Energy terms starting with S

358 terms

Solenoid Valve An automatic valve that is opened or closed by an electromagnet.
Solid Fuels Any fuel that is in solid form, such as wood, peat, lignite, coal, and manufactured fuels such as pulverized coal, coke, charcoal, briquettes, pellets…
Solid waste All unwanted, abandoned, or discarded solid or semisolid material whether or not subject to decomposition, originating from any source.
Solidity In reference to a wind energy conversion device, the ratio of rotor blade surface area to the frontal, swept area that the rotor passes through.
Solstice The two times of the year when the sun is apparently farthest north and south of the earth's equator; usually occurring on or around June 21 (summer…
Solvent extraction A method of separation used to purify vegetable oils.
Source Any place or object from which air pollutants are released. Sources that are fixed in space are stationary sources and sources that move are mobile…
Source Emission Reduction Plan (SERP) A contingency plan developed to reduce emissions during an air quality emergency.
Source Water Assessment Plan (SWAP) A requirement of the 1996 amendments to the federal Safe Drinking Water Act that an assessment and protection plan be developed for each surface water…
Southwest Regional Gap Analysis Project (SWReGAP) The Southwest Regional Gap Analysis Project is an update of the Gap Analysis Program's mapping and assessment of biodiversity for the five-state region…
Space Heater A movable or fixed heater used to heat individual rooms.
Spacer (Window) Strips of material used to separate multiple panes of glass within the windows.
Spark spread The difference in price between electricity purchased from the grid and electricity generated from, for example, purchased natural gas.
Spawning gravel Sorted, clean gravel patches of a size appropriate for the needs of resident or anadromous fish.
Special areas Areas of high public interest and containing outstanding natural features or values.
Special Districts Geographic areas in which fees or taxes are collected to fund investments or services benefiting properties within the district.
Special Permit A use that would not be appropriate generally, or without restriction through the zoning district but which, if controlled as to number, area, location…
Special status species (threatened, endangered, sensitive, rare) Includes both plant and animal species that are proposed for listing, officially listed as threatened or endangered, or are candidates for listing as…
Special Use Airspace (SUA) Airspace of defined dimensions identified by an area on the surface of the Earth wherein activities must be confined because of their nature and/or…
Specially Designated Areas Includes a variety of areas that have received recognition or designation because they possess unique or important resource values.
Species of Special Concern A species that may have a declining population, limited occurrence, or low numbers for any of a variety of reasons.
Specific Heat The amount of heat required to raise a unit mass of a substance through one degree, expressed as a ratio of the amount of heat required to raise an equal…
Specific Heat Capacity The quantity of heat required to change the temperature of one unit weight of a material by one degree.
Specific Humidity The weight of water vapor, per unit weight of dry air.
Specific Volume The volume of a unit weight of a substance at a specific temperature and pressure.
Specific work work output -------------- mass flow
Spectral Energy Distribution A curve illustrating the variation or spectral irradiance with wavelength.
Spectral Irradiance The monochromatic irradiance of a surface per unit bandwidth at a particular wavelength, usually expressed in Watts per square meter-nanometer bandwidth.
Spectral Reflectance The ratio of energy reflected from a surface in a given waveband to the energy incident in that waveband.
Spectrally Selective Coatings A type of window glazing films used to block the infrared (heat) portion of the solar spectrum but admit a higher portion of visible light.
Spectrum Electromagnetic radiation arranged in order of wavelength from Ion wavelength radio waves to short wavelength gamma rays.
Specular reflection Also known as direct reflection, regular reflection, or mirror reflection. The reflection of electromagnetic rays without scattering or diffusion.
Spill light Light that falls outside of the area intended to be lighted.
Spillway A passage for surplus water to flow over or around a dam.
Spinning Reserve Electric power provider capacity on line and running at low power in excess of actual load.
Split Spectrum Photovoltaic Cell A photovoltaic device where incident sunlight is split into different spectral regions, with an optical apparatus, that are directed to individual…
Split System Air Conditioner An air conditioning system that comes in two to five pieces: one piece contains the compressor, condenser, and a fan; the others have an evaporator and a…
Spot market Commodities and foreign currencies are traded for immediate delivery and payment on the spot market, also known as a cash market.
Spotted owl habitat Dispersal habitat: Forest vegetation with at least 40% canopy closure and an average stand diameter of 11".
Sprawl Development patterns where rural land is converted to urban/suburban uses more quickly than needed to house new residents and support new businesses, and…
Spray Pyrolysis A deposition process whereby heat is used to break molecules into elemental sources that are then spray deposited on a substrate.
Spread trading Buying one instrument/commodity and selling another, with a view to profiting from the change in the gap between the two markets.
Spreader Stocker A type of furnace in which fuel is spread, automatically or mechanically, across the furnace grate.
Spreader stoker furnace A furnace in which fuel is automatically or mechanically spread. Part of the fuel is burned in suspension. Large pieces fall on a grate.
Spring The point at which the water table meets Earth's surface, causing water to flow from the ground.
Sprinkler system Consists of pipelines which carry water under pressure from a pump or elevated source to lateral lines along which sprinkler heads are spaced at…
Sputtering A process used to apply photovoltaic semi-conductor material to a substrate by a physical vapor deposition process where high-energy ions are used to…
Square Wave Inverter A type of inverter that produces square wave output.; consists of a DC source, four switches, and the load.
