Photovoltaic Conversion Efficiency Terms +

(solar electricity technical terms applying to electricity, power generation, concentrating solar power, or CSP, solar heating, solar lighting, and solar electricity)

concentrator
A photovoltaic module, which includes optical components; such as, lenses (Fresnel lens) to direct and concentrate sunlight onto a solar cell of smaller area.

Most concentrator arrays must directly face or track the sun. They can increase the power flux of sunlight hundreds of times.

conduction band or conduction level
An energy band in a semiconductor in which electrons can move freely in a solid, producing a net transport of charge.
conductor
The material through which electricity is transmitted; such as, an electrical wire, or transmission or distribution line.
contact resistance
The resistance between metallic contacts and the semiconductor.
converter
A unit that converts a direct current (dc) voltage to another direct current voltage.
copper indium diselenide; CuInSe2 or CIS
A polycrystalline thin-film photovoltaic material (sometimes incorporating gallium (CIGS) and/or sulfur).
crystalline silicon
A type of photovoltaic cell made from a slice of single-crystal silicon or polycrystalline silicon.
current at maximum power; Imp
The current at which maximum power is available from a module.
cutoff voltage
The voltage levels (activation) at which the charge controller disconnects the photovoltaic array from the battery or the load from the battery.
cycle
The discharge and subsequent charge of a battery.
Czochralski process, Czochralski method, Czochralski crystal growth
A method of growing large size, high quality semiconductor crystal by slowly lifting a seed crystal from a molten bath of the material under careful cooling conditions.

The most widely used technique for making single-crystal silicon, in which a seed of single-crystal silicon contacts the top of molten silicon.

As the seed is slowly raised, atoms of the molten silicon solidify in the pattern of the seed and extend the single-crystal structure.

dangling bonds
A chemical bond associated with an atom on the surface layer of a crystal.

The bond does not join with another atom of the crystal, but extends in the direction of exterior of the surface.

days of storage
The number of consecutive days the stand-alone system will meet a defined load without solar energy input.

This term is related to system availability.

DC-to-DC converter
Electronic circuit to convert direct current voltages (photovoltaic module voltage) into other levels (load voltage).

it can be part of a maximum power point tracker.

deep discharge
Discharging a battery to 20 percent or less of its full charge capacity.
—The information for the entries in this unit were compiled primarily from data
provided in the following source:

"U.S. Department of Energy, Energy Efficiency and Renewable Energy"
consisting of definitions of many important terms having to do with electricity,
power generation, concentrating solar power (CSP), solar heating, solar lighting,
and solar electricity, also known as photovoltaic (PV).

Information was also compiled from the

Academic Press Dictionary of Science and Technology; Edited by Christopher Morris;
Academic Press; Harcourt Brace Jovanovich, Publishers; New York; 1992;
as well as,
McGraw-Hill Dictionary of Scientific and Technical Terms, 4th edition;
Sybil P. Parker, editor in chief; McGraw-Hill, Inc.; 1989.

Index of additional Scientific and Technological Topics.