Chemicals added to fuel in very small quantities to improve and maintain fuel quality. Detergents, corrosion inhibitors and lubricants are examples of fuel additives.
Broad term that applies to any change after the original purchase, such as adding equipment. When applied to AFVs, it refers to conversion devices or kits for conventional fuel vehicles.
Toxic air pollutants defined under Title II of the CAA, including benzene, formaldehyde, acetaldehyde, 1-3 butadiene, and polycyclic organic matter (POM). Benzene is a constituent of motor vehicle exhaust, evaporative, and fueling emissions. The other compounds are exhaust pollutants.
Organic compounds that are distinguished from hydrocarbons by the inclusion of a hydroxyl group. The two simplest alcohols are methanol and ethanol.
A class of organic compounds derived by removing the hydrogen atoms from an alcohol. Aldehydes can be produced from the oxidation of an alcohol.
Methanol, denatured ethanol, and other alcohols; mixtures containing 85% or more by volume of methanol, denatured ethanol, and other alcohols with gasoline or other fuels; natural gas; liquefied petroleum gas; hydrogen; coal-derived liquid fuels; non-alcohol fuels (such as biodiesel) derived from biological material; and electricity. 'P-Series' fuels were added to this list since the original definition in EPAct.
Alternative Fuel Provider
A fuel provider (or any affiliate or business unit under its control) is an alternative fuel provider if its principal business is producing, storing, refining, processing, transporting, distributing, importing, or selling (at wholesale or retail) any alternative fuel (other than electricity); or generating, transmitting, importing, or selling (at wholesale and retail) electricity; or if that fuel provider produces, imports, or produces and imports (in combination), an average of 50,000 barrels per day of petroleum and 30% (a substantial portion) or more of its gross annual revenues are derived from producing alternative fuels.
Alternative Fuel Vehicle (AFV)
As defined by the Energy Policy Act, any dedicated, flexible-fuel, or dual-fuel vehicle designed to operate on at least one alternative fuel.
Alternative Fuels Data Center (AFDC)
A program sponsored by DOE and managed by the National Renewable Energy Laboratory to collect data and information on all types of Alternative Fuels and AFVs across the country.
Alternative Fuels Utilization Program (AFUP)
A program managed by DOE with the goals of improving national energy security by displacing imported oil, improving air quality by development and widespread use of alternative fuels for transportation, and increasing the production of AFVs.
Alternative Motor Fuels Act of 1988 (AMFA)
Public Law 100-494. Encourages the development, production and demonstration of alternative motor fuels and AFVs.
American Society for Testing and Materials (ASTM)
A nonprofit organization that provides a management system to develop published technical information. ASTM standards, test methods, specifications, and procedures are recognized as definitive guidelines for motor fuel quality as well as a broad range of other products and procedures.
Describes a compound that does not contain any water. Ethanol produced for fuel use is often referred to as anhydrous ethanol, as it has had almost all water removed.
Hydrocarbons based on the ringed six-carbon benzene series or related organic groups. Benzene, toluene and xylene are the principal aromatics, commonly referred to as the BTX group. They represent one of the heaviest fractions in gasoline.
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100% (neat) biodiesel.
A blend of biodiesel fuel with petroleum-based diesel where 20% of the volume is biodiesel.
Industry term referring to the group of aromatic hydrocarbons—benzene, toluene and xylene (see aromatics).
Balance of Payments
The dollar amount difference between a country's exports and imports. In the United States, large oil imports are one of the main causes of the negative balance of payments with the rest of the world.
A six-carbon aromatic; common gasoline component identified as being toxic. Benzene is a known carcinogen.
A vehicle with two separate fuel systems designed to run on either an alternative fuel, or gasoline or diesel, using only one fuel at a time. Bi-fuel vehicles are referred to as "dual-fuel" vehicles in the Clean Air Act Amendments and Energy Policy Act.
The use of enzymes and catalysts to change biological substances chemically to produce energy products. For example, the digestion of organic wastes or sewage by microorganisms to produce methane is a biochemical process.
A biodegradable transportation fuel for use in diesel engines that is produced through transesterification of organically derived oils or fats. Biodiesel is used as a component of diesel fuel. In the future it may be used as a replacement for diesel.
A fuel that is non-petroleum based. It has no or very little carbon content and the base/feedstock material is usually vegetative. When the biofuel is blended with conventional petroleum based fuels the result is a cleaner burn and thus less carbon based pollution.
A gaseous product of the anaerobic digestion (decomposition without oxygen) of organic matter. It is typically made up of 50-80% methane, 20-50% carbon dioxide, and traces of gases such as hydrogen, carbon monoxide, and nitrogen. In contrast, natural gas is typically made up of more than 70% methane, with most of the rest being other hydrocarbons (such as propane and butane) and only small amounts of carbon
dioxide and other contaminants. Biogas is sometimes called swamp gas, landfill gas, or digester gas. When its composition is upgraded to a higher standard of purity, it can be called renewable natural gas.
Renewable organic matter such as agricultural crops; crop waste residues; wood, animal, and municipal waste, aquatic plants; fungal growth; etc., used for the production of energy.
