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)

substrate
The physical material upon which a photovoltaic cell is applied.
subsystem
Any one of several components in a photovoltaic system; such as, array, controller, batteries, inverter, and load.
sulfation
A condition that afflicts unused and discharged batteries; large crystals of lead sulfate grow on the plate, instead of the usual tiny crystals, making the battery extremely difficult to recharge.
superconducting magnetic energy storage; SMES
Superconducting magnetic energy storage technology uses the superconducting characteristics of low-temperature materials to produce intense magnetic fields to store energy.

It has been proposed as a storage option to support large-scale use of photovoltaics as a means to smooth out fluctuations in power generation.

superconductivity
The abrupt and large increase in electrical conductivity exhibited by some metals as the temperature approaches absolute zero.
superstrate
The covering on the sunny side of a photovoltaic module, providing protection for the photovoltaic materials from impact and environmental degradation while allowing maximum transmission of the appropriate wavelengths of the solar spectrum.
surge capacity
The maximum power, usually three to five times the rated power, that can be provided over a short time.
system availability
The percentage of time (usually expressed in hours per year) when a photovoltaic system will be able to fully meet the load demand.
system operating voltage
The photovoltaic array output voltage under load.

The system operating voltage is dependent on the load or batteries connected to the output terminals.

tare loss
Loss caused by a charge controller. One minus tare loss, expressed as a percentage, is equal to the controller efficiency.
temperature compensation
A circuit that adjusts the charge controller activation points depending on battery temperature.

This feature is recommended if the battery temperature is expected to vary more than ±5°C from ambient temperature.

temperature factors
It is common for three elements in photovoltaic system sizing to have distinct temperature corrections: a factor used to decrease battery capacity at cold temperatures; a factor used to decrease photovoltaic module voltage at high temperatures; and a factor used to decrease the current carrying capability of wire at high temperatures.
thermophotovoltaic cell; TPV
A device where sunlight concentrated onto a absorber heats it to a high temperature, and the thermal radiation emitted by the absorber is used as the energy source for a photovoltaic cell that is designed to maximize conversion efficiency at the wavelength of the thermal radiation.
thick-crystalline materials
Semiconductor material, typically measuring from 200-400 microns thick, which is cut from ingots or ribbons.
thin film
A layer of semiconductor material; such as, copper indium diselenide or gallium arsenide, a few microns or less in thickness, used to make photovoltaic cells.
—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.