The regular periodic arrangement of atoms or molecules in a crystal of semiconductor material.

The trapping of light inside a semiconductor material by refracting and reflecting the light at critical angles; trapped light will travel further in the material, greatly increasing the probability of absorption and hence of producing charge carriers.

Alternating current is carried by conductors and a ground to residential, commercial, or industrial consumers. The waveform of the phase power appears as a single continuous sine wave at the system frequency whose amplitude is the rated voltage of the pow ...

The process of managing the consumption of energy, generally to optimize available and planned generation resources.

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 heating system where heat is supplied (radiated) into a room by means of heated surfaces, such as electric resistance elements, hot water (hydronic) radiators, etc.

A description of how well people in a lighted space can see to do visual tasks and how visually comfortable they feel in that space.

A device that captures the heat from the exhaust air from a building and transfers it to the supply/fresh fresh air entering the building to preheat the air and increase overall heating efficiency.

A unit of pressure for a fluid, commonly used in water pumping and hydropower to express height a pump must lift water, or the distance water falls. Total head accounts for friction head losses, etc.

States that energy cannot be created or destroyed, but only changed from one form to another. First Law efficiency measures the fraction of energy supplied to a device or process that it delivers in its output. Also called the law of conservation of energ ...

Site planning that accounts for natural solar heating and cooling processes and their relationship to building shape, orientation, and siting.

A company or individual that is not directly regulated as a utility. These entities produce power for their own use and/or sell it to regulated utilities.

The amount of solar radiation striking a surface per unit of time and area.

The transmission of electricity through power lines.

Features and vegetation on the outside of or surrounding a building for aesthetics and energy conservation.

The process of the absorption of heat from one location and its transfer to another for rejection or recuperation.

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

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

A WECS designed to produce electricity.

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 ...