A device that can be set to automatically turn appliances (lights) off and on at set times.

Materials left over from making nuclear energy. Radioactive waste can living organisms if it is not stored safely.

The maximum energy demand or load in a specified time period.

A heat exchanger in which heat is recovered from the products of combustion.

A measure of the percent of moisture actually in the air compared with what would be in it if it were fully saturated at that temperature. When the air is fully saturated, its relative humidity is 100 percent.

Energy that comes from splitting atoms of radioactive materials, such as uranium, and which produces radioactive wastes.

A type of solar heating system that circulate warm water from storage through the collectors and exposed piping whenever freezing conditions occur; obviously a not very efficient system when operating in this mode.

An electrical device for converting alternating current to direct current. The chamber in a cooling device where water is separated from the working fluid (for example ammonia).

This law states that no device can completely and continuously transform all of the energy supplied to it into useful energy.

A study of the transformation of energy from one form to another, and its practical application. (see Law(s) of Thermodynamics above).

A material with high absorbtance and low emittance properties applied to or on solar absorber surfaces.

A solar absorber surface that has high absorbtance at wavelengths corresponding to that of the solar spectrum and low emittance in the infrared range.

A building element that shades windows, walls, and doors from direct solar radiation and protects these elements from precipitation.

Wood, used for fuel, that has been air dried so that it contains 15 to 20 percent moisture content (wet basis).

A solar thermal system that has one tank for storing solar heated water to preheat the water in a conventional water heater.

Power generation equipment or system capacity to meet peak power demands.

These fluids can be either water or steam trapped in fractured or porous rocks; they are found from several hundred feet to several miles below the Earth's surface. The temperatures vary from about 90 F to 680 F (32 C to 360 C) but roughly 2/3 range in te ...

The labels placed on appliances to enable consumers to compare appliance energy efficiency and energy consumption under specified test conditions as required by the Federal Trade Commission.

The complete cycle of stages (evaporation and condensation) of refrigeration or of the refrigerant.

A term generally applied to individual solar collectors, and typically to solar photovoltaic collectors or modules.