Alternative fuels, known as non-conventional or advanced fuel

Fuel

Fuel is any material that stores energy that can later be extracted to perform mechanical work in a controlled manner. Most fuels used by humans undergo combustion, a redox reaction in which a combustible substance releases energy after it ignites and reacts with the oxygen in the air...

s, are any material

Material

Material is anything made of matter, constituted of one or more substances. Wood, cement, hydrogen, air and water are all examples of materials. Sometimes the term "material" is used more narrowly to refer to substances or components with certain physical properties that are used as inputs to...

s or substance

Chemical substance

In chemistry, a chemical substance is a form of matter that has constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e. without breaking chemical bonds. They can be solids, liquids or gases.Chemical substances are...

s that can be used as fuel

Fuel

Fuel is any material that stores energy that can later be extracted to perform mechanical work in a controlled manner. Most fuels used by humans undergo combustion, a redox reaction in which a combustible substance releases energy after it ignites and reacts with the oxygen in the air...

s, other than conventional fuels. Conventional fuels include: fossil fuels (petroleum

Petroleum

Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...

 (oil), coal

Coal

Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

, propane

Propane

Propane is a three-carbon alkane with the molecular formula , normally a gas, but compressible to a transportable liquid. A by-product of natural gas processing and petroleum refining, it is commonly used as a fuel for engines, oxy-gas torches, barbecues, portable stoves, and residential central...

, and natural gas

Natural gas

Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...

), as well as nuclear materials such as uranium

Uranium

Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...

 and thorium

Thorium

Thorium is a natural radioactive chemical element with the symbol Th and atomic number 90. It was discovered in 1828 and named after Thor, the Norse god of thunder....

, as well as artificial radioisotope fuels that are made in nuclear reactors, and store their energy.

Some well-known alternative fuel

Fuel

Fuel is any material that stores energy that can later be extracted to perform mechanical work in a controlled manner. Most fuels used by humans undergo combustion, a redox reaction in which a combustible substance releases energy after it ignites and reacts with the oxygen in the air...

s include biodiesel

Biodiesel

Biodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl esters. Biodiesel is typically made by chemically reacting lipids with an alcohol....

, bioalcohol (methanol

Methanol

Methanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH . It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol...

, ethanol

Ethanol

Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...

, butanol

N-Butanol

n-Butanol or n-butyl alcohol or normal butanol is a primary alcohol with a 4-carbon structure and the molecular formula C4H9OH. Its isomers include isobutanol, 2-butanol, and tert-butanol...

), chemically stored electricity

Electricity

Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...

 (batteries and fuel cell

Fuel cell

A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used...

s), hydrogen

Hydrogen

Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

, non-fossil methane

Methane

Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...

, non-fossil natural gas

Natural gas

Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...

, vegetable oil

Vegetable oil used as fuel

Vegetable oil is an alternative fuel for diesel engines and for heating oil burners. For engines designed to burn diesel fuel, the viscosity of vegetable oil must be lowered to allow for proper atomization of the fuel, otherwise incomplete combustion and carbon build up will ultimately damage the...

, and other biomass

Biomass

Biomass, as a renewable energy source, is biological material from living, or recently living organisms. As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel....

 sources.

Background

The main purpose of fuel is to store energy, which should be in a stable form and can be easily transported to the place of production. Almost all fuels are chemical fuels. The user employs this fuel to generate heat or perform mechanical work, such as powering an engine. It may also be used to generate electricity, which is then used for heating, lighting or electronics purposes.

Biofuel

Biofuels are also considered a renewable source. Although renewable energy is used mostly to generate electricity, it is often assumed that some form of renewable energy or at least it is used to create alternative fuels.

Biomass

Biomass in the energy production industry is living and recently dead biological material

Biological material

Biological material may refer to:* Tissue , or just tissue* Biomass, living or dead biological matter, often plants grown as fuel* Biomass , the total mass of living biological matter* Biomaterials...

 which can be used as fuel or for industrial production.

Algae based fuels

Algae based biofuels have been hyped in the media as a potential panacea to our Crude Oil based Transportation problems. Algae could yield more than 2000 gallons of fuel per acre per year of production. Algae based fuels are being successfully tested by the U.S. Navy Algae based plastics show potential to reduce waste and the cost per pound of algae plastic is expected to be cheaper than traditional plastic prices.

Alcohol fuels

Methanol and Ethanol fuel are typically a primary sources of energy; they are convenient fuels for storing and transporting energy. These alcohols can be used in "internal combustion engines as alternative fuels", with butanol also having known advantages, such as being the only alcohol-based motor fuel that can be transported readily by existing petroleum-product pipeline networks, instead of only by tanker trucks and railroad cars.

Ammonia

Ammonia

Ammonia

Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...

 can be used as fuel. A small machine can be set up to create the fuel and it is used where it is made. Benefits of ammonia include, no need for oil, zero emissions, low cost, and distributed production reducing transport and related pollution.