The combining of two or more fuels in specific quantities to achieve a desired blend that is identified by a letter preceding a number … for example: E85 refers to a blend of 85% Ethanol and 15% Gasoline; B10 refers to a blend of 10% Biodiesel and 90% Low Sulfur Diesel. The letter refers to the “Renewable Fuel”.
A platform mounted system for blending fuels of different types. (See “Fuel Blending”)
British Thermal Unit (Btu)
A standard unit for measuring heat energy. One Btu represents the amount of heat required to raise one pound of water one degree Fahrenheit (at sea level).
A large quantity of fuel usually kept in large field storage tanks or “fuel farms”. This term can also apply to rail tank cars and tank trucks.
A 4-carbon alcohol (butyl alcohol). Biobutanol is butanol produced from biomass feedstocks. Currently, butanol's primary use is as an industrial solvent in products such as lacquers and enamels. Like
ethanol, biobutanol is a liquid alcohol fuel that can be used in today's gasoline-powered internal combustion engines. The properties of biobutanol make it highly amenable to blending with gasoline. It is also compatible
with ethanol blending and can improve the blending of ethanol with gasoline. The energy content of biobutanol is 10 to 20 percent lower than that of gasoline.
A gas, easily liquefied, recovered from natural gas. Used as a low-volatility component of motor gasoline, processed further for a high-octane gasoline component, used in LPG for domestic and industrial applications and used as a raw material for petrochemical synthesis.
Alcohol derived from butane that is used in organic synthesis and as a solvent.
Material, other than the principal product, generated as a consequence of an industrial process or as a breakdown product in a living system.
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Carbon Dioxide (CO2)
A product of combustion that has become an environmental concern in recent years. CO2 does not directly impair human health, but is a greenhouse gas that traps the Earth's heat and contributes to the potential for global warming.
Carbon Monoxide (CO)
A colorless, odorless gas produced by the incomplete combustion of fuels with a limited oxygen supply, as in automobile engines. According to the U.S. Environmental Protection Agency, CO contributes to the formation of smog ground-level ozone, which can trigger serious respiratory problems.
The absorption and storage of CO2 from the atmosphere by the roots and leaves of plants; the carbon builds up as organic matter in the soil.
Chemicals and other substances known to cause cancer.
A substance whose presence changes the rate of chemical reaction without itself undergoing permanent change in its composition. Catalysts may be accelerators or retarders. Most inorganic catalysts are powdered metals and metal oxides, chiefly used in the petroleum, vehicle, and heavy chemical industries.
A family of enzymes that break down cellulose into glucose molecules.
A carbohydrate that is the principal component of wood. It is made of linked glucose molecules that strengthens the cell walls of most plants.
Ignition performance rating of diesel fuel. Diesel equivalent to gasoline octane.
Chemical Injection or Additive Injection
This refers to a blended component to the final fuel. The additive is introduced to the flow stream as it is being metered and is controlled via the system PLC – Programmable Logic Controller.
Clean Air Act (CAA)
Signed into law in 1963, then amended in 1970, and again in 1990 (see Clean Air Act Amendments of 1990). Includes emissions standard for mobile and stationary sources. Enforced by the U.S. Environmental Protection Agency.
An evolving definition of diesel fuel with lower emission specifications, which strictly limit sulfur content to 0.05 weight %; in California, aromatics content is further limited to 10 volume % (for large refiners).
Any fuel or power source that is used to certify a vehicle to the LEV, ILEV, ULEV, SULEV, or ZEV standard.
Clean Fuel Fleet Program
Implemented by the U.S. Environmental Protection Agency as a provision of the Clean Air Act Amendments of 1990 to require cities with significant air quality problems to incorporate vehicles that will meet clean fuel emissions standards.
Clean Fuel Vehicle (CFV)
Any vehicle certified by EPA as meeting certain federal emissions standards. The three categories of federal CFV standards from least to most stringent are low emission vehicles (LEVs), ultra-low emission vehicles (ULEVs), and zero emission vehicles (ZEVs). The inherently low emission vehicle (ILEV) standard is voluntary and does not need to be adopted by states as part of the Clean-Fuel Fleet Program. CFVs are eligible for two federal programs, the California Pilot Program and the Clean-Fuel Fleet Program. CFV exhaust emissions standards for light-duty vehicles and light-duty trucks are numerically similar to those of CARB's California Low-Emission Vehicle Program.
Heavier molecular weight alcohols used with methanol to improve water tolerance and reduce other negative characteristics of gasoline/alcohol blends. Tertiary butyl alcohol (TBA) was used commercially as a co-solvent for methanol/gasoline blends during the 1980s.
Compressed Natural Gas (CNG)
Natural gas that has been compressed under high pressures, typically 2000 to 3600 psi, held in a container. The gas expands when used as a fuel.
The form of ignition that initiates combustion in a diesel engine. The rapid compression of air within the cylinders generates the heat required to ignite the fuel as it is injected.
Congestion Mitigation and Air Quality Improvement (CMAQ) Program
A federal grant program established by the Intermodal Surface Transportation Act of 1991 that allocates funds to states to help them simultaneously expand or initiate transportation services while improving air quality. CMAQ funds may be used to support alternative fuel and alternative fuel vehicle programs.
