Solar comes with its own vocabulary. Keep this glossary handy when reading quotations or talking to installers.
Basic terms
- Photovoltaic (PV): Technology that converts sunlight directly into electricity.
- Solar panel / module: A unit made of many solar cells, producing DC electricity.
- Solar cell: The basic unit that converts light into electricity, usually made of silicon.
- Watt-peak (Wp): Rated power of a panel under standard test conditions.
- kWp: Total rated capacity of a solar system (1 kWp = 1,000 Wp).
- kWh / Unit: A measure of energy. Your bill counts units.
System types
- On-grid: Connected to the grid, usually without batteries.
- Off-grid: Not connected to the grid; uses batteries.
- Hybrid: Connected to the grid and has batteries.
Equipment
- Inverter: Converts DC from panels into AC for your home.
- Hybrid inverter: Inverter that works with both the grid and batteries.
- Microinverter: A small inverter attached to each panel.
- Charge controller: Manages battery charging in off-grid systems.
- MPPT: Maximum Power Point Tracking — gets the most power from panels.
- ACDB / DCDB: Distribution boxes with protection devices on the AC and DC sides.
- SPD: Surge Protection Device that protects against voltage spikes.
- Lightning arrester: Device that safely directs lightning to the ground.
- MC4 connector: Standard connector used to join solar cables.
Panel technology
- Monocrystalline: High-efficiency panels made from single-crystal silicon.
- Mono PERC: A monocrystalline technology with a rear reflective layer.
- TOPCon: Newer high-efficiency cell technology.
- Bifacial: Panels that capture light on both sides.
- Half-cut cells: Cells cut in half to reduce losses and improve shade tolerance.
- Temperature coefficient: How much output drops as panel temperature rises.
- Degradation: Gradual loss of panel output over time.
Policy and approval terms
- Net metering: Billing based on the difference between imported and exported units.
- Net meter / bi-directional meter: Meter that records both import and export.
- ALMM: Approved List of Models and Manufacturers maintained by MNRE.
- DCR: Domestic Content Requirement — panels using Indian-made cells.
- ESCOM: Electricity Supply Company (e.g., GESCOM, BESCOM in Karnataka).
- Sanctioned load: Maximum load approved for your electricity connection.
- Feasibility approval: ESCOM approval confirming solar can be connected.
- Commissioning: Final step after inspection when the system officially starts operating.
The bottom line
Understanding these terms helps you ask better questions and compare offers confidently.
Have a term you don't understand in your quotation? Ask us — we'll explain it in plain language.
