Solar system types: hybrid, off grid and grid tied with storage

There are three common ways to arrange a solar photovoltaic system for a home or business. The diagrams below show single phase layouts for simplicity, but the same thinking applies to three phase, whether with one three phase inverter or several in parallel.

Hybrid: inverter or charger with storage, self consumption and optional export

Energy flows in both directions. Export back to the grid is adjustable and can be set as low as zero watts, which matters where the network operator restricts it. Grid power and the inverter supply the loads in parallel, batteries expand in modules, and there are extra ports for adding more solar panels later.

Off grid with grid back up and storage, self consumption without export

Here energy flows one way only, from the grid to the loads. If demand exceeds the inverter's peak power the grid carries the whole load rather than the system failing. Batteries expand in modules as before, and again there is room to add panels.

Grid tied with a feed in tariff and AC charged storage

A grid tied inverter with a feed in tariff, where the storage is charged from AC rather than directly from the array.

Four ways to configure a 5.5kW storage inverter

The Voltasol ESS 5.5 is an all in one unit, and how much of the house it covers is a configuration choice rather than a hardware one:

• Basic. Add the storage to the existing household supply and leave everything else as it is.
• Critical loads only. Supply specific areas and critical circuits off grid, independently of the mains.
• Whole house off grid. Supply the entire property off grid, keeping the AC input as back up.
• Parallel units. For larger properties, run several units in parallel to cover the whole house.