Converted or Conversion Vehicle
A vehicle originally designed to operate on gasoline or diesel that has been modified or altered to run on an alternative fuel.
Additives used to inhibit corrosion (e.g., rust) in the fuel system.
Extreme low-temperature storage.
In fluid measurement, a custody transfer point is a metering point at a location where the fluid is being measured for sale from one party to another. This term can also denote the transfer of ownership along with related responsibilities and liabilities from one party to another.
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Dedicated Natural Gas Vehicle
A vehicle that operates only on natural gas. Such a vehicle is incapable of running on any other fuel.
A vehicle that operates solely on one fuel. Generally, dedicated vehicles have superior emissions and performance results because their design has been optimized for operation on a single fuel.
Ethanol that contains a small amount of a toxic substance, such as methanol or gasoline, which cannot be removed easily by chemical or physical means. Alcohols intended for industrial use must be denatured to avoid federal alcoholic beverage tax.
Department of Energy
See U.S. Department of Energy (DOE).
Additives used to inhibit deposit formation in the fuel and intake systems in automobiles.
Digital Control Meter
A meter in the fuel stream of the metering system that is activated via a PLC – Programmable Logic Controller. Entries are made to the PLC and all operation of the system is electronic.
Dimethyl Ether (DME)
An oxygenated hydrocarbon, which is the simplest compound in the class of ethers. It is generally produced from natural gas but almost any carbon-based feedstock can be used, including crude oil, coal, crop residues, oil sands, wood, or straw.
The percentages of gasoline that evaporate at various temperatures. The distillation curve is an
important indicator for fuel standards such as volatility (vaporization).
As defined by the Energy Policy Act, Section 301, domestic fuel is derived from resources within the United States, its possessions and commonwealths, and Canada and Mexico (the two nations in a free-trade agreement with the United States).
Vehicle designed to operate on a combination of an alternative fuel and a conventional fuel. This includes (a) vehicles that use a mixture of gasoline or diesel and an alternative fuel in one fuel tank, commonly called flexible-fuel vehicles; and (b) vehicles capable of operating either on an alternative fuel, a conventional fuel, or both, simultaneously using two fuel systems. They are commonly called bi-fuel vehicles.
An instrument for measuring mechanical force, or an apparatus for measuring mechanical power (as of an engine).
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Ethanol mixture that contains 10% ethanol, 90% unleaded gasoline.
Ethanol/gasoline mixture that contains 85% denatured ethanol and 15% gasoline, by volume.
Ethanol mixture that contains 93% ethanol, 5% methanol and 2% kerosene, by volume.
Ethanol/gasoline mixture that contains 95% denatured ethanol and 5% gasoline, by volume.
Electric current used as a power source. Electricity can be generated from a variety of feedstocks, including oil, coal, nuclear, hydro, natural gas, wind, and solar. In electric vehicles, onboard rechargeable batteries power electric motors.
Emergency Stop (E-Stop)
A device associated with the loading and unloading of fuel that can deactivate/shutdown the entire operation if activated. The E-Stop device is usually a manually activated large, red mushroom-shaped push button within easy access by anyone in the immediate area.
Limits or ranges established for pollution levels emitted by vehicles as well as stationary sources. The first standards were established under the 1963 Clean Air Act. Emission limits are imposed on four classes of vehicles: automobiles, light-duty trucks, heavy-duty gasoline trucks, and heavy-duty diesel trucks.
A crop grown specifically for its fuel value. These include food crops such as corn and sugarcane, and nonfood crops such as poplar trees and switchgrass.
Energy Policy Act of 1992 (EPAct)
Passed by Congress to enhance U.S. energy security by reducing our dependence on imported oil. It mandates the use of alternative fuel vehicles, beginning with federal, then state, then fuel provider fleets.
Environmental Protection Agency
See U.S. Environmental Protection Agency (EPA)
An organic compound formed by reacting an acid with an alcohol, always resulting in the elimination of water.
A colorless hydrocarbon gas of slight odor having a gross heating value of 1,773 Btu per cubic foot. It is a normal constituent of natural gas.
Ethanol (also known as Ethyl Alcohol, Grain Alcohol, CH 3 CH 2 OH)
Can be produced chemically from ethylene or biologically from the fermentation of various sugars from carbohydrates found in agricultural crops and cellulosic residues from crops or wood. Used in the United States as a gasoline octane enhancer and oxygenate, it increases octane 2.5 to 3.0 numbers at 10% concentration. Ethanol also can be used in higher concentration in alternative fuel vehicles optimized for its use.
A class of organic compounds containing an oxygen atom linked to two organic groups.
Oxygenation of an olefin by methanol or ethanol. For example, MTBE is formed from the chemical reaction of isobutylene and methanol.
A fatty ester formed when organically derived oils are combined with ethanol in the presence of a catalyst. After water washing, vacuum drying, and filtration, the resulting ethyl ester has characteristics similar to petroleum-based diesel motor fuels.
Ethyl Tertiary Butyl Ether (ETBE)
A fuel oxygenate used as a gasoline additive to increase octane and reduce engine knock. Evaporative Emissions Hydrocarbon vapors that escape from a fuel storage tank or a vehicle fuel tank or vehicle fuel system.
