A hard, dense type of coal, that is hard to break, clean to handle, difficult to ignite, and that burns with an intense flame and with the virtual absence of smoke because it contains a high percentage of fixed carbon and a low percentage of volatile matt ...

Referring to alterations in the environment due to the presence or activities of humans.

A fluid, such as methanol or ethylene glycol, added to vehicle engine coolant, or used in solar heating system heat transfer fluids, to protect the systems from freezing.

A thin coating of a material applied to a photovoltaic cell surface that reduces the light reflection and increases light transmission.

An opening; in solar collectors, the area through which solar radiation is admitted and directed to the absorber.

A solar day; an interval between successive transits of the sun's center across an observer's meridian; the time thus measured is not equal to clock time.

This is the voltage-ampere requirement of a device designed to convert electric energy to a non-electrical form.

A device for converting one form of energy or fuel into useful energy or work.

The ratings under which specified appliances convert energy sources into useful energy, as determined by procedures established by the U.S. Department of Energy.

Energy terms

Any number of solar photovoltaic modules or solar thermal collectors or reflectors connected together to provide electrical or thermal energy.

The non-combustible residue of a combusted substance composed primarily of alkali and metal oxides.

Abbreviation for the American Society of Heating, Refrigeration, and Air-Conditioning Engineers.

A type of electric generator that produces alternating current that matches an existing power source.

The pressure of the air at sea level; one standard atmosphere at zero degrees centigrade is equal to 14.695 pounds per square inch (1.033 kilograms per square centimeter).

An interior court to which rooms open.

The usually unfinished space above a ceiling and below a roof.

A fan mounted on an attic wall used to exhaust warm attic air to the outside.

A passive or mechanical device used to ventilate an attic space, primarily to reduce heat buildup and moisture condensation.

The process of determining energy consumption, by various techniques, of a building or facility.