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 ...

A measure of the flow of current (in amperes) over one hour.

The annual solar savings of a solar building is the energy savings attributable to a solar feature relative to the energy requirements of a non-solar building.

A wall that carries ceiling rafters or roof trusses.

The process of removing a power plant, apparatus, equipment, building, or facility from operation.

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

A component of a heating or ventilation appliance used to conduct fresh air into, or waste air or combustion gases out of, an appliance or interior space.

A category of electric power producer established under the Public Utility Regulatory Policy Act (PURPA) of 1978, that includes small-power producers (SPP) who use renewable sources of energy such as biomass, geothermal, hydroelectricity, solar (thermal a ...

A mechanical device used for air circulation and to provide cooling.

A movable plate used to control air flow; in a wood stove or fireplace, used to control the amount and direction of air going to the fire.

A unit for measuring the extent that the outdoor daily average temperature (the mean of the maximum and minimum daily dry-bulb temperatures) falls below (in the case of heating, see Heating Degree Day), or falls above (in the case of cooling, see Cooling ...

That fraction of annual energy demand supplied by a solar system.

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

Biomass converted directly to energy or converted to liquid or gaseous fuels such as ethanol, methanol, methane, and hydrogen.

The amount of heat required to raise the temperature of one pound of water one degree Fahrenheit; equal to 252 calories.

A type of hydroturbine in which the entire generator is mounted inside the water passageway as an integral unit with the turbine. These installations can offer significant reductions in the size of the powerhouse.

The control of the quality, quantity, and temperature-humidity of the air in an interior space.

A building architectural element (vestibule) with two airtight doors that reduces the amount of air infiltration and exfiltration when the exterior most door is opened.

The space-conditioning load of a building.

A graph that indicates the distribution of wind speeds as a function of the cumulative number of hours that the wind speed exceeds a given wind speed in a year.