Energy terms starting with R

153 terms

R-Factor See R-Value.
R-Value A measure of the capacity of a material to resist heat transfer. The R-Value is the reciprocal of the conductivity of a material (U-Value).
Radiant Barrier A thin, reflective foil sheet that exhibits low radiant energy transmission and under certain conditions can block radiant heat transfer; installed in…
Radiant Ceiling Panels Ceiling panels that contain electric resistance heating elements embedded within them to provide radiant heat to a room.
Radiant Energy Energy that transmits away from its source in all directions.
Radiant Floor A type of radiant heating system where the building floor contains channels or tubes through which hot fluids such as air or water are circulated.
Radiant Heating System A heating system where heat is supplied (radiated) into a room by means of heated surfaces, such as electric resistance elements, hot water (hydronic)…
Radiation (RAY-dee-AY-shun) Energy released in the form of particle or electromagnetic waves.
Radiative Cooling The process of cooling by which a heat absorbing media absorbs heat from one source and radiates the heat away.
Radiator A room heat delivery (or exchanger) component of a hydronic (hot water or steam) heating system; hot water or steam is delivered to it by natural…
Radiator Vent A device that releases pressure within a radiator when the pressure inside exceeds the operating limits of the vent.
Radioactive Waste Materials left over from making nuclear energy. Radioactive waste can living organisms if it is not stored safely.
Radon A toxic gas found in the soil beneath a house that can contribute to cancer and other illnesses.
Rafter A construction element used for ceiling support.
Rain shadow effect The region on the lee (sheltered) side of a mountain or mountain range where the precipitation is noticeably less than on the windward side, because the…
Rammed Earth A construction material made by compressing earth in a form; used traditionally in many areas of the world and widely throughout North Africa and the…
Ramp rate The rate at power system load or generator output varies, or the limits to such rates due to mechanical or reliability considerations.
Rangeland Land on which the native vegetation, climax, or natural potential consists predominately of grasses, grasslike plants, forbs, or shrubs.
Rankine Cycle The thermodynamic cycle that is an ideal standard for comparing performance of heat-engines, steam power plants, steam turbines, and heat pump systems…
Rankine steam cycle The thermodynamic cycle of temperature and pressure changes of water as it is converted from a liquid to a gaseous state by heating, and returns back to…
RAPTOR A bird of prey such as a falcon, hawk, or eagle.
Rare species See Special status species
Rate Schedule A mechanism used by electric utilities to determine prices for electricity; typically defines rates according to amounts of power demanded/consumed during…
Rated battery capacity The term used by battery manufacturers to indicate the maximum amount of energy that can be withdrawn from a battery under specified discharge rate and…
Rated Life The length of time that a product or appliance is expected to meet a certain level of performance under nominal operating conditions; in a luminaire, the…
Rated Power The power output of a device under specific or nominal operating conditions.
Rayleigh Frequency Distribution A mathematical representation of the frequency or ratio that specific wind speeds occur within a specified time interval.
reaction A chemical reaction is a dissociation, recombination, or rearrangement of atoms.
Reactive Power The electrical power that oscillates between the magnetic field of an inductor and the electrical field of a capacitor.
Real Price The unit price of a good or service estimated from some base year in order to provide a consistent means of comparison.
Real-time market An electricity market that settles–determines the price–for one-hour periods or less during the day of delivery.
Real-time pricing The instantaneous pricing of electricity based on the cost of the electricity available for use at the time the electricity is demanded by the customer.
Rebound (of water levels) The recovery/rise of the water level in a groundwater aquifer after groundwater pumping has ceased.
Receiver The component of a central receiver solar thermal system where reflected solar energy is absorbed and converted to thermal energy.
Receiving District An overlay zoning district established by the Town Meeting/ Town Council upon recommendation from the Planning Board as an area suitable to receive…
receptor (reh-SEP-ter) A molecule inside or on the surface of a cell that binds to a specific substance and causes a specific physiologic effect in the cell.
Recharge Water that infiltrates into the ground, usually from above, that replenishes groundwater reserves, provides soil moisture, and affords evapotranspiration.
Recirculated Air Air that is returned from a heated or cooled space, reconditioned and/or cleaned, and returned to the space.
Recirculation Returning a fraction of the effluent outflow to the inlet to dilute incoming wastewater.
Recirculation Systems A type of solar heating system that circulate warm water from storage through the collectors and exposed piping whenever freezing conditions occur…
Reclamation The process of restoring surface environment to acceptable pre-existing conditions.
Reclamation withdrawal Withholding an area of public land from the operation of the public land laws for the purpose of reserving the land for the use of the Bureau of…
recombinant DNA The process of cutting and recombining DNA fragments from different sources as a means to isolate genes or to alter their structure and function.
Record of Decision (ROD) The Record of Decision (ROD) is a public document that explains which cleanup alternatives will be used to clean up a Superfund site.
Recovery boiler A pulp mill boiler in which lignin and spent cooking liquor (black liquor) is burned to generate steam.
Rectifier An electrical device for converting alternating current to direct current. The chamber in a cooling device where water is separated from the working fluid…
Recuperator A heat exchanger in which heat is recovered from the products of combustion.
Recurrent Costs Costs that are repetitive and occur when an organization produces similar goods or services on a continuing basis.
Recycling The process of converting materials that are no longer useful as designed or intended into a new product.
Reference price The settlement price of a derivatives contract, based on a particular location and commodity; An estimated electricity offer price based on operating and…
Reflectance The amount (percent) of light that is reflected by a surface relative to the amount that strikes it.
