A heating system, such as a solar water heater or geothermal heatpump, in which the working fluid is heated and used directly; in an open-loop solar system, the domestic water is circulated in the collector loop.

A wood or gas burning heating appliance that fits into the opening or protrudes on to the hearth of a conventional fireplace.

The effect of cooling by the radiation of heat from a building to the night sky.

A class of power generator that is not a regulated utility and that has generating plants for the purpose of supplying electric power required in the conduct of their industrial and commercial operations.

The discomfort or interference with visual perception when viewing a bright object against a dark background.

The arrangement, proportion, and design of windows in a building.

A diagram that indicates the average percentage of time that the wind blows from different directions, on a monthly or annual basis.

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

A unit of measurement for the ability of a material to retard the diffusion of water vapor at 73.4 F (23 C). A perm, short for permeance, is the number of grains of water vapor that pass through a square foot of material per hour at a differential vapor p ...

A thermal storage wall is a south-facing wall that is glazed on the outside. Solar heat strikes the glazing and is absorbed into the wall, which conducts the heat into the room over time. The walls are at least 8 in thick. Generally, the thicker the wall, ...

A device for converting mechanical energy to electrical energy.

A type of heating system where heat, resulting when electric current flows through an "element" or conductor, such as Nichrome, which has a high resistance, is radiated to a room.

The practice of using a single meter to measure consumption and generation of electricity by a small generation facility (such as a house with a wind or solar photovoltaic system). The net energy produced or consumed is purchased from or sold to the gener ...

A device that tracks the movement of the sun; used to orient solar concentrating systems.

A device that removes contaminants, by mechanical filtration, from the fresh air stream before the air enters the living space. Filters can be installed as part of a heating/cooling system through which air flows for the purpose of removing particulates b ...

A device for converting continuous circular motion into reciprocating rectilinear motion.

A construction element used for ceiling support.

A unit used to rate the performance of a solar photovoltaic (PV) cells, modules, or arrays; the maximum nominal output of a PV device, in Watts (Wp) under standardized test conditions, usually 1000 Watts per square meter of sunlight with other conditions, ...

The processes that a work input/output system undergoes and in which the initial and final states are identical.

The wind speed and direction in an undisturbed flow.