Explosion-Proof (XP) Apparatus
Article 500 of the National Fire Protection Association code defines an “Explosion Proof Apparatus” as being enclosed in a case that is capable of withstanding an explosion of a specified gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby.
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Any material converted to another form of fuel or energy product. For example, cornstarch can be used as a feedstock for ethanol production.
The enzymatic transformation by microorganisms of organic compounds such as sugar. It is usually accompanied by the evolution of gas as the fermentation of glucose into ethanol and CO2.
A method discovered in 1923 by the German coal researchers Franz Fischer and Hans Tropsch, for the synthesis of hydrocarbons and other aliphatic compounds. A mixture of hydrogen and carbon monoxide is reacted in the presence of an iron or cobalt catalyst. Much heat is evolved and products such as methane, synthetic gasoline and waxes, and alcohols are made. Water or carbon dioxide is its by-product.
Fixed - Mobile Transloading
A system for transferring fuel from one mobile container (rail car) to another (tank truck) without being stored. This system may be fixed on a platform or mobile with wheels so it may be moved from one location to another. (See “Transloading”).
Flexible-Fuel Vehicle (FFV)
A Vehicle with a common fuel tank designed to run on varying blends of unleaded gasoline with either ethanol or methanol.
A fuel such as coal, oil, and natural gas. Fossil fuels are the remains of ancient plants and animals.
The method of combining two or more fuels in specific quantities to achieve a desired blend. There are two customary methods of blending: ratio and sequential. Ratio blending is the method of combining the fuels in the flowstream at predetermined percentages, for example: 90% gasoline/10% ethanol. Sequential blending is the method of loading out the fuel in predetermined quantities that make up the percentages, for example: 900 gallons of gasoline (90%)/100 gallons of ethanol (10%). Sequential blending is usually referred to as “splash” blending. Splash blending is not always an accepted method of blending as it lacks true control and verification.
An electrochemical engine with no moving parts that converts the chemical energy of a fuel, such as hydrogen, and an oxidant, such as oxygen, directly to electricity. The principal components of a fuel cell are catalytically activated electrodes for the fuel (anode) and the oxidant (cathode) and an electrolyte to conduct ions between the two electrodes.
The method of measuring the amount of fuel being transferred with an engineered device that is calibrated to report the volume of fuel flow. There are three commonly used meters of fuel: Positive Displacement-PD, Turbine and Coriolis (usually referred to as Mass Flow).
Fuel Metering Skid
A self-contained system that is mounted on a base or platform that measures the amount of fuel being transferred. The fuel metering skid can be a single product or multiple product that can be blended. The metering skid has engineered components or devices that make up the system to accomplish “custody transfer” of the fuel from one party to the other. The system component makeup is required for accounting purposes and for tax reporting to state and federal agencies. The system must be “proved” or certified by the agencies for accuracy. The most recognizable way to identify this proof is on the gasoline pump at the local filling station. There is a stamp placed on each pump that certifies the accuracy of the pump/dispenser and that it is legal for trade. The stamp is usually placed there by the state Agricultural Department, Board of Weights and Measures.
Emissions (air pollutants) released to the air other than those from stacks or vents. They are often due to equipment leaks, evaporative processes, and windblown disturbances.
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Gas to Liquid Technology
Gas-to-liquid conversion technologies use chemical or physical means to convert natural gas to a liquid form suitable for ready transport or direct use.
In the United States, gasohol (E10) refers to gasoline that contains 10% ethanol by volume. This term was used in the late 1970s and early 1980s but has been replaced in some areas of the country with E10, super unleaded plus ethanol, or unleaded plus.
Gasoline Gallon Equivalent (GGE)
A unit for measuring alternative fuels so that they can be compared with gasoline on an energy equivalent basis. This is required because the different fuels have different energy densities.
The theoretical escalation of global temperatures caused by the increase of greenhouse gas emissions in the lower atmosphere.
A six-carbon fermentable sugar.
A liquid by-product of biodiesel production. Glycerin is used in the manufacture of dynamite, cosmetics, liquid soaps, inks, and lubricants.
A warming of the Earth and its atmosphere as a result of the thermal trapping of incoming solar radiation by CO2, water vapor, methane, nitrogen oxide, chlorofluorocarbons, and other gases, both natural and man-made.
Gross Vehicle Weight Rating (GVWR)
Maximum weight of a vehicle, including payload.
Grounding Monitor (Ground Verification)
A device associated with the loading and unloading of fuel that reports the grounding status of the operation. Safe operation of the loading and unloading requires that the truck and/or railcar be grounded. The monitor can be visual only or it can be made to deactivate/shutdown the entire operation if grounding is lost.
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Hazmat (Hazardous Material)
DOT (U.S. Department of Transportation) defines a hazardous material as any item or chemical which, when being transported or moved, is a risk to public safety or the environment.
Generally, a vehicle that has a GVWR of more than 26,000 lb. Definitions vary by organization.
High Occupancy Vehicle (HOV) Lanes
Lanes on the highway that are restricted to vehicles carrying more than one passenger.
