A window located on the roof of a structure to provide interior building spaces with natural daylight, warmth, and ventilation.

A concrete pad that sits on gravel or crushed rock, well-compacted soil either level with the ground or above the ground.

A slab floor that sits directly on top of the surrounding ground.

A term used to describe a technologically advanced window system that contains glazing that can change or switch its optical qualities when a low voltage electrical signal is applied to it, or in response to changes in heat or light.

A type of high intensity discharge light that has the most lumens per watt of any light source.

A panel which covers the underside of an roof overhang, cantilever, or mansard.

The legal issues related to protecting or ensuring access to sunlight to operate a solar energy system, or use solar energy for heating and cooling.

A type of solar thermal system where air is heated in a collector and either transferred directly to the interior space or to a storage medium, such as a rock bin.

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 group of solar collectors or solar modules connected together.

The angle between the sun's apparent position in the sky and true south, as measured on a horizontal plane.

A solar photovoltaic device with a specified area.

A device used to collect, absorb, and transfer solar energy to a working fluid.

The average amount of solar radiation that reaches the earth's upper atmosphere on a surface perpendicular to the sun's rays; equal to 1353 Watts per square meter or 492 Btu per square foot.

The use of solar thermal energy or solar electricity to power a cooling appliance. There are five basic types of solar cooling technologies: absorption cooling, which can use solar thermal energy to vaporize the refrigerant; desiccant cooling, which can u ...

The apparent angle of the sun north or south of the eath's equatorial plane. The earth's rotation on its axis causes a daily change in the declination.

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 ...

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 national trade association of solar energy equipment manufacturers, retailers, suppliers, installers, and consultants.

A federally funded institute, created by the Solar Energy Research, Development and Demonstration Act of 1974, that conducted research and development of solar energy technologies. Became the National Renewable Energy Laboratory (NREL) in 1991.