Question: I am designing a hybrid PV-Diesel system with storage. I have a question concerning the simulation results. The renewable fraction shows 34% while the portion of energy supplied by PV represents 40% of the total load. I am using load following dispatch strategy in the simulation.

Answer:

The energy supplied is independent of the load. It is calculated entire on energy production, regardless of whether it serves the primary load. The renewable fraction is based on the amount of the renewable energy that goes towards serving the primary load.

Many times, these numbers will be the same, but in systems where there is a lot of excess renewable energy production, the portion of energy supplied from renewable sources will be greater than the renewable fraction.

The renewable fraction is the fraction of the energy delivered to the load that originated from renewable power sources.  The renewable fraction equation can be found in the built-in help in the HOMER software.