Editing Solid fuel (section)

==Types ==

===Biomass===

Biomass that is used for energy production can be processed into solid fuels but also into liquid or gaseous fuels.<ref name=":3">{{Cite book |url=https://www.worldcat.org/oclc/1137604985 |title=Future energy : improved, sustainable and clean options for our planet |date=2020 |others=T. M. Letcher |isbn=978-0-08-102887-2 |edition=3rd |location=Amsterdam, Netherlands |chapter=Chapter 9: Biofuels for transport |oclc=1137604985}}</ref>{{rp|173}} In comparison, the term [[biofuel]] is nowadays mainly (but not exclusively) used for ''liquid'' or ''gaseous'' fuels, used for transportation.<ref name=":4">The EIA states: "Biofuels are transportation fuels such as ethanol and biodiesel that are made from biomass materials." https://www.eia.gov/energyexplained/index.php?page=biofuel_home</ref>

[[Pellet fuel]]s are made from compressed organic matter or biomass.<ref>{{cite web |title=Biomass Energy |url=http://www.altenergy.org/renewables/biomass.html/ |access-date=16 February 2015 |publisher=Alternate Energy}}</ref> Pellets can be made from any one of five general categories of biomass: industrial waste and co-products, [[food waste]], [[Crop residue|agricultural residues]], [[energy crop]]s, and [[Wood preservation#Chemical|untreated lumber]].<ref>{{cite web |title=Sources of biomass |url=http://www.biomassenergycentre.org.uk/portal/page?_pageid=75,15174&_dad=portal&_schema=PORTAL |url-status=dead |archive-url=https://web.archive.org/web/20160611193224/http://www.biomassenergycentre.org.uk/portal/page?_pageid=75,15174&_dad=portal&_schema=PORTAL |archive-date=11 June 2016 |access-date=16 February 2015 |publisher=BIOMASS Energy Centre}}</ref> Wood pellets are the most common type of pellet fuel.<ref>{{Cite web |date=October 17, 2018 |title=About the Densified Biomass Fuel Report |url=https://www.eia.gov/biofuels/biomass/#about |access-date=October 23, 2018 |website=U.S. EIA}}</ref>{{excerpt|biomass (energy)|paragraphs=1|file=no}}

==== Wood ====
{{Further|Wood fuel}}
Wood fuel can refer to several fuels such as [[firewood]], [[charcoal]], ''wood chips'' sheets, [[Wood pellets|pellets]], and [[sawdust]]. The particular form used depends upon factors such as source, quantity, quality and application. In many areas, wood is the most easily available form of fuel, requiring no [[tool]]s in the case of picking up dead wood, or few tools. Today, [[Combustion|burning]] of wood is the largest use of [[energy]] derived from a solid fuel [[biomass]]. Wood fuel can be used for [[cooking]] and [[heating]], and occasionally for fueling [[steam engine]]s and steam [[turbines]] that [[Electricity generation|generate electricity]]. Wood may be used indoors in a furnace, [[Wood-burning stove|stove]], or [[fireplace]], or outdoors in a furnace, [[campfire]], or [[bonfire]]. As with any [[fire]], burning wood fuel creates numerous by-products, some of which may be useful (heat and steam), and others that are undesirable, irritating or dangerous.

When harvested in a [[sustainable fashion]] wood is usually considered to be a renewable solid fuel ([[renewable energy]]).<ref name="soliftec.com">{{cite web |date=9 February 2014 |title=Solid Fuels |url=http://www.soliftec.com/solidfuels.htm |archive-url=https://web.archive.org/web/20111016185516/http://www.soliftec.com/solidfuels.htm |url-status=usurped |archive-date=October 16, 2011 |access-date=22 June 2015 |publisher=Solid Fuel Technology Institute}}</ref>

There is debate as to whether burning wood can be considered carbon neutral, as technically the wood cannot release more carbon than was sequestered during its growth, although this does not take account of other impacts such as deforestation and rotting has on the [[carbon footprint]].<ref>{{Cite journal |last1=Smith |first1=K.R. |year=1993 |title=Greenhouse gases from biomass and fossil fuel stoves in developing countries: A Manila pilot study |journal=Chemosphere |language=en |volume=26 |issue=1–4 |pages=479–505 |bibcode=1993Chmsp..26..479S |citeseerx=10.1.1.558.9180 |doi=10.1016/0045-6535(93)90440-G}}</ref>

==== Peat ====
{{Further|Peat}}
Peat fuel is an accumulation of partially [[Decomposition|decayed]] [[vegetation]] or organic matter that can be burnt once sufficiently dried. It is used widely in the country districts of [[Ireland]] and [[Scotland]] where alternatives are absent or expensive.{{Citation needed|date=January 2023}} It has a relatively low [[calorific value]], even after essential drying.

===Fossil fuels===

==== Coal ====
{{Further|Coal}}
Coal is a [[combustible]] black or brownish-black [[sedimentary rock]] usually occurring in [[Stratum|rock strata]] in layers or veins called coal beds or coal seams. Throughout history, coal has been used as an energy resource, primarily burned for the production of electricity and heat, and is also used for industrial purposes, such as refining metals. Coal is the largest source of energy for the [[Electricity generation|generation of electricity]] worldwide, as well as one of the largest worldwide  The extraction of coal, its use in energy production and its byproducts are all associated with [[Environmental impact of the coal industry|environmental]] and [[Coal worker's pneumoconiosis|health effects]]. Variations such as smokeless coal can be formed naturally in the form of [[anthracite]], a [[metamorphosed]] type of coal with a very high carbon content that gives off a smokeless flame when set alight. It  is an important type of [[smokeless fuel]].

==== Coke ====
{{Further|Coke (fuel)}}
Coke is a fuel with few impurities and a high [[carbon]] content, usually made from [[coal]]. It is the solid [[carbon]]aceous material derived from [[destructive distillation]] of low-ash, low-sulfur [[bituminous coal]]. Cokes made from coal are grey, hard, and [[porous]]. While coke can be formed naturally, the commonly used form is man-made. The form known as [[petroleum coke]], or pet coke, is derived from oil refinery coker units or other cracking processes.<ref name="soliftec.com" />

==== Smokeless fuel ====
{{Further|Smokeless fuel}}
Solid fuels which produce little smoke or volatiles are made from powdered [[anthracite]] coal and supplied in the form of [[briquettes]] usually for domestic use either in [[stove]]s or open fireplaces. The fuel is replacing coal as a fuel for open fires because of the reduction in particulate emissions and its increased efficiency. Smokeless fuel burns at a higher temperature and more slowly than a coal fire. The term also includes [[charcoal]], made by restricted combustion of dry wood and widely used at open air [[barbecue]]s to cook food on an open fire.

===Solid fuels for special applications===

==== Rocket propellant ====
{{Further|Rocket propellant#Solid chemical propellants}}
Solid rocket propellant consists of a solid oxidizer (such as [[ammonium nitrate]]) bound with flakes or powders of energy compounds (such as [[RDX]]) plus binders, plasticizers, stabilizers, and other additives. Solid propellant is much easier to store and handle than liquid propellant. It also has a higher energy density so it does not require as large of a space for the same amount of stored energy.