Short answer
Choose on-grid if your goal is reducing your electricity bill and your grid supply is reliable. It costs less per kW and has no battery to replace. Choose hybrid if you need power during outages. The deciding question is not which is technically better, but whether you need backup: a hybrid system costs meaningfully more and that cost only pays off if outages actually affect you.
How an on-grid system works
An on-grid system connects your solar array to your existing grid connection through an inverter. During daylight, solar powers your loads directly. If you generate more than you are consuming, the surplus can be exported to the grid where net metering is available.
There is no battery. During a grid outage the inverter disconnects automatically and the system stops producing. This is a safety requirement, not a fault. It prevents your system from energising lines that utility staff may be working on.
How a hybrid system works
A hybrid system uses an inverter capable of managing three sources at once: solar, battery and grid. Solar powers your loads and charges the battery during the day. When the grid fails, the inverter isolates from the grid and continues supplying your backed-up circuits from the battery.
The key design decision is which circuits get backed up. Backing up the entire property requires a much larger battery than backing up lights, fans, a fridge and a few sockets. Most customers are better served by a carefully chosen subset.
What the difference costs you
A hybrid system costs more for two reasons: the hybrid inverter itself, and the battery. The battery is usually the larger share, and unlike the modules, it has a finite cycle life and will need replacement at some point during the system life.
This is the honest trade-off. A battery does not generate additional electricity. It stores what has already been generated, with a small round-trip loss. If your supply is reliable, that money buys you nothing you would notice. If outages are frequent, it buys you something you would notice immediately.
How to decide
Ask yourself how many hours of outage you experienced in the last year and how much they actually disrupted you. If the honest answer is "not much", an on-grid system is the better use of the same budget. You could install more capacity instead and offset more of your bill.
If outages are regular, or if you have equipment that cannot tolerate interruption, hybrid is worth it. A middle path also exists: specify a hybrid-ready inverter now and add the battery later. This costs slightly more upfront than a plain on-grid inverter but preserves the option without paying for the battery today.
- Reliable supply, goal is bill reduction → on-grid
- Frequent or long outages → hybrid with battery
- Unsure, but want to keep options open → hybrid-ready inverter, battery added later
Related questions
Can I add a battery to an on-grid system later?
Only if the inverter supports it. A standard on-grid string inverter cannot simply have a battery attached. You would need to replace the inverter or add separate equipment. If there is any chance you will want backup later, specify a hybrid-ready inverter at the design stage. Tell your installer this before the design is finalised, not after installation.
Why does my solar system stop working during a power cut?
If you have an on-grid system, this is expected behaviour and not a fault. Grid-tied inverters are required to disconnect when grid supply fails, so that your system cannot energise the distribution lines while utility staff may be working on them. Only a hybrid or off-grid system with a battery can continue supplying your loads during an outage.
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