Hydrogen

Hydrogen is an emissionless fuel. The byproduct of hydrogen burning is water, although some mono-nitrogen oxides NOx

NOx

NOx is a generic term for the mono-nitrogen oxides NO and NO2 . They are produced from the reaction of nitrogen and oxygen gases in the air during combustion, especially at high temperatures...

 are produced when hydrogen is burned with air.

HCNG

HCNG

HCNG

HCNG is a mixture of compressed natural gas and 4–9 percent hydrogen by energy. It may be used as a fuel gas for internal combustion engines and home appliances...

 (or H2CNG) is a mixture of compressed natural gas

Compressed natural gas

Compressed natural gas is a fossil fuel substitute for gasoline , diesel, or propane/LPG. Although its combustion does produce greenhouse gases, it is a more environmentally clean alternative to those fuels, and it is much safer than other fuels in the event of a spill...

 and 4-9 percent hydrogen

Hydrogen

Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

 by energy.

Liquid nitrogen

Liquid nitrogen

Liquid nitrogen vehicle

A liquid nitrogen vehicle is powered by liquid nitrogen, which is stored in a tank. The engine works by heating the liquid nitrogen in a heat exchanger, extracting heat from the ambient air and using the resulting pressurized gas to operate a piston or rotary engine...

 is another type of emissionless fuel.

Compressed air

The air engine is an emission-free piston engine using compressed air as fuel. Unlike hydrogen, compressed air is about one-tenth as expensive as fossil oil, making it an economically attractive alternative fuel.

Alternative fossil fuels

Compressed natural gas

Compressed natural gas

Compressed natural gas is a fossil fuel substitute for gasoline , diesel, or propane/LPG. Although its combustion does produce greenhouse gases, it is a more environmentally clean alternative to those fuels, and it is much safer than other fuels in the event of a spill...

 (CNG) is a cleaner burning alternative to conventional petroleum automobile

Automobile

An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...

 fuels. The energy efficiency is generally equal to that of gasoline engines, but lower compared with modern diesel engines. CNG vehicles require a greater amount of space for fuel storage than conventional gasoline power vehicles because CNG takes up more space for each GGE (Gallon of Gas Equivalent). Almost any existing gasoline car can be turned into a bi-fuel (gasoline/CNG) car. However, natural gas is a finite resource like all fossil fuels, and production of natural gas is expected to peak soon after oil.

Nuclear reactors

Nuclear power is any nuclear technology

Nuclear technology

Nuclear technology is technology that involves the reactions of atomic nuclei. Among the notable nuclear technologies are nuclear power, nuclear medicine, and nuclear weapons...

 designed to extract usable energy from atomic nuclei via controlled nuclear reactions. The only controlled method now practical uses nuclear fission

Nuclear fission

In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the nucleus of an atom splits into smaller parts , often producing free neutrons and photons , and releasing a tremendous amount of energy...

 in a fissile

Fissile

In nuclear engineering, a fissile material is one that is capable of sustaining a chain reaction of nuclear fission. By definition, fissile materials can sustain a chain reaction with neutrons of any energy. The predominant neutron energy may be typified by either slow neutrons or fast neutrons...

 fuel (with a small fraction of the power coming from subsequent radioactive decay

Radioactive decay

Radioactive decay is the process by which an atomic nucleus of an unstable atom loses energy by emitting ionizing particles . The emission is spontaneous, in that the atom decays without any physical interaction with another particle from outside the atom...

). Use of the nuclear reaction nuclear fusion

Nuclear fusion

Nuclear fusion is the process by which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus. This is usually accompanied by the release or absorption of large quantities of energy...

 for controlled power generation is not yet practical, but is an active area of research.

Nuclear power is usually used by using a nuclear reactor

Nuclear reactor

A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...

 to heat a working fluid such as water, which is then used to create steam pressure, which is converted into mechanical work for the purpose of generating electricity or propulsion in water. Today, more than 15% of the world's electricity comes from nuclear power, and over 150 nuclear-powered naval vessels have been built.

In theory, electricity from nuclear reactors could also be used for propulsion

Nuclear propulsion

Nuclear propulsion includes a wide variety of propulsion methods that fulfil the promise of the Atomic Age by using some form of nuclear reaction as their primary power source.- Surface ships and submarines :...

 in space, but this has yet to be demonstrated in a space flight. Some smaller reactors, such as the TOPAZ nuclear reactor

Topaz Nuclear Reactor

The TOPAZ nuclear reactor is a lightweight nuclear reactor developed for long term space use by the Soviet Union. Cooled by liquid metal, it uses a high-temperature moderator containing hydrogen and highly enriched fuel and produces electricity using a thermionic converter.-Nomenclature:In initial...

