The structural elements (walls, roof, floor, foundation) of a building that encloses conditioned space; the building shell.

The amount of heat produced from the complete combustion of a unit of fuel. The higher (or gross) heating value is that when all products of combustion are cooled to the pre-combustion temperature, water vapor formed during combustion is condensed, and ne ...

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

The quantity of heat produced to change a unit weight of a liquid to vapor with no change in temperature.

A device that releases pressure within a radiator when the pressure inside exceeds the operating limits of the vent.

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

A type of window glass that contains special tints that cause the window to absorb as much as 45% of incoming solar energy, to reduce heat gain in an interior space. Part of the absorbed heat will continue to be passed through the window by conduction and ...

A building design that uses structural elements of a building to heat and cool a building, without the use of mechanical equipment, which requires careful consideration of the local climate and solar energy resource, building orientation, and landscape fe ...

The wheeling of electric power in amounts and at prices that generally have been negotiated in longterm contracts between the generator and a distributor or very large consumer of power.

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 space heating device that burns pellets; are more efficient, clean burning, and easier to operate relative to conventional cord wood burning appliances.

The total diffuse and direct insolation on a horizontal surface, averaged over a specified period of time.

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.

An electrical inverter that inverts direct current electricity to alternating current electricity, and that uses another alternating current source, such as an electric power transmission and distribution network (grid), for voltage and frequency referenc ...

The change in heat content that occurs with a change in phase and without change in temperature.

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

The alignment of a building along a given axis to face a specific geographical direction. The alignment of a solar collector, in number of degrees east or west of true south.

The ratio of the radiant energy (heat) leaving (being emitted by) a surface to that of a black body at the same temperature and with the same area; expressed as a number between 0 and 1.

A hydropower plant that is operated at maximum allowable capacity for part of the day and is either shut down for the remainder of the time or operated at minimal capacity level.

The rate of flow of the wind undisturbed by obstacles.