A group of solar photovoltaic modules connected together.

A method of depositing thin semiconductor photovoltaic) films. With this method, physical processes, such as thermal evaporation or bombardment of ions, are used to deposit elemental semiconductor material on a substrate.

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

A particle of light that acts as an individual unit of energy.

A power plant that uses two thermodynamic cycles to achieve higher overall system efficiency; e.g.: the heat from a gas-fired combustion turbine is used to generate steam for heating or to operate a steam turbine to generate additional electricity.

A device that that converts direct current electricity (from for example a solar photovoltaic module or array) to alternating current for use directly to operate appliances or to supply power to a electricity grid.

A battery that uses lithium in the negative electrode and a metal sulfide in the positive electrode, and the electrolyte is molten salt; can store large amounts of energy per unit weight.

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

A system of astronomical time in which the sun crosses the true north-south meridian at 12 noon, and which differs from local time according to longitude, time zone, and equation of time.

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

A frequently used room or area that is maintained at a more comfortable level than the rest of the house; also known as a "warm room."

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

Standardized codes used to classify businesses by type of activity they engage in.

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.

The amount of conditioned air to be supplied by a cooling system; usually the maximum amount to be delivered based on a specified number of cooling degree days or design temperature.

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

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.

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