Hybrid Electric Vehicle (HEV)
A vehicle powered by two or more energy sources, one of which is electricity. HEVs may combine the engine and fuel of a conventional vehicle with the batteries and electric motor of an electric vehicle in a single drivetrain.
An organic compound that contains only hydrogen and carbon. In vehicle emissions, these are usually vapors created from incomplete combustion or from vaporization of liquid gasoline. Emissions of hydrocarbons contribute to ground level ozone.
A chemical reaction that releases sugars, which are normally linked together in complex chains. In ethanol production, hydrolysis reactions are used to break down the cellulose and hemicellulose in the biomass.
A colorless, highly flammable gaseous fuel.
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In transportation, this term generally refers to the charging and fueling network necessary to successful development, production, commercialization, and operation of alternative fuel vehicles. It includes fuel supply, public and private charging and fueling facilities, standard specifications for fueling outlets, customer service, education and training, and building code regulations.
Inherently Low Emission Vehicle (ILEV)
This is a federal standard only. Such a vehicle meets EPA CFV ILEV exhaust emission standards and produces very few or no evaporative emissions (5 grams or less per test without using auxiliary emission control devices). ILEVS are dedicated AFVs in most cases. Dual-fuel vehicles will be considered ILEVs only if both fuels meet the standard. ILEV credits can be banked in the Consolidated Metropolitan Statistical Area.
According to Article 504 of the National Electrical Code, NFPA 70, an intrinsically safe electrical circuit is defined as one in which no spark or thermal effect generated during normal functioning and/or during specific fault conditions is able to ignite a given explosive atmosphere.
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A vegetable oil produced from the seeds of the Jatropha curcas, a plant that can grow in marginal lands and common lands. When jatropha seeds are crushed, the resulting jatropha oil can be processed to produce a high-quality biodiesel that can be used in a standard diesel car, while the residue can also be processed and used as biomass feedstock to power electricity plants or used as fertilizer (it contains nitrogen, phosphorous and potassium). The plant may yield more than four times as much fuel per hectare as soybean, and more than ten times that of corn. A hectare of jatropha has been claimed to produce 1,892 litres of fuel. However, as it has not yet been domesticated or improved by plant breeders, yields are variable.
(Thanks to Biofuel Digest for this definition)
LNG to CNG Station
A station, supplied with LNG, that pumps and vaporizes the liquid supply to vehicles as CNG fuel, generally at the correct pressure and temperature (i.e., the temperature effect of compression is factored into the design).
A vehicle that uses Liquid Natural Gas as its fuel.
see Tetraethyl Lead.
Passenger cars and trucks with a gross vehicle weight rating of 8,500 or less.
Liquefied Natural Gas (LNG)
Compressed natural gas that is cryogenically stored in its liquid state.
Liquefied Petroleum Gas (LPG)
A mixture of hydrocarbons found in natural gas and produced from crude oil, used principally as a feedstock for the chemical industry, home heating fuel, and motor vehicle fuel. Also known by the principal constituent propane.
A metric measurement used to calculate the volume displacement of an engine. One liter is equal to
1,000 cubic centimeters or 61 cubic inches.
A device used for loading or unloading that is usually a hard-piped extension of the piping system. The loading arm is usually assisted by a spring, a pneumatic or hydraulic cylinder and can be articulated by an operator to couple to or insert into a railcar or truck. The advantage of a loading arm over a typical loading hose is that it is ergonomically correct and operator friendly for repeated use and returns to the same position for storage.
A term used to describe the process of transferring fuel from a storage facility or tank into a tank truck or tank car for distribution. Load Out Arm - See “Loading Arm” above.
Capacity to reduce friction.
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100% (neat) methanol.
85% methanol and 15% unleaded gasoline by volume, used as a motor fuel in FFVs.
Manual Preset Meter
A stand-alone meter in the fuel stream that allows the entry of gallons to be transferred made manually. The metering system activation is made via a lever-operated valve that triggers the pump “start” to move the fuel through the system. The fuel flow is hydraulically registered through the manual preset meter.
Typically, a vehicle with a GVWR of 8,500 to 14,000 lb.
The simplest of the hydrocarbons and the principal constituent of natural gas. Pure methane has a heating value of 1,012 Btu per standard cubic foot.
Methanol (also known as Methyl Alcohol, Wood Alcohol, CH3 OH)
A liquid fuel formed by catalytically combining CO with hydrogen in a 1 to 2 ratio under high temperature and pressure. Commercially, it is typically manufactured by steam reforming natural gas. Also formed in the destructive distillation of wood.
A fatty ester formed when organically derived oils are combined with methanol in the presence of a catalyst. Methyl Ester has characteristics similar to petroleum-based diesel motor fuels.
Methyl Tertiary Butyl Ether (MTBE)
A fuel oxygenate used as an additive to gasoline to increase octane and reduce engine knock. According to the U.S. Environmental Protection Agency, MTBE has been detected in ground water across the country, sometimes contaminating drinking water. Recent work by EPA and other researchers is expected to help determine the potential for health effects from MTBE in drinking water.
Mobile Source Emissions
Emissions resulting from the operations of any type of motor vehicle.
