Comparative Analysis of Energy Yield between PERC and HJT Modules Tested in Experimental Campaigns Carried out in Northern Italy

The heterojunction (HJT) solar cells based on the integration of monocrystalline silicon and amorphous crystalline layers provide a remarkable improvement in terms of efficiency with respect to the Passivated Emitter and Rear Cell (PERC) modules, which are currently installed in most of plants. However, the efficiency gain in terms of energy production is not estimated by recent works in literature for the Mediterranean area: hence, this paper presents a comparative study of energy yield in Torino (latitude of 45° North, Italy) between PERC and HJT modules currently available on the market for conventional PhotoVoltaic (PV) installations, having rated power higher than 400 W. The modules were tested in experimental campaigns taking place in 2023 from April to September. In particular, this work quantifies the real energy yield improvements of HJTs with respect to PERC PV modules, resulting in an energy gain of HJTs between 3% and 6%. Finally, the dependence of these energy yield gains on irradiance and modules' temperature is investigated.