Firewood is any wooden material that is collected and used for fuel . Generally, firewood is not highly processed and is in some form of recognizable log or branch form, compared to other forms of wood fuel like pellets or chips. Firewood can be seasoned (dry) or unseasoned (fresh / wet). It can be classified as hardwood or softwood .
Firewood is a renewable resource . However, demand for this fuel can be expanded to a local level. Firewood can improve local wood supplies.
Harvesting
Harvesting or collecting firewood by the region and culture. Some places have specific areas for firewood collection. Other places can integrate the collection of firewood in the cycle of preparing a plot of land to grow food as part of a field rotation process. Collection can be a group, family or an individual activity. The tools and methods for harvesting firewood are diverse.
North America
Some firewood is harvested in ” woodlots ” managed for that purpose, [1] but it is more often than not, it is usually harvested by a byproduct of natural forests . Deadfall That Has not started to rot is preferred, since it is already Partly seasoned . Stuck on the trunk is better, it is less likely to be trunk, Harvesting this form of timber reduces the incidence of bushfires , but also reduces habitat for snag-nesting animals such as owls and some rodents.
Harvesting timber for firewood is Normally the carried out by hand with chainsaws . Thus, longer parts – requiring less manual labor, and less chainsaw fuel – are less expensive and only limited by the size of the firebox. In MOST of the United States, the standard measure of firewood is a cord or 128 cubic feet (3.6 m 3 ), HOWEVER, firewood can be sold by weight aussi. The BTU value can affect the price. Also vary with the distance from wood lots, and quality of the wood.
And burning firewood which was cut to a limited distance from its final destination prevents the accidental spread of invasive tree-killing insects and diseases. [2] [3]
Preparing
In most parts of the world, firewood is only prepared for transport at the time it is harvested. Then it is moved closer to the place it will be used as fuel and prepared there. The process of making charcoal from firewood can take up at the place the firewood is harvested.
Most firewood also requires splitting, which also allows for greater seasoning by exposing more surface area. This is a splitting machine, but it can be split with a splitting machine . More unusual, and dangerous, is a tapered screw-style design, that augers into the wood, splitting it, and can be powered by either a power take-off drive, a dedicated internal combustion engine, or a rugged electric pipe-threading machine , which is safer than the other power sources because the power can be shut off more easily if necessary. Another method is a kinetic log splitter, which uses a rack and pinion system powered by a small motor and a large flywheel used for energy storage.
Storing
There are many ways to store firewood. These range from simple batteries to free-standing stacks, to specialized structures. Usually the goal of storing wood is to keep water away from it and to continue the drying process.
Stacks: The simplest stack is one of the following. The height of the stack can vary. Without constructing ends, the length of the log and the length of the stack help determine the height of a free-standing stack.
There is debate about whether wood will dry more quickly when covered. There is a trade-off between the surface of the wood getting wet vs. allowing as much wind and sun as possible to access the stack. A cover can be almost any material that sheds water – a large piece of plywood, sheet metal, terracotta tiles, or an oiled canvas cloth, even cheap plastic sheeting may also be used. Wood will not dry when completely covered. Ideally pallets or scrap wood should be used to raise the ground.
There are many ways to create the ends of a stack. In some areas, the results of this study are as follows: A stake or pole in the ground is another way to the pile. A series of stacked logs at the end, each with a cord tied to it and the free end of the string wrapped in the middle of the stack, is another way.
Under a roof: There is no need for a roof of the roof, but it does not need to be provided. The methods for stacking depend on the structure and layout desired. Whether split, or in ’rounds’ (flush-cut and unsplit segments of logs), the wood should be stacked lengthwise, which is the most stable and practical method. Again though, if there is a need for adequate air flow through the stack.
Storing outdoors: Firewood should be stacked with the bark facing upwards. This allows the water to drain off, and stand up frost, ice, or snow to be kept from the wood.
Round stacks can be made many ways. Some are stacks of wood with a stacked circular wall around them. Others like the Holz Hausen are more complicated.
- A holz hausen, or “wood house”, is a circular method of stacking wood; proponents say it’s going to slow down on a relatively small footprint. A traditional holz hausen has a 10-foot diameter, stands 10 feet high, and holds about 6 cords of wood. The walls are made of pieces arranged radially, and tilted slightly inward for stability. The inside pieces are stacked on a chimney for air flow. The top pieces are slightly straightened out. [4]
Heating value
The moisture content of firewood determines how it burns and how much heat is released. Unseasoned (green) wood moisture content varies by the species; green wood may weigh 70 to 100 percent. Typically, seasoned (dry) wood has 20% to 25% moisture content. Use of the lower heating value is advised [5] as a reasonable standard way of reporting this data.
