on the regional waste biomass most available.
These raw materials are processed under high pressure and temperature and compressed into small pellets, cylindrical in shape. Softwood (e.g. conifers, pines), hardwood (e.g. oak) and clean recycled wood waste may be used to make the product. Wood pellets are manufactured at wood pellet mills or plants.
How are they made?
Pellet mills across the country receive, sort, grind, dry, compress, and bag wood and other biomass waste products used to produce fuel pellets. The manufacturing process is determined by the raw material but usually includes the following steps: reception of raw material, screening, grinding, drying, pelletizing, cooling, sifting, and packaging. As of 2007, over eighty pellet mills across North America produced in excess of 3,400,000 tons of fuel per year. Pellets are usually packaged in forty-pound bags and sold by the bag or by the ton. Pellets are available for purchase at stove dealers, nurseries, building supply stores, feed and garden supply stores, and some discount merchandisers.
Advantages of wood pellets
Convenience. Bags of pellets stack compactly and store easily. A ton of pellets can be stacked in an area as small as four feet wide, long, and high, an area about half the space needed for a cord of wood. Bags of pellets can be stored in a small area of a dry garage, basement, or utility room or shed.
Easy Loading. Loading the hopper is normally required only once a day and may be even less frequent when the stove is used on low settings.
Better Fuel Regulation. The small size of pellets allows for precisely regulated fuel feed. In turn, combustion air can be regulated easily for optimum burn efficiency since the amount of fuel in the burn pot is predictable and consistent.
Fuel Efficiency. High combustion efficiency is also due to the uniformly low moisture content of pellets (consistently below 10% compared to 20 to 60% moisture content in cordwood). Uniformly low moisture, controlled fuel batches, and precisely regulated combustion air means high heat output and a very low level of unwanted emissions.
Sustainable Source. Sustainable energy supplies through renewable forestry materials resources, pellets are a by-product of other forestry manufacturing and lower grade timber products. Using pellets also helps reduce the costs and problems of waste disposal.
Comfort. The combination of fans delivering warm air currents and the direct comfort of radiant heat provides special satisfaction on a cold winter day. The heat provided is even and constant, due to the automatically regulated fuel feed responding to owner settings.
Economics. Fuel pellets are less expensive than other fuels and retain capital in the local economies in which they are manufactured. The ripple effect on the local economies in which wood pellets are produced cross many boundaries.
Wood pellet history
Compared to other fuels in use today, wood pellets, which were introduced in North America in the 1970s as an alternative fuel, can be considered a relatively new type of fuel. Wood pellets’ primary purpose was to help resolve the energy crisis. In the beginning, they were used mainly by industrial, commercial and institutional sectors for heating.
The first residential wood pellet stoves were sold to consumers in 1983. In 2006, North America had over 80 wood pellet manufacturers and produced about 2,300,000 tons of pellets. In comparison for 2006, Europe was the location of more than 300 wood pellets manufacturers with production totaling 4,500,000 tons.