| Word | Description |
| I-V curve | A graphical presentation of the current versus the voltage from a photovoltaic cell as the load is increased from the short circuit (no load) condition to the open circuit (maximum voltage) condition. The shape of the curve characterizes cell performance. |
| Incandescent Lights | Regular light bulbs that use a glowing filament to product light by emitting photons. |
| Installed power | Power delivered by a photovoltaic module or a photovoltaic array, under standard test conditions (irradiance of 1 000 W/m2, cell junction temperature of 250C, AM1,5 solar spectrum). Also said STC output power. Unit: W. |
| Inverter | Device that converts direct current (d.c.) into alternating current (a.c.). |
