Climate Change & Energy
Glossary
Base year: A targeted year for reduction of greenhouse gas emissions. In the Kyoto Protocol, 1990 is the base year for most countries and is the base year used by Montana.
Best Practice Management (BPM): A practice, or set of practices, found to be most effective from an economic and/or institutional perspective.
Black Carbon Aerosols: Particles of carbon in the atmosphere typically produced by inefficient combustion of fossil fuels or biomass. Black carbon aerosols absorb light from the sun, shade and cool the Earth’s surface, and are believed to generally contribute to atmospheric warming of the atmosphere.
Bottled gas (LPG, or Propane): Any fuel gas supplied liquid form, such as liquefied petroleum gas, propane, or butane. It is usually delivered by tank truck and stored in a tank or cylinder until used.
British Thermal Unit (BTU): The amount of heat required to raise the temperature of one pound of water one degree Farenheit. One cubic foot of natural gas contains about 1,000 BTUs.
Carbon dioxide (CO2): A colorless, odorless, non-poisonous gas that is a normal part of ambient and atmospheric air. The main one of six gases generally agreed to be greenhouse gases. Human activities such as fossil fuel combustion and land use changes have increased atmospheric concentrations of CO2. Carbon dioxide is the standard used to measure other greenhouse gases, and is expressed as CO2-equivalent.
Carbon sink: Natural processes that remove more carbon dioxide from the atmosphere than they release over a given period of time. Terrestrial carbon sinks include forest biomasses, rangeland, and certain agricultural acreages. The oceans are also carbon sinks.
Chlorofluorocarbons (CFCs): CFCs are synthetic industrial gases composed of chlorine, fluorine, and carbon. They have been used as refrigerants, aerosol propellants, cleaning solvents and in the manufacture of plastic foam. There are no natural sources of CFCs. CFCs may last decades to centuries in the atmosphere and have been assigned a high global warming potential, much higher than that of CO2. For modeling and forecasting purposes, CFCs are converted into their CO2-equivalents.
Classes of Service: Customers grouped by similar characteristics in order to be identified for the purpose of setting a common rate for electric service. Usually classified into groups identified as residential, commercial, industrial, and other.
Climate Change: This general term refers to changes in long-term trends in the average climate, such as changes in average temperatures. For this website, climate change refers to any change in climate over time, whether due to natural variability or as a result of human activity.
Coal: A combustible black or brownish-black rock composed of carbonaceous material. It is formed from plant remains that have been compacted, hardened, chemically altered, and metamorphosed by heat and pressure over geologic time.
Coal bed: A bed or stratum of coal. Also called a coal seam.
Coal bed methane: Methane – the principal component of natural gas – is generated during coal formation and is contained in its microstructure. Recovery of the gas generally entails pumping water out of the coal to allow the gas to escape. Coal bed methane may be added to natural gas distribution pipelines, usually without further special treatment.
Coal gasification: A process that converts coal into gas. The basic process involves crushing coal to a powder, which is then heated in the presence of steam and oxygen to produce a gas. The gas is then refined to reduce sulfur and other impurities. The gas can be used as a fuel or processed further and concentrated into chemical or liquid fuel.
Cogeneration: A common energy source is used to produce both electricity and steam for other uses, resulting in increased fuel efficiency.
Dekatherm (dkt): The equivalent of one million BTUs. Natural gas is measured in thousand cubic feet (Mcf). One Mcf equals 1.03 dkt.
Combined heat and power (CHP) plant: A plant designed to produce both heat and electricity from a single heat source. This term replaces “cogenerator” to better describe facilities that do not produce heat and power in a sequential fashion.
Commercial building: A building with more than 50 percent of its floor space used for commercial activities. For this website, commercial buildings include: stores, offices, hospitals and clinics, wholesale and other warehouses. Government buildings are classified elsewhere.
Commercial sector: Within this website, an energy-consuming sector that consists of service-providing facilities and equipment of businesses and other private organizations. Government and institutional structures are classified elsewhere. Common uses of energy associated with this sector include space heating, water heating, lighting, refrigeration, cooking, and running a wide variety of equipment.
Compact fluorescent bulbs: These are also known as “low-energy replacements for incandescent.” Compact fluorescent bulbs combine the efficiency of fluorescent lighting with the convenience of a standard incandescent bulb. There are many styles of compact fluorescent, including exit light fixtures and floodlights (lamps containing reflectors). Many screw into a standard light socket, and most produce a similar color of light as a standard incandescent bulb. Compact fluorescent bulbs are designed for residential and certain commercial uses.
