Renewable Energy Systems - Photovoltaic Solar Power Systems

Vocabulary flashcards for key concepts related to photovoltaic (PV) solar power systems, covering PV cells, system components, shading effects, and sizing calculations.

Photovoltaics (PV)

Direct conversion of light into electricity at the atomic level.

PV Effect

The effect that causes semi-conducting materials to absorb photons of light and release electrons.

P-N Junction

An electrical field created near the top surface of a PV cell where N-type and P-type materials meet.

I-V Curve

A graph showing the relationship between current and voltage of a PV module/array, providing performance information.

Open Circuit Voltage (Voc)

Voltage at open circuit i.e. when no current is flowing .

Short Circuit Current (Isc)

Current at short circuit i.e. when voltage is zero.

Monocrystalline Solar Panels

Solar panels with cells made from a single silicon crystal.

Polycrystalline Solar Panels

Solar panels with cells made from multiple silicon fragments melted together.

Cells’ Packing Density (PD)

Actual area occupied by the solar cells divided by the total area of the solar panel.

Multi-junction Cells

Two or more solar cells stacked to exploit different portions of the solar spectrum.

Balance of System (BOS)

Components other than the PV modules in a PV system, including wiring, switches, and protection devices.

Azimuth Angle

The angle between the sun's position and a reference direction.

Altitude Angle

The angle of the sun relative to the Earth's horizon.

Maximum Power Point (MPP)

The point on a power curve with the highest power output.

Maximum Power Point Tracker (MPPT)

A device that continually finds the MPP of a solar PV panel or array.

Charge Controller

Voltage and/or current regulator to keep batteries from overcharging

Bypass Diode

Wired within the PV module to provide an alternate current route when a cell or panel becomes shaded or faulty.

Blocking Diode

Used to prevent current from flowing from a battery back to the array.

Stand Alone (Off-grid) System

A PV system where the panel(s), Battery(ies) and charge controller are not connected to the power grid.

Grid Tie System

A PV system connected to the power grid.

Depth of Discharge (DoD)

The amount a battery is discharged; expressed as a percentage.

VRLA batteries

Batteries where a valve regulates the pressure. An example is lead acid batteries.