Knowledge Center
How solar power works
Line diagram
The six components
A grid-connected solar power system typically involves six basic components: solar panels, a DC-to-AC inverter, a solar generation meter, the main electrical (AC) distribution panel, a net meter, and the utility grid connection.
- 01
Solar panels convert solar energy into electricity in DC form.
- 02
DC current generated by the panels is converted into AC current by the DC-to-AC solar inverter.
- 03
Generated power is measured by a solar meter before going to the electrical panel.
- 04
AC current generated by solar power is then merged with the grid load at the main electrical panel.
- 05
Any excess solar generation not used by the load goes to the grid (export)…
- 06
…and supply is drawn from the grid (import) when solar power is not available.
- 07
The utility grid (Torrent Power or DGVCL) supplies electricity and takes back the excess solar generation.
System types
Three ways to generate
Off-Grid / Standalone Solar Power System
A stand-alone (off-grid) solar power system is an off-the-grid electricity system for locations not fitted with an electricity distribution network. Typical systems include one or more methods of electricity generation, energy storage and regulation, and are independent of the utility grid. Storage is typically a battery bank; power drawn directly from the battery is extra-low-voltage DC, used especially for lighting and DC appliances. An inverter generates low-voltage AC for more typical appliances.
Grid-Connected Solar Power System
A grid-connected solar power plant generates electricity and is connected to the utility grid. It consists of solar panels and one or several inverters, ranging from small residential and commercial rooftop systems to large utility-scale stations. Unlike stand-alone systems, it rarely includes an integrated battery, as they are still very expensive. When conditions are right, the system supplies excess power - beyond the connected load - to the utility grid.
Hybrid Solar Power System
A hybrid system combines the two above. It uses solar power when the sun is available, charges the battery, and - in the absence of grid power - uses the battery as the source of power. The cost of such a system is higher and it affects the overall payback period of the project.
Current flow
What happens in different conditions
Daytime - condition 1
Generation is less than the load
The additional power requirement is supplied by the grid. Some power is imported. No export.
Daytime - condition 2
Generation is more than the load
Excess solar generation is fed back to the grid. Power is exported. No import.
Night or evening
Solar power is not available
All power is imported from the utility grid - like a normal premises without a solar plant. No export, all import.
Net metering
Your roof pays you back
Net metering measures the difference between the solar energy your system exports to the grid and the energy you import from it. Your DISCOM bills you on the net - so the units your roof sends back reduce what you pay.
Our YouTube channel walks through the systems and components in detail.