Construction: A subsector of the industrial sector that consists of all facilities and equipment used to perform land preparation and construct, renovate, alter, install, maintain, or repair major infrastructure or individual systems therein.
Cubic foot (cf), natural gas: The amount of natural gas contained at standard temperature and pressure (60 degrees Fahrenheit and 14.73 pounds standard per square inch) in a cube whose edges are one foot long.
Current (electric): A flow of electrons through an electrical conductor. The strength or rate of movement of the electricity is measured in amperes.
Decatherm: Ten therms or one million BTUs.
Delivered cost: The cost of an energy source including transportation charges, taxes, commissions, insurance, and expenses associated with leased or owned equipment used to transport the energy.
Demand-side management (DSM): The planning, implementation, and monitoring of energy activities designed to encourage consumers to modify patterns of energy usage, particularly the timing and level of electricity demand. It generally refers to energy modifying activities undertaken in response to utility or other organization-administered programs.
Distribution: The delivery of energy to retail customers.
Discount rate: The interest rate used to convert future payments into present values.
Electric system loss: Total energy loss from all causes for an electric utility.
Electric utility: Any entity that generates, transmits, or distributes electricity and recovers the cost of its generation, transmission or distribution assets and operations, either directly or indirectly, through cost-based rates set by a separate regulatory authority (e.g., Montana Public Service Commission). Examples may be investor-owned entities, public utility districts, rural electric cooperatives, or federal agencies.
Emissions: The release of substances (e.g., greenhouse gases) into the atmosphere.
Emissions trading: A market where countries, companies or facilities can buy emissions from or sell emissions to other emitters. Emissions trading may lower the cost of meeting emission targets. Some entities may achieve reductions at a comparatively low cost, for example. Reductions below a given level could then be sold on a world market to those for whom achieving reductions is more costly.
Energy audit: A program carried out by a utility company or other organization in which an inspection of a home or business is performed and suggestions made to conserve energy.
Energy efficiency: The reduction of energy used through specific actions or devices and systems, typically without affecting the services provided. Savings are generally achieved by substituting technologically more advanced equipment to produce the same level of end-use services (e.g., lighting, heating, motors) with less energy. Examples include high-efficiency appliances, efficient lighting programs, high-efficiency heating, ventilating and air conditioning (HVAC) systems or control modifications, efficient building design, and heat recovery systems.
Energy Star: This is a joint certification program of the U.S. Environmental Protection Agency (EPA) and the Department of Energy (DOE). Energy Star was originally a voluntary labeling program designed to identify and promote energy-efficient products to reduce greenhouse gas emissions. Computers and monitors were the first labeled products. Certification has grown more stringent as the program broadened into appliances and building technologies. According to the government website, businesses, residences, and organizations saved more than $14 billion in energy costs through the program in 2006.
Energy supplier: Any energy companies supplying electricity, natural gas, fuel oil, kerosene, or LPG (liquefied petroleum gas) to a household or business.
Energy-use sectors: Major energy-consuming components of the Montana economy. The sectors most commonly referenced on this website are: Residential, commercial, industrial, and institutional. The residential component includes commercial rentals for housing. Transportation is addressed separately, although some of its auxiliary services are accounted for in the commercial sector. Agriculture is also treated separately, although many of its energy uses are absorbed within the commercial and institutional sectors.
Fahrenheit: A temperature scale on which the boiling point of water is at 212 degrees above zero on the scale and the freezing point is at 32 degrees above zero at standard atmospheric pressure.
Firm power: Power or power-producing capacity, intended to be available at all times during a commitment period.
Floor space: The area enclosed by exterior walls of a building – often commercial structures – including parking areas, basements, or other floors below ground level. It is measured in square feet.
Flue: An enclosed passageway to direct products of combustion to the atmosphere. It may be an industrial-sized stack or a small-diameter vent from a household gas water heater.
Fossil fuel: Any naturally occurring organic fuel formed in the Earth’s crust, such as coal, crude oil, and natural gas.
Gigawatt-hour: One billion kilowatt-hours. The residential sector in Montana uses approximately 4 gigawatt-hours of electricity per year.
Greenhouse gas (GHG): Any of a variety of gases known to be transparent to incoming solar radiation but capable of absorbing reflected infrared radiation from the Earth’s surface. The principal greenhouse gases are carbon dioxide (CO2), methane, and chlorofluorocarbons, among others. Greenhouse gases other than CO2 or often converted into CO2-equivalents.
