Self-consumption solar inverters

A self-consumption inverter converts the direct current from the panels into alternating current to power the appliances in your home or business. It is the piece of equipment that determines how the entire system operates: how much power it can supply, how it manages surplus energy, and whether you will be able to add batteries at a later date.

A self-consumption inverter or a hybrid inverter?

The self-consumption system converts and feeds in: it uses the electricity generated to meet consumption needs and feeds any surplus into the grid. The hybrid It also includes the battery charging stage.

The practical decision is not a technical one but a matter of timing: if you’re never going to install batteries, the self-consumption system is cheaper and sufficient. If there’s a possibility of installing them in a few years’ time, the hybrid system avoids having to replace the entire inverter, and the difference in the initial price is less than the cost of replacing it later.

What inverter power do I need?

It is sized according to two criteria at the same time. The DC/AC ratio between the panels and the inverter, which in Spain is usually between 1.1 and 1.3: with 6 kW of panels, a 5 kW inverter performs better for more hours of the year. And the contracted power, because the inverter must not exceed the capacity of your connection.

Oversizing the inverter “just in case” does not increase output: it results in the equipment operating at partial load, where conversion efficiency is lower.

What types of self-consumption investors do we have?

We are working on the range Fronius GEN24 in the Primo (single-phase) and Symo (three-phase) versions, ranging from 3 to 10 kW. These are the same units as those in the Plus range but without the battery stage, whilst the electronics and control software are identical.

If you want to restrict network injection, you will also need a energy meter. And to validate the string configuration, use the Series and parallel panel calculator.