The energy of a measure of wood depends on the tree species. [6] For example, it can range from 15.5 to 32 million British thermal units (16.4 to 33.8 GJ) per cord. [7] The higher the moisture content, the more energy that must be used to evaporate (boil) the water in the wood before it will burn. Dry wood delivers more energy for the environment.
The Sustainable Energy Development Office (SEDO), part of the Government of Western Australia states that the energy content of wood is 4.5 kWh / kg or 16.2 gigajoules / ton (GJ / t). [8]
Here are some examples of energy content of several species of wood:
Wood Species | Heat Value per Cord |
---|---|
Tamarack | 22.3 MMBtu (23.5 GJ ) |
Birch | 21.3 MMBtu (22.5 GJ) |
Red Fir | 20.6 MMBtu (21.7 GJ) |
White Fir | 16.7 MMBtu (17.6 GJ) |
Kiln dried firewood
The process of kiln drying firewood was invented by Anthony Cutara, for which a successful US patent was filed in 1983. [9] In 1987 the US Department of Agriculture has published a detailed procedure for the production of kiln dried firewood, citing the higher heat output and increased combustion efficiency as a key benefit of the process [10]
Measurement
Usually firewood is sold by volume. While a specific volume may be used, there can be a wide variation in what this means and what can measure produce a fuel. For example, a string that is made from 4-foot (1.22 m) logs, which will be cut through a 3-inch (7.6 cm) circle. A measure of green unseasoned wood with 65% moisture contains less than 20% of the energy. Regardless of the term, firewood measurement is best thought of as an estimate.
Metric
In the metric system , firewood is usually sold by the stere , equivalent to a volume of 1 cubic meter (1 cubic meter or 0.276 cords). The most common firewood piece length is 33 cm and 50 cm. Wood can also be sold by the metric tons , as in Australia .
North America
In the United States and Canada , face cord or bag.
- A full cord or bush cord : has a volume of 128 cubic feet (3.6 m 3 ), Including wood, bark, and air space in a neatly stacked pile. [11] The actual wood volume of a cord may be in the range of 80 to 100 cubic feet (2.3 to 2.8 m 3 ) as a piece of solid wood. The most common firewood piece is 16 inches (41 cm). [12]
- A face cord is one third of a full gold bush string stack of wood that is 4 by 8 ft (1.22 by 2.44 m) by 16 in (41 cm) and has a volume of 42.6 cubic feet (1.21 m 3 ). [12]
In popular culture
In Norway , the non-fiction book Hel Ved (English: Solid Wood: All About Chopping, Drying and Stacking Wood – and the Soul of Wood-Burning ) by Lars Mytting became a bestseller in 2011/2012, selling 150,000 copies. A version of the book has been published in Sweden , selling 50,000 copies. [13]
In February 2013, the Norwegian state broadcast NRK has a 12-hour live program on the topic of woodfire, where a large part of the program of firewood burning in a fireplace. More than one million people, 20% of Norway’s population, part of the program. [14]
See also
- Biomass
- Cordwood construction
- Multipurpose tree
- Wood ash
References
- Jump up^ “Where does firewood come from?” .
- Jump up^ “Do not Move Firewood – Trees and forests are threatened by invasive foreign insects and diseases” . dontmovefirewood.org .
- Jump up^ “Firewood” . www.inspection.gc.ca . Government of Canada, Plant Health and Biosecurity Directorate, Canadian Food Inspection Agency.
- Jump up^ “Seasoning Firewood How and When” . thechimneysweep.ca .
- Jump up^ “Firewood Storage Racks – Wood Covers” . Firewood Rack . Retrieved 2010-07-29 .
- Jump up^ “Northidahofirewood.com” . northidahofirewood.com . Archived from the original on 2009-02-06.
- Jump up^ John Gulland. “A non-commercial service in support of responsible home heating with wood – Firewood” . woodheat.org .
- Jump up^ “Office of Energy – Clean Energy” . Sedo.energy.wa.gov.au. 2010-01-01. Archived from the original on October 13, 2009 . Retrieved 2010-07-29 .
- Jump up^ “Packaged kiln dried firewood” .
- Jump up^ Simpson, William T .; Boone, R. Sidney; Chern, Joseph; Mace, Terry (August 1987). “Kiln-Drying Time of Oak Firewood Split” (PDF) . Madison, WI: US Department of Agriculture, Forest Service, Forest Products Laboratory.
- Jump up^ “Buying Firewood? Do not Get Burned!” . Measurement Canada. Retrieved 2013-08-15.
- ^ Jump up to:a b “What’s a Cord? And How to Avoid Paying Too Much for One” . Woodheat.org. Retrieved 2013-08-16.
- Jump up^ Norsk ved-TV vekker oppsikt i USAAftenposten, February 20, 2013
- Jump up^ Sarah Lyall:Bark Up or Down? Firewood Splits Norwegians New York Times, February 19, 2013