The octane as tested in a single-cylinder octane test engine at more severe operating conditions. Motor octane number (MON) affects high-speed and part-throttle knock and performance under load, passing, climbing, and other operating conditions. Motor octane is represented by the designation M in the (R+M)/2 equation and is the lower of the two numbers.
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National Ambient Air Quality Standards (NAAQS)
Ambient standards for air pollutants specifically regulated under the CAA. These pollutants include ozone, CO, NO2, lead, PM, and SOx.
A mixture of gaseous hydrocarbons, primarily methane, occurring naturally in the Earth and used principally as a fuel.
Natural Gas Distribution System
This term generally applies to mains, services, and equipment that carry or control the supply of natural gas from a point of local supply, up to and including the sales meter.
Natural Gas Transmission System
Pipelines installed for the purpose of transmitting natural gas from a source or sources of supply to one or more distribution centers.
Natural Gas Vehicle
Vehicles that are powered by compressed or liquefied natural gas.
Near Neat Fuel
Fuel that is virtually free from admixture or dilution.
Neat Alcohol Fuel
Straight or 100% alcohol (not blended with gasoline), usually in the form of either ethanol or methanol.
Fuel that is free from mixture or dilution with other fuels.
Non-Methane Organic Gases (NMOG)
The sum of non-oxygenated and oxygenated hydrocarbons (exclusive of methane) contained in a gas sample as measured in accordance with California's non-methane organic gas test procedure.
A non-renewable energy resource is one that cannot be replaced as it is used. Although fossil fuels, like coal and oil, are in fact fossilized biomass resources, they form at such a slow rate that, in practice, they are non-renewable.
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Original equipment manufacturer.
Any substance such as MTBE, ETBE, toluene, or xylene that is added to gasoline to increase octane and reduce engine knock.
Octane Rating (Octane Number)
A measure of a fuel's resistance to self-ignition, hence a measure as well of the antiknock properties of the fuel.
Any non-stationary device, powered by an internal combustion engine or motor, used primarily off the highways to propel, move, or draw persons or property, and used in any of the following applications: marine vessels, construction/farm equipment, locomotives, utility and lawn and garden equipment, off-road motorcycles, and off-highway vehicles.
Office of Transportation and Air Quality
Division of EPA that protects public health and the environment by controlling air pollution from motor vehicles, engines, and the fuels used to operate them, and by encouraging travel choices that minimize emissions.
Onboard Refueling Vapor Recovery (ORVR)
System required on vehicles beginning in 1998 to control refueling emissions.
Open-Loop Fuel Control
System in which the air/fuel mixture is preset by design with no feedback correction signal to optimize fuel metering.
Original Equipment Manufacturer (OEM)
The original manufacturer of a vehicle or engine.
A valve installed at the fill port of an above ground storage tank to terminate product flow when the liquid level reaches a preset level. Other methods include but are not limited to berms, liners and other secondary containment should a leak or spill occur and overfill alarms. Overfill alarms use probes installed in the tank to activate an alarm when the tank is either (approximately) 90 percent full or within 1 minute of being overfilled.
Oxides of Nitrogen (NOx)
Regulated air pollutants, primarily NO and NO2 but including other substances in minute concentrations. Under the high pressure and temperature conditions in an engine, nitrogen and oxygen atoms in the air react to form various NOx. Like hydrocarbons, NOx are precursors to the formation of smog. They also contribute to the formation of acid rain.
A term used in the petroleum industry to denote fuel additives containing hydrogen, carbon, and oxygen in their molecular structure. Includes ethers such as MTBE and ETBE and alcohols such as ethanol and methanol.
Fuels blended with an additive, usually methyl tertiary butyl ether (MTBE) or ethanol to increase oxygen content, allowing more thorough combustion for reduced carbon monoxide emissions.
Gasoline containing an oxygenate such as ethanol or MTBE. The increased oxygen content promotes more complete combustion, thereby reducing tailpipe emissions of CO.
Tropospheric ozone (smog) is formed when volatile organic compounds (VOCs), oxygen, and NOx react in the presence of sunlight (not to be confused with stratospheric ozone, which is found in the upper atmosphere and protects the earth from the sun's ultraviolet rays). Though beneficial in the upper atmosphere, ground-level ozone is a respiratory irritant and considered a pollutant.
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Fuels designed by the Pure Fuel Corporation to run in E85/gasoline flexible fuel vehicles. Added by DOE after EPAct as an alternative fuel.
Group of saturated aliphatic hydrocarbons, including methane, ethane, propane, and butane and noted
by the suffix "-ane".
Particulate Matter (PM)
A generic term for a broad class of chemically and physically diverse substances that exist as discrete particles (liquid droplets or solids) over a wide range of sizes. A NAAQS pollutant.
Diesel vehicle emission control device that traps and incinerates diesel particulate emissions after they are exhausted from the engine but before they are expelled into the atmosphere.
Gasoline or diesel fuel.
The phenomenon of a separation of a liquid or vapor into two or more physically distinct and mechanically separable portions or layers.
Programmable Logic Controller – This is another term for the Load Controller and refers to the electronic device that totally controls the skid metering system from the pump activation for fuel flow to the final reporting of the metered fuel for accounting and billing.
