and wastewater discharges, the potential for self-generation of power, and the potential for improved pulping operations.

bottoming cycle:

A means to increase the thermal efficiency of a steam electric generating system by converting some waste heat from the condenser into electricity. The heat engine in a bottoming cycle would be a condensing turbine similar in principle to a steam turbine but operating with a different working fluid at a much lower temperature and pressure.


A British thermal unit is a standard unit for measuring the quantity of heat required to raise the temperature of 1 lb of water by 1°F.

CAFE requirements:

Corporate average fuel economy is a sales-weighted average fuel mileage calculation, in terms of miles per gallon, based on city and highway fuel economy measurements performed as part of federal emissions test procedures. CAFE requirements were instituted by the Energy Policy and Conservation Act of 1975 and modified by the Automobile Fuel Efficiency Act of 1980. For major manufacturers, CAFE levels in 1996 were 27.5 miles per gallon for light-duty automobiles. CAFE standards also apply to some light trucks. The Alternative Motor Fuels Act of 1988 allowed for an adjusted calculation of the fuel economy of vehicles that can use alternative fuels, including fuel-flexible and dual-fuel vehicles.

catalytic converter:

An air pollution control device that removes organic contaminants by oxidizing them into carbon dioxide and water through a chemical reaction using a catalyst, which is a substance that increases (or decreases) the rate of a chemical reaction without being changed itself; required in all automobiles sold in the United States and used in some types of heating appliances.


Clean coal technology is a new way to burn or use coal that significantly reduces the release of pollutants and offers greater environmental protection and, often, better economic performance than older coal technologies.


Compact fluorescent lamps are four to five times more efficient than incandescent lamps. CFLs are now widely used in commercial buildings in many applications that traditionally used incandescent lamps, for example, in recessed downlights. The primary barrier to widespread penetration of the CFL in the residential sector is the cost and bulk of the ballast. Unitized lamp-ballast products minimize bulk but tend to be expensive because both the lamp and the ballast are replaced when the product wears out.


Methane is a colorless, odorless gas that is the most simple of the hydrocarbons formed naturally from the decay of organic matter. Each methane molecule contains a carbon atom surrounded by four hydrogen atoms. It is the principal component of natural gas.


Carbon monoxide is a colorless, odorless but poisonous combustible gas. It is produced in the incomplete combustion of carbon and carbon compounds such as fossil fuels (i.e., coal and petroleum) and their products (e.g., liquefied petroleum gas and gasoline) and biomass.


Carbon dioxide is a colorless, odorless gas that is produced when animals (including humans) breathe or when carbon-containing materials (including fossil fuels) are burned.

coal-bed methane:

In general terms, coal-bed gas is formed by biochemical and physical processes during the conversion of plant material into coal. Methane accounts for most of the gases created during the conversion process, and the term “coal-bed methane” has been used by industry for gas from this source. Coal-bed methane is similar to conventional natural gas but is produced from low-pressure underground coal formations rather than from underground sandstone or carbonate rock formations. It is mainly composed of methane but, like other conventional natural gases, it may contain very small quantities of other paraffin series hydrocarbons such as ethane and propane. Coal-bed methane has been referred to as a sweet gas because it typically contains very few impurities such as hydrogen sulfide and carbon dioxide normally found in natural gas. In some cases, it can be input directly into natural gas pipelines or other gathering systems with little processing. However, in other cases, the few impurities present must be removed before being input into a gathering system.

coal preparation:

The treatment of coal to reject waste. In its broadest sense, preparation is any processing of mined coal to prepare it for market, including crushing and screening or sieving the coal to reach a uniform size, which normally results in removal of some noncoal material. The term “coal preparation” most commonly refers to processing, including crushing and screening, passing the material through one or more processes to remove impurities, sizing the product, and loading it for shipment. Many of the processes separate rock, clay, and other minerals from coal in a liquid medium; hence the term “washing” is widely used. In some cases, coal passes through a drying step before loading.

combined cycle:

An electric generating technology in which electricity is produced from otherwise lost waste heat exiting from one or more gas (combustion) turbines. The exiting heat is routed to a conventional boiler or to a heat-recovery steam generator for utilization by a steam turbine in the production of electricity. Such designs increase the efficiency of the electric generating unit.

combustion turbine:

A gas turbine is a heat engine that uses high-temperature, high-pressure gas as the working fluid. Part of the heat supplied by the gas is converted directly

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