A type of water heater that circulates water through a heat exchanger in a boiler. The heated water then flows into an insulated storage tank.

The thermodynamic cycle that is an ideal standard for comparing performance of heat-engines, steam power plants, steam turbines, and heat pump systems that use a condensable vapor as the working fluid; efficiency is measured as work done divided by sensib ...

A device where sunlight concentrated onto a absorber heats it to a high temperature, and the thermal radiation emitted by the absorber is used as the energy source for a photovoltaic cell that is designed to maximize conversion efficiency at the wavelengt ...

A type of motor designed to operate precisely at the synchronous speed with no slip in the full-load speeds (rpm).

The amount of useful energy produced by a system less the amount of energy required to produce the fuel.

The amount of heat introduced to a space from all heat producing sources, such as building occupants, lights, appliances, and from the environment, mainly solar energy.

A wood-burning appliance for space and/or water heating and/or cooking.

One thousand kilowatts, or 1 million watts; standard measure of electric power plant generating capacity.

The heat that flows from the building interior, through the building envelope to the outside environment.

A measure of the efficiency of converting a fuel to energy and useful work; useful work and energy output divided by higher heating value of input fuel times 100 (for percent).

An instrument for measuring solar radiation.

The unit price of a good or service estimated from some base year in order to provide a consistent means of comparison.

An elementary particle of an atom with a negative electrical charge and a mass of 1/1837 of a proton; electrons surround the positively charged nucleus of an atom and determine the chemical properties of an atom.

A type of water heater that has no storage tank thus eliminating storage tank standby losses. Cold water travels through a pipe into the unit, and either a gas burner or an electric element heats the water only when needed.

A house built using passive solar design techniques.

A configuration of an electrical circuit in which the voltage is the same across the terminals. The positive reference direction for each resistor current is down through the resistor with the same voltage across each resistor.

A hydrocarbon gas obtained from underground sources, often in association with petroleum and coal deposits. It generally contains a high percentage of methane, varying amounts of ethane, and inert gases; used as a heating fuel.

A mainly flat surface for transmitting radiant energy.

A building energy auditing technique for locating areas of low insulation in a building envelope by means of a thermographic scanner.

A solar energy conversion device that has a bowl shaped dish covered with a highly reflective surface that tracks the sun and concentrates sunlight on a fixed absorber, thereby achieving high temperatures, for process heating or to operate a heat (Stirlin ...