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)
maintenance-free battery, maintenance free battery
A sealed battery to which water cannot be added to maintain electrolyte level.
majority carrier
Current carriers (either free electrons or holes) that are in excess in a specific layer of a semiconductor material (electrons in the n-layer, holes in the p-layer) of a cell.
maximum power point tracker; MPPT
Means of a power conditioning unit that automatically operates the photovoltaic generator at its maximum power point under all conditions.
maximum power point; MPP
The point on the current-voltage (I-V) curve of a module under illumination, where the product of current and voltage is maximum.
For a typical silicon cell, this is at about 0.45 volts.
maximum power tracking
Operating a photovoltaic array at the peak power point of the array's I-V curve where maximum power is obtained. Also called "peak power tracking".
megawatt; MW
A 1,000 kilowatts, or one million watts; standard measure of electric power plant generating capacity.
megawatt-hour, megawatt hour
One thousand kilowatt-hours or one million watt-hours.
microgroove
A small groove scribed into the surface of a solar cell, which is filled with metal for contacts.
minority carrier
A current carrier, either an electron or a hole, that is in the minority in a specific layer of a semiconductor material; the diffusion of minority carriers under the action of the cell junction voltage is the current in a photovoltaic device.
minority carrier lifetime
The average time a minority carrier exists before recombination.
modified sine wave
A waveform that has at least three states (for example, positive, off, and negative).
It has less harmonic content than a square wave.
modified sine wave
A waveform that has at least three states (such as, positive, off, and negative).
It has less harmonic content than a square wave.
modularity
The use of multiple inverters connected in parallel to service different loads.
module derate factor
A factor that lowers the photovoltaic module current to account for field operating conditions such as dirt accumulation on the module.
monolithic
Fabricated as a single structure.
Index of additional Scientific and Technological Topics.