Reflective Coatings Materials with various qualities that are applied to glass windows before installation.
Reflective Glass A window glass that has been coated with a reflective film and is useful in controlling solar heat gain during the summer.
Reflective Insulation (see also radiant barrier) An aluminum foil fabricated insulator with backings applied to provide a series of closed air spaces with highly reflective surfaces.
Reflective Window Films A material applied to window panes that controls heat gain and loss, reduces glare, minimizes fabric fading, and provides privacy.
Reflector A component of a solar energy facility that reflects incident sunlight to a desired location or component within the facility, allowing it to be converted…
Reflector Lamps A type of incandescent lamp with an interior coating of aluminum that reflects light to the front of the bulb.
Reformulated gasoline (RFG) Gasoline that has altered composition or characteristics to reduce emissions of pollutants from vehicles in accordance with the Clean Air Act.
Refraction The change in direction of a ray of light when it passes through one media to another with differing optical densities.
Refractory Lining A lining, usually of ceramic, capable of resisting and maintaining high temperatures.
Refrigerant The compound (working fluid) used in air conditioners, heat pumps, and refrigerators to transfer heat into or out of an interior space.
Refrigeration The process of the absorption of heat from one location and its transfer to another for rejection or recuperation.
Refrigeration Capacity A measure of the effective cooling capacity of a refrigerator, expressed in Btu per hour or in tons, where one (1) ton of capacity is equal to the heat…
Refrigeration Cycle The complete cycle of stages (evaporation and condensation) of refrigeration or of the refrigerant.
Refuse-Derived Fuel (RDF) A solid fuel produced by shredding municipal solid waste (MSW). Noncombustible materials such as glass and metals are generally removed prior to making…
Regeneration harvest A timber harvest method that removes selected trees in the existing stand to a density that allows for the establishment of a new even-aged stand below.
Regeneration with reserves Similar to a regeneration harvest, except that a number of green trees are left standing to meet other resource needs such as wildlife habitat.
Regenerative Braking A feature of hybrid and plug-in electric vehicles that captures energy normally lost during braking by using the electric motor as a generator and storing…
Regenerative Cooling A type of cooling system that uses a charging and discharging cycle with a thermal or latent heat storage subsystem.
Regenerative Heating The process of using heat that is rejected in one part of a cycle for another function or in another part of the cycle.
Region of Influence (ROI) Area occupied by affected resources and the distances at which impacts associated with license renewal may occur.
Regional Transmission Organization (RTO) A voluntary organization of electric transmission owners, transmission users and other entities approved by the Commission to efficiently coordinate…
Regular-track proposals Proposals on public land with pending applications considered as potential future projects, but not necessarily foreseeable projects, since not all…
Rehabilitation Any repair work that requires a permit.
Reid vapor pressure (RVP) A standard measurement of a liquid´s vapor pressure at 100 degrees Fahrenheit. An indication of the propensity of the liquid to evaporate.
Reinjection The feeding of unburned char and fly ash obtained from mechanical collectors into the furnace for further combustion.
Relamping The replacement of a non-functional or ineffective lamp with a new, more efficient lamp.
Relative Humidity A measure of the percent of moisture actually in the air compared with what would be in it if it were fully saturated at that temperature.
Reliability The consistency of a measure or question in obtaining very similar or identical results when used repeatedly; for example, if you repeated a blood test…
Reliability must run (RMR) A unit that must run for operational or reliability reasons, regardless of economic considerations. Also called a reliability agreement.
Relict A land surface that was once a basin (valley) floor.
Renewable Energy Energy derived from resources that are regenerative or for all practical purposes can not be depleted.
Renewable Energy Certificate (REC) A tradable certificate representing the generation attributes of energy derived from a qualified renewable energy source. In the U.S.
renewable energy resource An energy resource that can be replaced as it is used. Renewable energy resources include solar, wind, geothermal, hydro, and biomass.
Renewable energy source An energy source that is replenished continuously in nature or that is replaced after use through natural means. Sustainable energy source.
Renewable Fuels Standard A regulation created under the Energy Policy Act of 2005 and implemented by the U.S.
Renewable Resource Generation Development Area (GDA) Regions within Colorado with a concentration of renewable resources that provide a minimum of 1,000 MW of developable electric generating capacity.
Repetition/replication There are four plots in a repetition/replication, the early, mid and late seral treatment plots and a control plot.
Reptile Cold-blooded vertebrate of the class Reptilia whose skin is usually covered in scales or scutes.
Reserve margin The percentage of installed capacity exceeding the expected peak demand during a specified period.
Reserved Water Right A special water right accompanying federal lands (military reservations, national parks, forests, or monuments) or Indian reservations.
Reservoir A reservoir of an infectious agent, such as a virus, is any animal, person, plant, soil, substance—or combination of any of these — in which the…
Resident fish Fish species that complete their entire life cycle in freshwater. Non-anadromous fish. An example is rainbow trout.
Residential Site Improvement Standards (RSIS) Development rules (disseminated by DCA) that delineate infrastructure requirements for new residential areas.
Residual fuel oil Heavy fuel oil produced from the residue in the fractional distillation process rather than from the distilled fractions. No.
residues, biomass Byproducts from processing all forms of biomass that have significant energy potential.
Residuum Unconsolidated, weathered, or partly weathered mineral material that accumulates by disintegration of bedrock in place.
Resistance The ability of an organism to develop ways to be impervious to specific threats to their existence.
Resistance Heating A type of heating system that provides heat from the resistance of an electrical current flowing through a conductor.
Resistive Voltage Drop The voltage developed across a cell by the current flow through the resistance of the cell.