On-grid, hybrid and off-grid solar systems explained

On-grid, hybrid and off-grid describe how a solar power system relates to the electricity network, battery storage and the loads it must support. They are useful starting points, but the detailed design still depends on the actual equipment and property.

On-grid solar PV

An on-grid system operates alongside the public electricity supply. Solar energy serves loads at the property first, and any shortfall is imported from the grid. Surplus generation may be exported, subject to the system and connection arrangement.

A standard grid-tied inverter normally stops supplying power when the network is unavailable. This anti-islanding behaviour protects people working on the network. If backup is required, it must be designed into the system rather than assumed from the presence of solar panels.

Typical fit: Homes and businesses focused on solar generation and self-consumption without an immediate need for battery backup.

Hybrid solar and battery

A hybrid system combines solar generation and battery storage through equipment designed to coordinate both. It can store surplus daytime energy for use later and may provide backup when the correct inverter outputs, switching, protection and distribution circuits are included.

Hybrid does not automatically mean whole-property backup. Check which circuits will remain live, the maximum backup power, changeover behaviour, battery capacity and whether solar can continue charging the battery during an outage.

Typical fit: Homes and businesses seeking higher solar self-consumption, time-of-use optimisation or planned backup for selected loads.

Off-grid power

An off-grid system operates without relying on the public electricity supply. Generation, battery storage and the inverter must support the expected loads through changing daily and seasonal conditions. A generator or other secondary source may be included for resilience.

Off-grid design starts with the load profile and the worst credible generation period, not the best summer day. Efficient appliances, load control and realistic expectations can reduce equipment size and improve reliability.

Typical fit: Remote properties, cabins, agricultural sites, mobile and marine systems, or applications where a reliable network connection is unavailable.

Quick comparison

System	Grid relationship	Battery	Main design focus
On-grid	Operates with public supply	Optional via a separate approach	PV yield, self-use, inverter and connection
Hybrid	Operates with public supply	Integrated into the system	Compatibility, energy shifting and backup circuits
Off-grid	No network reliance	Normally essential	Loads, autonomy, winter generation and resilience

Questions that decide the category

• Is a reliable public electricity supply available?
• Is the priority lower grid use, backup power, complete independence or a combination?
• Which loads must run during an outage, and for how long?
• Is solar already installed, and can it be integrated or should storage be added separately?
• What equipment space, cable routes and mounting area are available?
• Who will design, install, test and commission the system?

Common misconception: A large battery does not guarantee strong backup performance. The inverter output, battery discharge limit, changeover arrangement and circuits connected to backup all matter.

Compare systems and inverters or ask about a pre-built cabinet.