Air that provides the necessary oxygen for complete, clean combustion and maximum heating value.

A solar collector in which the absorber is contained in a sealed glass tube, thereby providing for relatively high temperature heat gain.

A type of inverter that produces square wave output.; consists of a DC source, four switches, and the load. The switches are power semiconductors that can carry a large current and withstand a high voltage rating. The switches are turned on and off at a c ...

Power plants, whose output depends on a factor(s) that cannot be controlled by the power generator because they utilize intermittent resources such as solar energy or the wind.

A toilet that uses less water than a standard one during flushing, for the purpose of conserving water resources.

A concrete pad that sits on gravel or crushed rock, well-compacted soil either level with the ground or above the ground.

The temperature of the air as measured by a standard thermometer.

In reference to solar photovoltaic devices, the growth of one crystal on the surface of another crystal. The growth of the deposited crystal is oriented by the lattice structure of the original crystal.

A load management objective that moves loads from on-peak periods to off-peak periods.

A nationally recognized energy rating program that gives builders, mortgage lenders, secondary lending markets, homeowners, sellers, and buyers a precise evaluation of energy losing deficiency's in homes. Builders can use this system to gauge the energy q ...

A type of lamp that produces light from sodium gas contained in a bulb operating at a partial pressure of 0.13 to 1.3 Pascal. The yellow light and large size make them applicable to lighting streets and parking lots.

A law that requires electric utilities to purchase electricity produced from qualifying power producers that use renewable energy resources or are cogenerators. Utilities are required to purchase power at a rate equal to the avoided cost of generating the ...

An automatic valve that is opened or closed by an electromagnet.

The sum of the ratings of the electricity consuming apparatus connected to a generating system.

Waste water from a household source other than a toilet. This water can be used for landscape irrigation depending upon the source of the greywater.

The vacancy where an electron would normally exist in a solid; behaves like a positively charged particle.

Amorphous silicon with a small amount of incorporated hydrogen. The hydrogen neutralizes dangling bonds in the amorphous silicon, allowing charge carriers to flow more freely.

A method of controlling a wind turbine's speed by varying the orientation, or pitch, of the blades, and thereby altering its aerodynamics and efficiency.

A building element that provides protection against the sun, wind, and precipitation.

A curve that displays load values on the horizontal axis in descending order of magnitude against the percent of time (on the vertical axis) that the load values are exceeded.