Heating Degree-Day: This is an index to show the energy demand required for space heating purposes. Averaged regional weather over the space heating season is compared against a base indoor temperature, established for the zone of common human comfort – usually 65 degrees Farenheit. The difference between the averaged outdoor temperature and the base is a heating degree-day. Consequently, areas with extreme cold temperatures have higher numbers of heating degree-days. The degree-day measurements can be used to describe the effect of outdoor temperature on the amount of energy needed for space heating, and is also useful to climatologists. Montana has about 8,400 heating degree-days, third in the contiguous states behind Minnesota and Wyoming. For more information, see the Energize Montana website.
Heat pump (geothermal or air): A heat pump exchanges heat (in a heat exchanger) with a fluid circulating through earth (geothermal) or air. Typically, a variety of piped loop configurations are buried in the comparatively warmer ground. Air systems exchange heat from outdoor air. Heat pumps can improve energy efficiency and reduce greenhouse gases in some settings.
High-intensity discharge (HID) lamp: A lamp that produces light by passing electricity through gas, which causes the gas to glow. Examples of HID lamps are mercury vapor lamps, metal halide lamps, and high-pressure sodium lamps. These lamps have extremely long life and emit far more lumens per fixture than do fluorescent lights.
HVAC: An abbreviation for the heating, ventilation, and air-conditioning; the system or systems that condition air in a building.
Hydro-electric power: The use of flowing water to turn electricity-producing turbines.
Incandescent light: A vacuum enclosed bulb which produces light when a tungsten filament is electrically heated to glowing. Much of the energy is converted into heat; therefore, this class of lamp is a relatively inefficient. Included in this category are the familiar screw-in light bulbs, as well as somewhat more efficient lamps, such as tungsten halogen lamps, reflector or r-lamps, parabolic aluminized reflector (PAR) lamps, and ellipsoidal reflector (ER) lamps.
Incentives (demand-side management): Monetary or non-monetary assistance to encourage consumers to buy energy-efficient equipment and to participate in programs designed to reduce energy usage. Examples of incentives are zero or low-interest loans, rebates, and direct installation of low cost measures, such as water heater wraps.
Insulation: Any material or substance that provides a high resistance to the flow of heat from one surface to another (expressed as R-value). The different types include blanket or batt, foam, or loose fill, which are used to reduce heat transfer by conduction. Dead air space is an insulating medium in storm windows as it reduces passage of heat through conduction and convection. Reflective materials are used to reduce heat transfer by radiation.
Intergovernmental Panel on Climate Change (IPCC): The IPCC was established in 1988 by the World Meteorological Organization and the UN. The IPCC provides scientific and technical services to the United Nations Framework Convention on Climate Change (UNFCC). The panel reviews research and publishes periodic assessment reports.
Intermittent electric generation: Any generating plant with output controlled by the natural variability of the resource, such as solar energy, wind energy.
Interruptible load: A demand-side management category. In accordance with contractual arrangements, power can be interrupted at a time of peak load, typically by the consumer, upon request of the supplier. Presently, this type of control usually involves large-volume commercial and industrial consumers.
Kilowatt-hour (kWh): The smallest common unit of the measurement of electricity. It represents a unit of energy output of 1,000 watts over one hour.
Lighting (demand-side management): An energy saving strategy designed to promote efficient lighting systems in new construction and existing homes and commercial facilities. Lighting DSM programs can include: certain types of high-efficiency fluorescent fixtures, including T-8 lamp technology, solid state electronic ballasts, specular reflectors, compact fluorescent fixtures, LED and electro-luminescent Emergency Exit Signs, High Pressure Sodium with switchable ballasts, compact metal halide, occupancy sensors, and daylighting controllers.
LIHEAP (Low-Income Home Energy Assistance Program): The purpose of LIHEAP is to assist eligible households to meet the cost of heating in residential dwellings. The federal government provides the funds to Montana for administration.
Load (electric): The amount of electric power delivered or required at any specific point or points on a system. The requirement originates at the energy-consuming equipment of the consumers.
Load control program: A program in which the utility company offers a lower rate in return for having permission to turn off a water heater or other appliance for short periods of time by remote control. This control allows the utility to reduce peak demand. The program is not currently authorized for residential customers in Montana but may be a future component of demand-side management.
Low E glass: Low-emission glass reflects up to 90 percent of long-wave radiation, which is heat, but lets in short-wave radiation, which is light. Windows are glazed with a coating that bonds a microscopic, transparent, metallic substance to the inside surface of double-pane or triple-pane windows.
