The practice of installing blow-in, loose-fill insulation at a lower density than is recommended to meet a specified R-Value.

The process of distilling (purifying) water using solar energy. Water can be placed in an air tight solar collector with a sloped glazing material, and as it heats and evaporates, distilled water condenses on the collector glazing, and runs down where it ...

The ratio of heat produced by a fuel for doing work to the available heat in the fuel.

The generation of electric power by a heat engine which converts part of the heat generated by combustion of the fuel into mechanical motion to operate an electric generator.

The time of the day, at a specific location, when the sun reaches its highest, apparent point in the sky; equal to true or due, geographic south.

An electrical conductor/cable that carries electricity from a generator to other locations for distribution.

The heat produced by sources of heat in a building (occupants, appliances, lighting, etc).

A curve illustrating the variation or spectral irradiance with wavelength.

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.

The current flowing freely through an external circuit that has no load or resistance; the maximum current possible.

The angle between a line from a point on the earth's surface to the center of the solar disc, and a line extending horizontally from the point.

A construction element applied to the outermost surface of an exterior wall.

A term used for materials used to absorb and store solar energy.

Solar radiation that arrives in a straight line from the sun.

A registered trademark for plastic sheeting material that can be used as a vapor retarder. This plastic is used to make grocery bags. It is a long chain of carbon atoms with 2 hydrogen atoms attached to each carbon atom.

Electromagnetic energy transmitted from the sun (solar radiation). The amount that reaches the earth is equal to one billionth of total solar energy generated, or the equivalent of about 420 trillion kilowatt-hours.

A type of furnace or reactor in which fuel particles are combusted while suspended in a stream of hot gas.

A device for transforming the quality and quantity of electrical energy; also an inverter.

An interior or exterior movable panel that operates on hinges or slides into place, used to protect windows or provide privacy.

Energy available due to position.