1. Definitions

Webster’s Revised Unabridged Dictionary: A substance of vegetable origin, consisting of roots and fibres, moss, etc., in various stages of decomposition, and found, as a kind of turf or bog, usually in low situations, where it is always more or less saturated with water. It is often dried and used for fuel. Peat bog, a bog containing peat; also, peat as it occurs in such places; peat moss. — Peat moss. (a) The plants which, when decomposed, become peat. (b) A fen producing peat. (c) (Bot.) Moss of the genus Sphagnum, which often grows abundantly in boggy or peaty places. — Peat reek, the reek or smoke of peat; hence, also, the peculiar flavour given to whisky by being distilled with peat as fuel. [1]

Academic Press Dictionary of Science Technology: A dark-brown or black mass of unconsolidated, semicarbonised, partially decomposed plant debris formed in an anaerobic, water-saturated environment, such as a marsh or bog. It is commonly used as fertilizer and is used as a fuel. [2]

Europe Information Service: It is the partially decomposed remains of plants, which have accumulated, in a waterlogged environment. It is harvested from the surface and air-dried. It contains high amounts of carbon, so the combustion of peat, while low in SOx and NOx, has high carbon emissions – something like 20% higher as coal at the same efficiency level. Release of this carbon can, however, be countered by the re-creation of carbon sinks on lands where the peat has been cut away. It comes from the carbon cycle in the biosphere. Although energy peat releases CO2 during combustion, forming peat bogs are effectively a carbon sink. [3]

[GLOSS]Peat[/GLOSS] is a complex material consisting of plant fibres that contain hemicellulose, cellulose, humic acids, fulvic acids, bitumens, waxes, resins, ash, and readily and nonreadily hydrolysable substances. These constituents in peat, especially lignin, contain polar functional groups such as alcohol, aldehydes, ketones, phenolic hydroxides, and ethers that can be involved in chemical bonding. Because of the polar character of some of the peat constituents, it has good applicability for specific sorption of dissolved solids, such as transition metals and polar organic molecules such as ammonia. In addition, peat has ion exchange properties because of the presence of humic acids. Peat is one of the few materials that behave like activated carbon, in that it adsorbs organics and also is similar to ion exchange resins, which adsorb a variety of substances such as heavy metals.

Peat energy offers a good number of solutions for power generation, more particularly for combined heat and power (CHP). Because of peat’s poor energy density – and high water content – transport of peat for energy is limited to 100 kilometres from the production areas. It makes peat an indigenous fuel, i.e. produced and consumed locally, contributing to job creation in some very under-developed regions. [4]

2. Fossil, Renewable or Biomass?

All the major international agencies (IPCC, IEA, UNESCO and WWF) categorise peat as a fossil source of energy ([GLOSS]fossil fuel[/GLOSS]), because it cannot be renewed within any reasonable economic time frame, having accumulated over thousands of years. [5]

The European Biomass Association indicates in several articles that peat belongs to the biomass: “Kinds of biomass used are peat, wood, wood waste, black liquor and industrial and municipal waste.” [6]

Also, the European Union defines the peat as a type of coal: “Currently renewable energy, such as solar or wind power, accounts for six percent of the European Union’s energy needs. Some 41 percent is covered by oil, 22 percent by gas, 16 percent by coal (hard coal, lignite and peat) and 15 percent by nuclear.” [7]

3. Formation of Peat Bogs

Many peat bogs at one time were small lakes and ponds. In one type of bog formation, vegetation that started growing near the water’s edge, gradually spread to deeper water. After centuries, some of these water bodies became completely filled with vegetation and began to grow both upward and outward until large expanses of adjacent wetlands were covered. As the peat accumulates, the water level rises and the bog remains saturated, except for a few inches on the top, where new growth occurs. Bog vegetation includes mosses, reed sedges, grasses, shrubs, and even trees. Peat is gradually formed as the vegetation decomposes. Peat can be described as a partially fossilized plant matter that occurs in wetlands where there is a deficiency in oxygen and where the accumulation of plant matter is faster than its decomposition. [4]

Approximately 1.5 percent of the earth’s surface is covered with peat, with the largest deposits occurring in the northern parts of the Northern Hemisphere. Canada and the countries of the former USSR account for approximately 80 percent of the total. Furthermore the United States, Ireland, Finland, Sweden and the tropical country Indonesia have large peat deposits as well (author). Peat, therefore, is an abundant material that is widely available and relatively easy to obtain. [4]

Keywords:

Fossil fuel, fuel, peat, turf

Abbreviations:

IEA International Energy Agency
IPCC Irish Peatland Conservation Council
WWF World Wildlife Found

Source:

[1] Webster’s Revised Unabridged Dictionary
[2] Academic Press Dictionary of Science Technology, http://www.harcourt.com/dictionary/
[3] Europe Information Service, http://www.lgib.gov.uk/eis/index.htm
[4] Peat Technologies Corporation. http://www.peatec.com/background.htm
[5] WWF Climate Change Campaign, Giulio Volpi: PEAT EXTRACTION AND SUSTAINABILITY How peat extraction for energy use increases climate pollution and causes loss of biodiversity.
[6] European Biomass Association. http://www.ecop.ucl.ac.be/aebiom/
[7] Europe Tackles High Cost of Energy Dependency © Environment News Service (ENS) 2001, April 25, 2001
[8] ExternE – Externalities of Energy. A research project of the European Commission. http://externe.jrc.es/da44file3.htm