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 process of producing electricity by transforming other forms or sources of energy into electrical energy; measured in kilowatt-hours.

A type of incandescent lamp with an interior coating of aluminum that reflects light to the front of the bulb. They are designed to spread light over specific areas.

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

A measure of the average amount of a specified pollutant or material emitted for a specific type of fuel or process.

The amount of heat that a material can absorb and store.

The amount of time required for positive cash flows to equal the total investment costs.

Thermosyphon systems use a separate storage tank located above the collector. Liquid warmed in the collector rises naturally above the collector, where it is kept until it is needed. The liquid can be either water or a glycol solution. If the fluid is wat ...

The maximum value of natural solar insolation.

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.

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.

The value of a personal portfolio, product, or investment after depreciation and interest on debt capital are subtracted from operating income. It can also be thought of as the equivalent worth of all cash flows relative to a base point called the present ...

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

A lamp where the light beam is focused 2 inches ahead of the lamp reducing the amount of light trapped in the fixture.

The process of using heat that is rejected in one part of a cycle for another function or in another part of the cycle.

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

A measure of the effective cooling capacity of a refrigerator, expressed in Btu per hour or in tons, where one (1) ton of capacity is equal to the heat required to melt 2,000 pounds of ice in 24 hours or 12,000 Btu per hour.

A corporation, person, agency, authority or other legal entity that owns and/or operates facilities for the generation, transmission, distribution or sale of electricity primarily for use by the public.

Material such as brick, rock, or stone.

A solar energy concentrating technology that uses a linear receiver that tracks the focal area of a reflector or array of reflectors.