How is calculated the efficiency at STC?

[Edd V. Asce]

Hello!

Please, could you explain how is calculated efficiency at STC that appear in the loss diagram at the end of each simulation.

Thanks in advance.

Regards.

[André Mermoud]

As a general definition:

Efficency = Pmpp [W] / (Incid. Irrad [W/m2] * Ref area [m2]).

The reference area may be either the module area (usual module efficiency) or the sensitive area (which will give a "cell" efficiency, more related to the technology).

In the specific case of the STC efficiency mentioned on the loss diagram:

- Irrad = 1000 W/m2

- Pmpp = Impp * Vmpp issued from the application of the model at 25°C