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

As a component of a heating or cooling appliance, rows of tubing or pipe with fins attached through which a heat transfer fluid is circulated and to deliver heat or cooling energy to a building.

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

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).

The loss of heat as the water circulates through a water heater tank and inlet and outlet pipes.

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

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

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.

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

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

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

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

As time increases from zero at the terminals of an inductor, the voltage comes to a particular value on the sine function curve ahead of the current. The voltage reaches its negative peak exactly 90 degrees before the current reaches its negative peak thu ...

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

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

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

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

The load created by moisture in the air, including from outside air infiltration and that from indoor sources such as occupants, plants, cooking, showering, etc.

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.

A construction material made by compressing earth in a form; used traditionally in many areas of the world and widely throughout North Africa and the Middle East.