, are built to minimize moving parts, and use methods that convert nuclear energy to electricity more directly, making them useful for space missions, but this electricity has historically been used for other purposes. Power from nuclear fission

Nuclear fission

In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the nucleus of an atom splits into smaller parts , often producing free neutrons and photons , and releasing a tremendous amount of energy...

 has been used in a number of spacecraft, all of them unmanned. The Soviets up to 1988 orbited 33 nuclear reactors in RORSAT

RORSAT

Radar Ocean Reconnaissance SATellite or RORSAT is the western name given to the Soviet Upravlyaemyj Sputnik Aktivnyj satellites. These satellites were launched between 1967 and 1988 to monitor NATO and merchant vessels using active radar...

 military radar satellites, where electric power generated was used to power a radar unit that located ships on the Earth's oceans. The U.S. also orbited one experimental nuclear reactor in 1965, in the SNAP-10A

SNAP-10A

SNAP-10A was the first and so far only known launch of a U.S. nuclear reactor into space . The Systems Nuclear Auxiliary Power Program reactor was developed under the SNAPSHOT program overseen by the U.S...

 mission. No nuclear reactor has been sent into space since 1988.

Radiothermal generators

In addition, radioisotopes have been used as alternative fuels, on both land and in space. Their use on land is declining due to the danger of theft of isotope and environmental damage if the unit is opened. The decay of radioisotopes generates both heat and electricity in many space probes, particularly probes to outer planets where sunlight is weak, and low temperatures is a problem. Radiothermal generators (RTGs) which use such radioisotopes as fuels do not sustain a nuclear chain reaction, but rather generate electricity from the decay of a radioisotope which has (in turn) been produced on Earth as a concentrated power source (fuel) using energy from an Earth-based nuclear reactor

Nuclear reactor

A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...

.

See also

• Alternative fuel cars
• Alternative propulsion
• Greasestock
  Greasestock
  Greasestock is an American event held yearly in Yorktown Heights, New York. It is one of the largest alternative fuel, renewable energy, and low-energy green vehicle exhibitions in the United States. Exhibitors showcase a variety of alternative energy vehicles, as well as exhibits with a...
  
   - An alternative fuel festival in New York
• List of 2007 Hybrid Vehicles
• Alcohol fuel
  Alcohol fuel
  Although fossil fuels have become the dominant energy resource for the modern world, alcohol has been used as a fuel throughout history. The first four aliphatic alcohols are of interest as fuels because they can be synthesized chemically or biologically, and they have characteristics which allow...
  
  
• Biogas
  Biogas
  Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal dung, and kitchen waste can be converted into a gaseous fuel called biogas...
  
  
• Compressed-air vehicle
  Compressed-air vehicle
  A compressed-air vehicle is powered by an air engine, using compressed air, which is stored in a tank. Instead of mixing fuel with air and burning it in the engine to drive pistons with hot expanding gases, compressed-air vehicles use the expansion of compressed air to drive their pistons...
  
  
• Magnesium injection cycle
  Magnesium injection cycle
  Magnesium Injection Cycle is an engine design currently under development by Mitsubishi Corporation and the Tokyo Institute of Technology which uses magnesium and water to generate power...
  
  
• NGH - A possible future alternative to LNG for transporting natural gas
  Natural gas
  Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
  
  
• Vegetable oil used as fuel
  Vegetable oil used as fuel
  Vegetable oil is an alternative fuel for diesel engines and for heating oil burners. For engines designed to burn diesel fuel, the viscosity of vegetable oil must be lowered to allow for proper atomization of the fuel, otherwise incomplete combustion and carbon build up will ultimately damage the...
  
  
• Swiftfuel -- A potential lead-free alternative to 100LL aviation gasoline.
• Energy development
  Energy development
  Energy development is the effort to provide sufficient primary energy sources and secondary energy forms for supply, cost, impact on air pollution and water pollution, mitigation of climate change with renewable energy....
  
  
• List of energy topics
• Heating value

External links

• Alternative Fuels Data Center (U.S. DOE)
• Alternative Fuels Information Centre (Victorian Government)
• Alternative Fuel Vehicle Training National Alternative Fuels Training Consortium, West Virginia University
• Clean Cities Program U.S. DOE program encouraging alternative fuel use
• International Air Transport Association alternative aviation fuels
• ScienceDaily - Alternative Fuel News
• http://www.energyquest.ca.gov/transportation/electric.htmlStudent's Guide to Alternative Fuel (California Energy Commission
  California Energy Commission
  The California Energy Commission is California’s primary energy policy and planning agency. Created in 1974 and headquartered in Sacramento, the Commission has responsibility for activities that include forecasting future energy needs, promoting energy efficiency through appliance and building...
  
  )]
• Sustainable Green Fleets, an EU-sponsored dissemination project for alternatively fuels for fleets
• Pop. Mechanics: Crunching the numbers on alternative fuels
• Global list of Alternative Fuels related Organizations on WiserEarth
• Alternative Fuels portal on WiserEarth