Low flow showerheads: Reduce the amount of water flow through the showerhead from 5 to 6 gallons per minute to 3 gallons per minute.
Megawatt-hour (MWh): A unit of energy representing 1,000 kilowatt-hours. One MWh is produced when a 1 megawatt generator runs for one hour.
Natural gas: Hydrocarbon gases – principally methane with varying quantities of ethane, propane, butane, and other gases – that occur with petroleum deposits. Natural gas is used as a fuel in Montana for residential space and water heating. The gas is purified and delivered as a pressurized product in pipelines.
Nitrous oxide (N2O): Nitrous oxide is among six greenhouse gases identified under the Kyoto Protocol. It is produced by natural processes, but substantial emissions stem from human activities such as agriculture and fossil fuel combustion. For modeling and forecasting purposes, nitrous oxide is usually converted and expressed as CO2-equivalent.
Perfluorocarbons (PFCs): PFCs are among six types of greenhouse gases identified by the Kyoto Protocol. These are synthetic industrial gases generated as a by-product of aluminum smelting and uranium enrichment. They also are used as substitutes for CFCs in the manufacture of semiconductors. There are no natural sources of PFCs. For modeling and forecasting purposes, PFCs are usually converted and expressed as CO2-equivalent.
Renewable energy: Energy obtained from essentially inexhaustible sources. Usual sources include solar power, wind power, hydro-power, and geothermal power. Wood harvested directly from trees, tree bark, and wood waste is usually considered a combustible source. Sequestration: The removal of CO2, either through biological processes (e.g., plants and trees), or by geological processes through storage of CO2 in underground reservoirs (e.g., salt domes, limestone deposits). Certain biological sequestration strategies assume the CO2 will be stored for at least 100 years, such as in forest fibers and in geological formations. Some biological sequestration approaches capture carbon over relatively short periods of time but cycle the carbon quickly as well. Geological strategies may involve concentration, compression, and transportation of the CO2.
Sink: See Carbon Sink.
Sulfur Dioxide (SO2): A gas formed by the combustion of fuels containing sulfur--primarily coal and oil. Sulfur dioxide combines with water and oxygen in the atmosphere to form acid rain, particularly in the eastern part of the US. Montana coal is relatively low in sulfur content and a large quantity is shipped to the Midwest and elsewhere because of these properties. Cap-and-trade strategies have been successful over recent decades to lower SO2 emissions in the U.S.
Tar Sands: Sedimentary rock containing heavy oil. This type of oil cannot usually be extracted or processed by conventional petroleum recovery methods. Produced in northern Alberta.
Therm: One hundred thousand (100,000) British thermal units (1 therm = 100,000 Btu).
Thermostat setback: A timer device that can automatically adjust room temperature according to a preset schedule. The heating (or cooling) requirements can be reduced when a room or zone is unoccupied or when occupants are asleep. Energy Star units are available.
Time-of-use rates: A pricing structure for electricity based on the estimated cost of electricity during a particular block of time. Time-of-use rates are usually divided into three or four time blocks per twenty-four hour period (on-peak, mid-peak, off-peak) and by seasons of the year (summer and winter). This structure is not presently used for residential delivery in Montana.
Time-of-use meter: An electrical measuring device that records the times during which a customer uses various amounts of electricity. This type of meter is used for customers who pay time-of-use rates. This structure is not presently used for residential delivery in Montana.
Time-of-use rates: Electricity prices that vary depending on the time periods in which the energy is consumed. In a time-of- use rate structure, higher prices are charged during utility peak-load times. Such rates can provide an incentive for consumers to curb power use during peak times.
Transmission Charges: A part of the basic service charges on every customer’s bill for transporting electricity from the source of supply to the electric distribution company.
Turbine: An electrical generating device that uses steam, heated gases, water flow, or wind to spin-activate electromagnets. The force generates electricity.
Upstream: In the petroleum industry, a term referring to the exploration and production of oil. This includes collection and distribution pipelines ahead of the refining process.
Utility: A regulated entity due to monopolistic business characteristics. In electricity distribution in Montana, the term refers to the regulated operator of the transmission system only.
Volt: A unit of electromotive force required to drive a steady current of one ampere through a resistance of one ohm. Electrical systems of most homes and offices are 120 volts.
Watt: The smallest practical measure of electric power, either in a capacity or demand. One-thousandth of a kilowatt. Some Christmas tree lights use one watt. Named for Scottish inventor James Watt.