Squirrel Cage Motor This is another name for an induction motor. The motors consist of a rotor inside a stator.
Stack A group of 20 roulette chips.
Stack (Heat) Loss Sensible and latent heat contained in combustion gases and vapor emitted to the atmosphere.
Staebler-Wronski effect The tendency of the sunlight to electricity conversion efficiency of amorphous silicon photovoltaic devices to degrade (drop) upon initial exposure to…
staging area A designated area where construction equipment is temporarily stored (usually only during the construction phase).
Stagnation Temperature A condition that can occur in a solar collector if the working fluid does not circulate when sun is shining on the collector.
Stall In reference to a wind turbine, a condition when the rotor stops turning.
Stand To decline additional cards and keep your existing total.
Stand conversion The conversion of a noncommercial stand of timber to a commercial stand.
Stand density The number or mass of trees occupying a site. It is usually measured in terms of stand density index or basal area per acre.
Stand-Alone Generator A power source/generator that operates independently of or is not connected to an electric transmission and distribution network; used to meet a load(s)…
Stand-Alone Inverter An inverter that operates independent of or is not connected to an electric transmission and distribution network.
Stand-Alone System An system that operates independent of or is not connected to an electric transmission and distribution network.
Stand-by Heat Loses A term used to describe heat energy lost from a water heater tank.
Stand-By Power For the consumer, this is the electricity that is used by your TVs, stereos, and other electronic devices that use remote controls.
Standard Air Air with a weight of 0.075 pounds per cubic foot with an equivalent density of dry air at a temperature of 86 degrees Fahrenheit and standard barometric…
Standard Conditions In refrigeration, an evaporating temperature of 5 degrees Fahrenheit (F), a condensing temperature of 86 degrees F.
Standard Cubic Foot A column of gas at standard conditions of temperature and pressure (32 degrees Fahrenheit and one atmosphere).
Standard Industrial Classification (SIC) Code Standardized codes used to classify businesses by type of activity they engage in.
Standards and guidelines Bounds or constraints within which all practices in a given area will be carried out, in achieving the goals and objectives for that area.
Starting Surge Power, often above an appliance's rated wattage, required to bring any appliance with a motor up to operating speed.
Starting Torque The torque at the bottom of a speed (rpm) versus torque curve. The torque developed by the motor is a percentage of the full-load or rated torque.
State Historic Preservation Officer (SHPO) The State officer charged with the identification and protection of prehistoric and historic resources in accordance with the National Historic…
State Implementation Plan (SIP) A state plan required by the Clean Air Act to bring nonattainment areas into compliance with federal ambient air quality standards.
State Tax Incentives Massachusetts offers tax incentives to individuals and business that install renewable energy systems at their homes or offices.
Static Pressure The force per unit area acting on the surface of a solid boundary parallel to the flow.
Steam Water in vapor form; used as the working fluid in steam turbines and heating systems.
Steam amendment chemicals Chemicals used to treat raw water to remove certain chemical species, thus amending its hardness or pH, making it suitable for use in a steam cycle.
Steam Boiler A type of furnace in which fuel is burned and the heat is used to produce steam.
Steam conversion factors (approximations) 1 pound of steam = 1,000 Btu = .3 kW. 10,000 lbs/hr steam = 300 boiler horsepower.
Steam plant A plant in which the prime mover is a steam turbine. The steam used to drive the turbine is produced in a boiler where fossil fuels are burned.
Steam Turbine A device that converts high-pressure steam, produced in a boiler, into mechanical energy that can then be used to produce electricity by forcing blades in…
Steam turbine-generator (STG) A device that uses high-pressure steam, produced in a boiler, to drive the blades of a turbine to produce mechanical energy that can then be used to…
Steep slopes Ground surface that rises precipitously above the horizon.
Steppe Habitat dominated by shrubs and grasses.
STG See Steam turbine generator
Stillage The grains and liquid effluent remaining after distillation.
Stirling Engine A heat engine of the reciprocating (piston) where the working gas and a heat source are independent.
Stoichiometric condition That condition at which the proportion of the air-to-fuel is such that all combustible products will be completely burned with no oxygen remaining in the…
Stoichiometric Ratio The ratio of chemical substances necessary for a reaction to occur completely.
Stoichiometry Chemical reactions, typically associated with combustion processes; the balancing of chemical reactions by providing the exact proportions of reactant…
Stolon A lateral stem that grows horizontally along the ground surface. Used by some plant species as a mechanism for dispersal, since stolon nodes can…
Storage Capacity The amount of energy an energy storage device or system can store.
Storage Hydropower A hydropower facility that stores water in a reservoir during high-inflow periods to augment water during low-inflow periods.
Storage Tank The tank of a water heater.
Storage Water Heater A water heater that releases hot water from the top of the tank when a hot water tap is opened.
Storm Door An exterior door that protects the primary door.
Storm Windows Glass, plastic panels, or plastic sheets that reduce air infiltration and some heat loss when attached to either the interior or exterior of existing…
stover The dried stalks and leaves of a crop remaining after the grain has been harvested.
Strain A genetic variant within a species.
Stranded Investment (Costs and Benefits) An investment in a power plant or demand side management measures or programs, that become uneconomical due to increased competition in the electric power…
Strata Single, distinct layers of sediment or sedimentary rock.