Portable Fueling System
A system designed to deliver natural gas to fueling stations. Such systems are usually configured as tube trailers and are mobile. Fuel delivery usually occurs via over-the-road vehicles.
Pounds Per Square Inch (PSI)
A unit of measure for pressure.
A fleet of vehicles owned by a non government entity.
A gas whose molecules are composed of three carbon and eight hydrogen atoms. Propane is present in most natural gas in the United States, and is refined from crude petroleum. Propane contains about 2,500 Btu per standard cubic foot. Propane is the principal constituent in liquified petroleum gas (LPG).
A blend of natural gas liquids (pentanes plus), ethanol, and the biomass-derived co-solvent methyltetrahydrofuran (MeTHF). P-Series fuels are clear, colorless, 89-93 octane, liquid blends that are formulated to be used in flexible fuel vehicles (FFVs). P-Series fuel can be used alone or freely mixed with gasoline in any proportion inside an FFV fuel tank. Currently, P-Series is not being produced in large
quantities and is not widely used. P-Series is the only fuel to be added to the list of authorized alternative fuels under the Energy Policy Act of 1992 (EPAct). It was added to the list through the EPAct petitions
provision in 1999.
Public Fueling Station
Refers to fueling station that is accessible to the general public.
The octane as posted on retail gasoline dispensers as (R+M)/2; same as Antiknock Index.
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Reactivity Adjustment Factor (RAF)
An NMOG adjustment used in the certification of vehicles to the California emission standards to reflect reduced ozone forming potential of a fuel, especially alternative fuels.
Reformulated Gasoline (RFG)
Gasolines that have had their compositions or characteristics altered to reduce vehicular emissions of pollutants, particularly pursuant to EPA regulations under the CAA.
VOC vapors that escape from the vehicle fuel tank during refueling. Storage II pump controls and onboard refueling vapor recovery systems (ORVR) are intended to control these emissions.
Reid Vapor Pressure (RVP)
A standard measurement of a liquid's vapor pressure in psi at 100°F. It is an indication of the propensity of the liquid to evaporate.
Another term for biofuel as the base/feedstock material from which the fuel is manufactured can be renewed or grown again. Once petroleum based fuels are burned they are depleted.
Renewable Identification Number – The 38-digit number required by RFS1 – Renewable Fuels Standard for tracking and managing the transactions from the manufacturer/producer to the distributor. On July 1, 2010 under final rule RFS2 a new system, EMTS – EPA Moderated Transaction System, will go into effect and used to generate, sell, buy, separate or retire RINs as they are now known.
Research Octane Number (RON)
The octane as tested in a single-cylinder octane test engine operated under less severe operating conditions. RON affects low-to medium-speed knock and engine run-on. Research Octane is presented by the designation R in the (R+M)/2 equation and is the higher of the two numbers.
To change a vehicle or engine after its original purchase, usually by adding equipment such as conversion systems.
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Scrubber systems are a diverse group of air control devices that can be used to remove some particulates and/or gases from industrial exhaust streams. Traditionally, the term "scrubber" has referred to pollution control devices that use liquid to wash unwanted pollutants from a gas stream. Recently, the term is also used to describe systems that inject a dry reagent or slurry into a dirty exhaust stream to "wash out" acid gases. Scrubbers are one of the primary devices that control gaseous emissions, especially acid gases. Scrubbers can also be used for heat recovery from hot gases by flue gas condensation.
A self-contained system that is mounted on a base or platform that serves as the boundary for the system. The skid can be fixed/permanently mounted or mobile/wheeled. The configuration of the skid and the rage of operation the skid performs is the choice of the customer … from “basic” to “controlled”.
A visible haze caused primarily by particulate matter and ozone. Ozone is formed by the reaction of hydrocarbons and NOx in the atmosphere.
Spark Ignition Engine
Internal combustion engine in which the charge is ignited electrically (e.g., with a spark plug).
SPCC – Spill Prevention, Control and Countermeasures Rule
The Federal Water Pollution Control Act (as amended by The Clean Water Act) the SPCC rule took effect on January 10, 1974. Its purpose is to prevent oil and oil-related materials from reaching navigable waters and adjoining shorelines.
A device or system that is used to capture a spill event. The provision for spill containment typical at loading and unloading spots is identified in the Federal Water Pollution Control Act as the SPCC Rule. The typical device for railcar spill containment is a track pan system. For truck loading and unloading spots, the spill containment is usually designed and incorporated into the concrete pad layout.
State Energy Program
Program offered by the U.S. Department of Energy that allows states to compete for funding to implement activities related to programmatic areas, such as federal energy management, building codes and standards, alternative fuels, industrial efficiency, building efficiency, and renewable energy technologies.
Sulfur Dioxide (SO2)
An EPA criteria pollutant
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In general, a means of employing the tax code to stimulate investment in or development of a socially desirable economic objective without direct expenditure from the budget of a given unit of government. Such incentives can take the form of tax exemptions or credits.
Tertiary Amyl Ethyl Ether (TAEE)
An ether based on reactive C5 olefins and ethanol.
Tertiary Amyl Methyl Ether (TAME)
An ether based on reactive C5 olefins and methanol.
