The fine liquid or solid particles contained in combustion gases. The quantity and size of particulates emitted by cars, power and industrial plants, wood stoves, etc are regulated by the U.S. Environmental Protection Agency.

The electrical and magnetic fields created by the presence or flow of electricity in an electrical conductor or electricity consuming appliance or motor.

A wheel that is designed to use the weight and/or force of moving water to turn it, primarily to operate machinery or grind grain.

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

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

A power source/generator that operates independently of or is not connected to an electric transmission and distribution network; used to meet a load(s) physically close to the generator.

The amount (percent) of light that is reflected by a surface relative to the amount that strikes it.

A fluid used to absorb and transfer heat energy.

A type of cooling system that uses a charging and discharging cycle with a thermal or latent heat storage subsystem.

A device that uses electronic components to regulate the voltage of fluorescent lamps.

A structure or media from which heat can be absorbed or extracted.

The rate of energy transfer equivalent to one ampere under an electrical pressure of one volt. One watt equals 1/746 horsepower, or one joule per second. It is the product of Voltage and Current (amperage).

Energy generated from an electromagnetic field produced by an electric current flowing through a superconducting wire kept at a specific low temperature.

Fuels that cannot be easily made or "renewed," such as oil, natural gas, and coal.

A type of solar thermal collector in which a heat transfer fluid drips out of header pipe at the top of the collector, runs down the collector absorber and into a tray at the bottom where it drains to a storage tank.

A structure or media that absorbs heat.

The process of changing from one physical state (solid, liquid, or gas) to another, with a necessary or coincidental input or release of energy.

An index that combines sensible temperature and air humidity to arrive at a number that closely responds to the effective temperature; used to relate temperature and humidity to levels of comfort.

A sinusoidal quantity having a frequency that is an integral multiple of the frequency of a periodic quantity to which it is related.

Space cooling achieved by shading, natural (unassisted, as opposed to forced) ventilation, conduction control, radiation, and evaporation; also called passive cooling.