• A solar panel — also called a photovoltaic (PV) module — is made of many solar cells (usually crystalline-silicon or thin-film)
Specifications
Pmax (or Wp / Watt-peak)
The maximum DC power the panel can produce under Standard Test Conditions (STC: 1000 W/m² solar irradiance, 25 °C cell temp, standard spectrum) — basically the panel’s “rated output.”
Panel Efficiency (%)
How effectively the panel converts sunlight into electricity. Higher efficiency → more power for less surface area (useful when roof/space is limited). Typical modern solar panels: ~ 15% to ~ 23%.
Vmp (Voltage at Max Power)
The DC voltage output when the panel is producing its max power (Pmax). Important for matching with inverters or charge controllers — ensures the system works efficiently.
Imp (Current at Max Power)
The DC current (amps) at the max power point. Used together with Vmp to determine actual output (Power = V × I).
Voc (Open-Circuit Voltage)
The voltage across the panel when no load is connected — maximum possible voltage. Useful for safety, designing string voltages (series connection) and ensuring inverter/ charge controller specs aren’t exceeded.
Isc (Short-Circuit Current)
The current when the panel’s output is shorted (terminals connected), basically the maximum possible current. Helps size cables, fuses, and protection devices.
Temperature Coefficient
How much the panel’s power (and/or voltage/current) drops when the temperature rises above standard test conditions. Important in hot climates (like Nigeria) because performance degrades with heat.
Operating Temperature Range and Durability
Specifies the environmental range (e.g. –40 °C to +85 °C), resistance to weather, moisture, UV, etc. Ensures panel lasts long and withstands local climate conditions.
