Three system types, one decision, and the wrong choice costs you either money you did not need to spend or power you cannot use.
The difference in one table
| On grid | Off grid | Hybrid | |
| Battery | None | Required | Required |
| Runs during a power cut | No | Yes | Yes |
| Exports surplus to the grid | Yes | No | Yes |
| Needs net metering | Yes | No | Preferably |
| Relative cost | Lowest | High | Highest |
On grid, and why most people should choose it
An on grid system has no battery. Surplus generation goes to the grid through a net meter and comes back as credit against your bill. It is the cheapest per unit generated and has the fewest components that can fail.
One limitation surprises people. During a power cut an on grid system shuts down, even in bright sunshine. This is deliberate and required by the grid code. It stops your system feeding electricity into lines that linemen may be working on.
Off grid, and who it is actually for
An off grid system has no grid connection at all. Everything generated is used immediately or stored. It suits locations without a reliable connection: remote farms, telecom towers, border installations.
For a city rooftop with a working connection, going off grid means paying for storage to replace a grid that already works, and giving up the ability to export. It is rarely the right answer where a connection exists.
Hybrid, and the honest case for it
A hybrid system does both, and costs the most. The question is not whether backup would be nice to have. It is whether the battery costs you less than the outages do.
For a home with occasional short cuts, usually not. For a business losing production, or a site already running a diesel generator, usually yes, and in that case the comparison should be made against the generator rather than against an on grid system.
What this means for the panels
Very little, which is worth saying plainly. The same modules work in all three configurations. What changes is the inverter and whether a battery is fitted. If anyone tells you a particular panel is required for a hybrid system, ask them why.
Frequently asked questions
Which type is best for a home in India?
On grid in most cases, provided your DISCOM offers net metering and supply is reasonably reliable. Hybrid if power cuts are frequent or long enough to matter.
Does an on grid system work during a power cut?
No. It disconnects automatically for the safety of anyone working on the lines. A battery and a hybrid inverter are what provide backup.
Can I convert an on grid system to hybrid later?
Only if the inverter supports a battery input. Many string inverters do not, which means replacing the inverter as well, so converting later usually costs more than specifying hybrid at the start.
