A type of insulation that is molded or expanded to produce coarse, closed cells containing air. The rigid cellular structure provides thermal and acoustical insulation, strength with low weight, and coverage with few heat loss paths. Often used to insulat ...

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

A device that converts high-pressure steam, produced in a boiler, into mechanical energy that can then be used to produce electricity by forcing blades in a cylinder to rotate and turn a generator shaft.

Strips of material used to separate multiple panes of glass within the windows.

That amount of cooling energy to be supplied (or heat and humidity removed) based on the sensible and latent loads.

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.

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 structural, insulated product with foam insulation contained between two facings of drywall, or structural wood composition boards such as plywood, waferboard, and oriented strand board.

The requirement that an electric power utility generate or purchase a specified percentage of the power it supplies/sells from renewable energy resources, and thereby guarantee a market for electricity generated from renewable energy resources.

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

The total capacity of electrical generation devices in a power station or system.

The type of alternative current generated by alternating current generators, rotary inverters, and solid-state inverters.

A glazed structure, such as greenhouse or "sunspace."

A group of solar collectors or solar modules connected together.

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 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 difference between the brightness of an object compared to that of its immediate background.

A solar thermal technology that uses a modular mirror system that approximates a parabola and incorporates two-axis tracking to focus the sunlight onto receivers located at the focal point of each dish. The mirror system typically is made from a number of ...

The amount of heat required to raise a unit mass of a substance through one degree, expressed as a ratio of the amount of heat required to raise an equal mass of water through the same range.

A value used to estimate interior air cooling requirements (load) calculated as the number of degrees per day (over a specified period) that the daily average temperature is above 65 degrees Fahrenheit (or some other, specified base temperature). The dail ...