Anthropogenic CO2 Emissions: caused or influenced by humans; anthropogenic carbon dioxide is that portion of carbon dioxide in the atmosphere that is produced directly by human activities, such as the burning of fossil fuels, rather than by natural processes like respiration and decay.

Biogenic CO2 Emissions: “non-fossilized and biodegradable organic material originating from plants, animals, or microorganisms (including products, by-products, residues and waste from agriculture, forestry and related industries as well as the non-fossilized and biodegradable organic fractions of industrial and municipal waste, including gases and liquids recovered from the decomposition of non-fossilized and biodegradable organic material” (EPA, 2011).

EXAMPLE of Biogenic CO2: In the biogenic carbon cycle, plants constantly remove carbon from the atmosphere through photosynthesis and emit carbon into the atmosphere through natural processes, including respiration and decay. In contrast the carbon contained in, fossil fuels, such as coal, oil, and natural gas, has been trapped beneath the earth for millions of years. When carbon from these materials is released into the atmosphere, millions of tons per year of “new carbon” are added to the natural carbon cycle.

Biofuel: Solid, liquid or gaseous fuel that is derived from biomass; biomass that has been processed or converted into a more convenient form, principally to increase energy density; this may involve physical pre-processing simply to cut it into more manageable pieces or reduce the moisture content, or may involve thermal or chemical processing to convert it into a solid, liquid or gas.

Biomass: biological material derived from living, or recently living organisms. In the context of biomass for energy this is often used to mean plant based material, but biomass can equally apply to both animal and vegetable derived material; biomass takes carbon out of the atmosphere while it is growing, and returns it as it is burned; if it is managed on a sustainable basis, biomass is harvested as part of a constantly replenished crop.

British Thermal Unit (BTU): a traditional unit of energy equal to about 1055 joules: the quantity of heat required to raise the temperature of one pound of water one degree Fahrenheit at a specified temperature (as 39°F) at one atmosphere of pressure; the unit is most often used as a measure of power (as BTU/h) in the power, steam generation, heating and air conditioning industries

Carbon Credit: a generic term for any tradable certificate or permit representing the right to emit one metric ton of carbon dioxide, or in some markets, carbon dioxide equivalent gas; carbon credits and carbon markets are a component of national and international attempts to mitigate the growth in concentrations of greenhouse gases (GHGs).

Fischer-Tropsch Process: a catalytic process to synthesize hydrocarbons and their oxygen derivatives by the controlled reaction of hydrogen and carbon monoxide; synthesis gas, a mixture of hydrogen and carbon monoxide, is reacted in the presence of an iron or cobalt catalyst; much heat is evolved, and such products as methane, synthetic gasoline and waxes, and alcohols are made, with water or carbon dioxide produced as a byproduct; the process, a key component of gas to liquids technology, produces a synthetic lubrication oil and synthetic fuel, typically from coal, natural gas, or biomass.

Gasification: a process that converts organic or fossil-based carbonaceous materials into carbon monoxide, hydrogen and carbon dioxide. This is achieved by reacting the material at high temperatures (>700 °C), without combustion, with a controlled amount of oxygen and/or steam. The resulting gas mixture is called syngas (from synthesis gas or synthetic gas) or producer gas and is itself a fuel. The power derived from gasification and combustion of the resultant gas is considered to be a source of renewable energy if the gasified compounds were obtained from biomass.

Greenhouse Gas (GHG): any of the gases whose absorption of solar radiation is responsible for the greenhouse effect including carbon dioxide, methane, ozone, and fluorocarbons.

Homogeneous: uniform in structure or composition throughout; composed of parts or elements that are all of the same kind

Hygroscopic: readily taking up and retaining moisture; taken up and retained under some conditions of humidity and temperature

Municipal Solid Waste (MSW): commonly known as trash or garbage, consisting of everyday items that are discarded by the public; the composition of municipal waste varies greatly from country to country and changes significantly with time

Pathogen: an agent that causes disease, especially a living microorganism such as a bacterium or fungus.

Petroleum Coke (or “Pet Coke”): a solid nonvolatile residue which is obtained as the final still product in the distillation of crude petroleum and whose purity makes it desirable for metallurgical processes, for carbon electrodes, and as a fuel; fuel grade is high in sulphur and metals; anode grade is low in sulphur and metals.

Process Engineered Fuel (PEF): a manufactured product in either shredded form (Fluff®) or densified form that has predictable combustion characteristics. PEF prices, fuel characteristics, and resulting air emissions can be attractive in comparison to other more conventional fuels. Plastics enhance the energy content of these fuels.

Pyrolysis: decomposition or transformation of a compound caused by heat; a thermochemical decomposition of organic material at elevated temperatures in the absence of oxygen; a simultaneous and irreversible change of chemical composition and physical phase

Refuse-derived Fuel (RDF): a fuel produced by processing municipal solid waste (MSW) with a waste converter technology.. The quality of RDF varies greatly from simple ground garbage to modern solid fuels that meet a variety of established quality and environmental standards (see SRF).

Renewable: relating to or being a commodity or resource, such as solar energy or firewood, that is inexhaustible or replaceable by new growth.

Renewable Energy Credit (REC): tradable, non-tangible energy commodities in the United States that represent proof that one megawatt-hour (MWh) of electricity was generated from an eligible renewable energy resource; according to the U.S. Department of Energy’s Green Power Network, RECs represent the environmental attributes of the power produced from renewable energy projects and are sold separately from the actual electricity commodity; RECs incentivize carbon-neutral renewable energy by providing a production subsidy to electricity generated from renewable sources.

Solid Recovered Fuel (SRF): distinguishable from RDF in the fact that it is refined to high quality standards and tested by third-parties to certify conformance with specifications such as the European Committee for Standardization’s CEN/TS 15359.

Sustainable: capable of being continued with minimal long-term effect on the environment.

Synthetic Fuel (or synfuel): a liquid fuel obtained from coal, natural gas, oil shale, or biomass; typically describes fuels manufactured via Fischer Tropsch conversion, methanol to gasoline conversion, or direct coal liquefaction.