Optimization of a PV-wind-diesel hybrid system for a remote stand-alone application

Hybrid systems are an interesting solution for the electrification of isolated consumers, which often make use only of diesel generators. In particular, the possibility of including renewable energy sources, particularly wind and PV, is being increasingly appreciated. In the study, a sizing strategy, based on a long-term energy production cost analysis, was developed, able to predict the optimum configuration of a hybrid PV-wind-diesel stand-alone system, which was tested on an isolated mountain chalet in Italy. The system was optimized based on the maximum long-term saving with respect to a conventional diesel engine configuration. In particular, the optimal solution was not that including the maximum allowed contribution from renewables, highlighting the existence of an optimized energy mix between the three sources. Accumulation batteries were also able to induce a reduction of the fuel consumption and the engine transitory usage. According to the present results, a properly sized hybrid system could provide notable money and pollution savings for a remote consumer with respect to a diesel-only configuration.