Efficiency for photovoltaic inverter: A technological review

It is recognized that a small percentage difference in the efficiency of a photovoltaic (PV) inverters causes a substantial variation in their cost. This is understandable because a PV inverter is expected to be in service for a good number of years (possibly as long as the PV modules themselves) and therefore the total energy yield that can be extracted using the inverter need to be considered in the initial investment calculation. However, there appears to be confusion on the real meaning of the term “inverter efficiency”. Unfortunately, there is no single documented reference available that can adequately describe the significant of these efficiencies and how are they related to each other. In most cases, the user only relies on the efficiency numbers stamped on the inverter nameplate as a guide during PV system dimensioning. Such approach may result in a non-optimized solution. This critical review paper is an attempt to clarify these confusions by gathering, organizing and analyzing the scattered information available around from various literatures. It is hoped that the information assembled in this paper can be a valuable guidelines for PV practitioners as well as researchers to kick start their research in this field.