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)

operating point
The current and voltage that a photovoltaic module or array produces when connected to a load.

The operating point is dependent on the load or the batteries connected to the output terminals of the array.

orientation
Placement with respect to the cardinal directions, north, south, east, west; azimuth is the measure of orientation from the north.
overcharge
Forcing current into a fully charged battery.

The battery will be damaged if overcharged for a long period.

packing factor
The ratio of array area to actual land area or building envelope area for a system; or, the ratio of total solar cell area to the total module area, for a module.
parallel connection
A way of joining solar cells or photovoltaic modules by connecting positive leads together and negative leads together; such a configuration increases the current, but not the voltage.
passivation
A chemical reaction that eliminates the detrimental effect of electrically reactive atoms on a solar cell's surface.
peak demand/load
The maximum energy demand or load in a specified time period.
peak power current
Amperes produced by a photovoltaic module or array operating at the voltage of the I-V curve that will produce maximum power from the module.
peak power point
Operating point of the I-V (current-voltage) curve for a solar cell or photovoltaic module where the product of the current value times the voltage value is a maximum.
peak sun hours
The equivalent number of hours per day when solar irradiance averages 1,000 w/m2; for example, six peak sun hours means that the energy received during total daylight hours equals the energy that would have been received had the irradiance for six hours been 1,000 w/m2.
peak watt
A unit used to rate the performance of solar cells, modules, or arrays; the maximum nominal output of a photovoltaic device, in watts (Wp) under standardized test conditions, usually 1,000 watts per square meter of sunlight with other conditions; such as, temperature specified.
phosphorous; P
A chemical element used as a dopant in making n-type semiconductor layers.
photocurrent
An electric current induced by radiant energy.
photoelectric cell
A device for measuring light intensity that works by converting light falling on, or reach it, to electricity, and then measuring the current; used in photometers.
photoelectrochemical cell
A type of photovoltaic device in which the electricity induced in the cell is used immediately within the cell to produce a chemical, such as hydrogen, which can then be withdrawn for use.
—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.