Warranty: A seller's guarantee to purchaser that product is what it is represented to be and, if it is not, that it will be repaired or replaced. Within the context of vehicles, refers to an engine manufacturer's guarantee that the engine will meet "certified" engine standards at 50,000 miles or the engine will be replaced. Retrofits may generally void an engine warranty.
Waste Energy: Garbage, bagasse, sewerage gas, and other industrial, agricultural, and urban refuse used to generate electricity.
Water Factor (WF): WF is a measurement of water efficiency that is calculated as gallons of water used per cubic foot of capacity. So, if a clothes washer uses 30 gallons per cycle and has a tub volume of 3.0 cubic feet, then the water factor is 10.0. The lower the WF, the more efficient the clothes washer.
WF is the present water performance metric that allows the comparison of clothes washer water consumption independent of clothes washer capacity. WF is the quotient of the total weighted per-cycle water consumption, Q, divided by the capacity of the clothes washer, C. The lower the value, the more water efficient the clothes washer. The equation is: WF = Q / C. ENERGY STAR qualified clothes washers must have a maximum WF of 7.5.
Water Heater: An appliance for supplying hot water for purposes other than space heating or pool heating.
Watt: The base unit of power, a watt, is a measure of the rate at which work is being done. One watt of power maintained over time is equal to one joule per second. Some Christmas tree lights use one watt. The Watt is named after Scottish inventor James Watt and is capitalized when shortened to w and used with other abbreviations, as in kWh.
Watthour (Wh): An electrical energy unit of measure equal to one watt of power supplied to, or taken from, an electric circuit steadily for one hour. A unit of energy equivalent to one thousandth of a kilowatthour.
Waxes: Solid or semisolid materials derived from petroleum distillates or residues. Waxes are light–colored, more or less translucent crystalline masses, slightly greasy to the touch, consisting of a mixture of solid hydrocarbons in which the paraffin series predominates. Included are all marketable waxes, whether crude scale or fully refined. Waxes are used primarily as industrial coating for surface protection.
Weatherstripping: Specially designed strips, seals and gaskets installed around doors and windows to limit air leakage.
Wellhead Price: Represents the sales price, including charges for natural gas plant liquids subsequently removed from the gas, gathering and compression charges, and State production, severance and/or similar charges.
West Region: In align with the American Gas Association definition, the Energy Information Administration adopted three natural gas storage regions: the West Region, the East Region, and the Producing Region. The West Region includes the following states: Arizona, California, Colorado, Idaho, Minnesota, Montana, Nevada, North Dakota, Oregon, South Dakota, Washington, Wyoming, and Utah. Also see map.
West Texas Intermediate: West Texas Intermediate (WTI) crude oil is of very high quality and is excellent for refining a larger portion of gasoline. Its API gravity is 39.6 degrees (making it a “light” crude oil), and it contains only about 0.24 percent of sulfur (making a “sweet” crude oil). This combination of characteristics, combined with its location, makes it an ideal crude oil to be refined in the United States, the largest gasoline consuming country in the world. Most WTI crude oil gets refined in the Midwest region of the country, with some more refined within the Gulf Coast region. Although the production of WTI crude oil is on the decline, it still is the major benchmark of crude oil in the Americas. WTI is generally priced at about a $2–per–barrel premium to the OPEC basket price and about $1–per–barrel premium to Brent, although on a daily basis the pricing relationships between these can vary greatly.
Western Area Power Administration (WAPA): Western Area Power Administration markets and delivers cost-based hydroelectric power and related services within a 15-state region of the central and western U.S.
Wet–Bulb Temperature: The temperature at which water, by evaporating into air, can bring the air to saturation at the same temperature. Wet–bulb temperature is measured by a wet–bulb psychrometer.
WF: See Water Factor.
Wheeling: The transmission of electricity by an entity that does not own or directly use the power it is transmitting. Wholesale wheeling is used to indicate bulk transactions in the wholesale market, whereas retail wheeling allows power producers direct access to retail customers. This term is often used colloquially as meaning transmission.
Whole House Fan: A system capable of cooling a house by exhausting a large volume of warm air when the outside air is cool.
Wholesale Competition: A system whereby a distributor of power would have the option to buy its power from a variety of power producers, and the power producers would be able to compete to sell their power to a variety of distribution companies.
Wholesale Power Market: The purchase and sale of electricity from generators to resellers (who sell to retail customers) along with the ancillary services needed to maintain reliability and power quality at the transmission level.
Wind Energy: The kinetic energy of wind converted into mechanical energy by wind turbines (i.e., blades rotating from a hub) that drive generators to produce electricity for distribution.
Working (Top Storage) Gas (natural gas): The volume of gas in an underground storage reservoir above the designed level of the base. It may or may not be completely withdrawn during any particular withdrawal season. Conditions permitting, the total working capacity could be used more than once during any season.