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

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.

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.

A measure of the efficiency of converting a fuel to energy and useful work; useful work and energy output divided by higher heating value of input fuel times 100 (for percent).

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

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.

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

A house built using passive solar design techniques.

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 ...

A unit or measure of solar radiation; 1 calorie per square meter or 3.69 Btu per square foot.

The total amount of electric energy loss in an electric system between the generation source and points of delivery.

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 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.

The rate of flow of the wind undisturbed by obstacles.

The rate of heat flow required to maintain a specific indoor temperature; usually measured in Btu per hour.

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 ...

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

A type of cooling system that uses a charging and discharging cycle with a thermal or latent heat storage subsystem.

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

Material such as brick, rock, or stone.