Tetraethyl Lead or Lead
An octane enhancer. One gram of lead increases the octane of one gallon of gasoline about 6 numbers. The EPA has phased down the use of lead in gasoline as it has been determined to be a health hazard. Lead has been prohibited in highway vehicle gasoline since January 1, 1996.
A unit of heating value equivalent to 100,000 British Thermal Units (Btu).
Basic aromatic compound derived from petroleum and used to increase octane. The most common
hydrocarbon purchased for use in increasing octane.
Any pollutant emitted from a source that can negatively affect human health or the environment.
A generic term referring to a harmful substance or group of substances. Typically, these substances are especially harmful to health, such as those considered under EPA's hazardous substance program. Technically, any compound that has the potential to produce adverse health effects is considered a toxic substance.
The device used for spill containment at rail spurs when railcars are being loaded or unloaded. The track pan can be made from any material that will maintain a permanent shape that can be modified to fit between and/or beside rail tracks. There are track pans available made of metal – carbon and stainless steel, polyethylene and fiberglass. A track pan system is utilized to comply with the Federal SPCC – Spill Prevention, Control and Countermeasures Rule.
A process in which organically derived oils or fats are combined with alcohol (ethanol or methanol) in the presence of a catalyst to form esters (ethyl or methyl ester).
Transitional Low-Emission Vehicle (TLEV)
Describes a vehicle that meets either EPA's CFV TLEV standards or CARB's California Low-Emission Vehicle Program TLEV standards. TLEVs produce fewer emissions than federal Tier 1 vehicles. TLEVs are eligible for the federal California Pilot Program but not eligible for the Clean-Fuel Fleet Program.
This is the commonly referred to method of transferring fuel from a railcar to a truck without having it sent to storage first. There can be two types of transloading – fixed or mobile. A “fixed” transloader unit is usually a permanently mounted pump and metering skid that is positioned adjacent to a rail spur equipped with a railcar suction header. The railcars are spotted along the suction header for coupling to the railcar drain valve. The “mobile” transloader unit has wheels to accomplish the task and can be moved from railcar to railcar to empty them one-at-a-time.
Complete and ready for use. In the context of this website, “turn key” means a system that is completely fabricated, installed, wired and ready for start up.
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U.S. Department of Energy (DOE)
A department of the federal government, established by the Carter Administration in 1977, to consolidate energy-oriented programs and agencies. The DOE mission includes the coordination and management of energy conservation, supply, information dissemination, regulation, research, development and demonstration.
U.S. Department of Transportation
A government agency whose mission is to ensure a fast, safe, efficient, accessible, and convenient transportation system that meets the national interests and enhances our quality of life.
U.S. Environmental Protection Agency (EPA)
A government agency, established in 1970, responsible for protecting the environment and public health. EPA seeks to reduce air, water, and land pollution and pollution from solid waste, radiation, pesticides, and toxic substances. EPA also controls emissions from motor vehicles, fuels, and fuel additives.
Ultra-low Sulfur Diesel (ULSD)
A diesel fuel with 15 parts per million (ppm) or lower sulfur content. This ultra-low sulfur content enables use
of advanced emission control technologies on light-duty and heavy-duty diesel vehicles. Most highway diesel fuel refined in or imported into the United States is required to be ULSD. One hundred percent must be ULSD
nationwide by 2010.
Ultra-Low-Emission Vehicle (ULEV)
Describes a vehicle that meets either EPA's CFV ULEV standards or CARB's California Low-Emission Vehicle Program ULEV standards. ULEVs produce fewer emissions than LEVs. Fleets that purchase CFV ULEVs may earn credits under the Clean-Fuel Fleet Vehicle Program. Manufacturers that sell CFV ULEVs may earn credits under the federal California Pilot Program.
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Vapor Pressure or Volatility
The tendency of a liquid to pass into the vapor state at a given temperature. With automotive fuels, volatility is determined by measuring RVP.
When a liquid is pumped into an empty or partially full tank vapors contained in the tank are displaced and are forced out through the fill opening. A vapor return system allows these vapors to be captured and returned to the filling vessel averting their release into the atmosphere.
Variable Fuel Vehicle (VFV)
A vehicle that has the capacity of burning any combination of gasoline and an alternative fuel. Also known as a flexible-fuel vehicle.
Retrofitting a vehicle engine to run on an alternative fuel.
Volatile Organic Compound (VOC)
Reactive gas released during combustion or evaporation of fuel and regulated by EPA. VOCs react with NOx in the presence of sunlight and form ozone.
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Wheeled Transloader (Transloading Skid)
A mobile system with wheels for transferring fuel from one mobile container (rail car) to another (tank truck) without being stored. (See “Transloading”)
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(See “Explosion Proof”)
An aromatic hydrocarbon derived from petroleum and used to increase octane. Highly valued as a petrochemical feedstock. Xylene is highly photochemically reactive and, as a constituent of tailpipe emissions, is a contributor to smog formation.
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Zero Emission Vehicle (ZEV)
A vehicle that emits no tailpipe exhaust emissions. ZEV credits can be banked within the Consolidated Metropolitan Statistical Area.