A configuration of an electrical circuit in which the voltage is the same across the terminals. The positive reference direction for each resistor current is down through the resistor with the same voltage across each resistor.

This is a national organization dedicated to representing the interests of cooperative electric utilities and the consumers they serve. Members come from the 46 states that have an electric distribution cooperative.

The unit price of a good or service estimated from some base year in order to provide a consistent means of comparison.

The change in direction of a ray of light when it passes through one media to another with differing optical densities.

The ability to send or wheel electric power to a customer over a transmission and distribution system that is not owned by the generator (seller) of the power.

A device that produces mechanical energy directly from two heat reservoirs of different temperatures. A machine that converts thermal energy to mechanical energy, such as a steam engine or turbine.

A hydrocarbon gas obtained from underground sources, often in association with petroleum and coal deposits. It generally contains a high percentage of methane, varying amounts of ethane, and inert gases; used as a heating fuel.

A house built using passive solar design techniques.

An elementary particle of an atom with a negative electrical charge and a mass of 1/1837 of a proton; electrons surround the positively charged nucleus of an atom and determine the chemical properties of an atom.

A pole used to assist in raising a tower.

Any device (or plant) that follows the sun's apparent movement across the sky.

A building energy auditing technique for locating areas of low insulation in a building envelope by means of a thermographic scanner.

The electrical power that oscillates between the magnetic field of an inductor and the electrical field of a capacitor. Reactive power is never converted to non-electrical power. Calculated as the square root of the difference between the square of the ki ...

Individual rooms or zones in a building where temperature is controlled separately from other rooms or zones.

The process of characterizing the wind resource, and its energy potential, for a specific site or geographical area.

The products of all combustion processes formed by the combination of nitrogen and oxygen.

A solar water or space-heating system in which solar energy is collected, and/or moved by natural convection without using pumps or fans. Passive systems are typically integral collector/storage (ICS; or batch collectors) or thermosyphon systems. The majo ...

An aluminum foil fabricated insulator with backings applied to provide a series of closed air spaces with highly reflective surfaces.

The amount of heat in a quantity of matter at a specific temperature and pressure.

The ratio of the minimum amount of work or energy required to perform a task to the amount actually used.