Solar DC Optimisers

Solar DC optimisers (or optimizers in American English) are, as the name suggests, designed to improve the performance of home solar systems and commercial PV systems.

In general, Solar DC Optimisers offer the following functions:

  1. Improved performance of solar panel groups in partially shaded conditions;
  2. Monitoring of each panel, and groups of panels in more detail than in traditional ‘string inverter’ based systems;
  3. More panels per string, reducing some other equipment costs such as isolators; and
  4. Remote isolation of the panels at the panel (in the event of an emergency, without needing to climb onto the roof .

Some systems offer other functions. For example, some optimisers also detect faults in the general DC wiring, such as DC arcs.

The most popular brands of Solar DC Optimisers are Tigo and SolarEdge

How do optimisers differ from micro-inverters ?

Micro-inverters convert DC energy from the panels into AC electricity on the roof.  This makes micro-inverter systems inherently safer than traditional string inverter based systems.  However, to convert the DC energy to AC electricity, more parts are required on the roof, which could mean more points of failure. The idea of DC optimisers is to enable each panel to perform on its own, and be monitored individually, whilst keeping the parts count low, and minimising heat sensitive items being exposed to the hot rooftop environment.