RepsoLusim was an industrial research and innovation project carried out by LuciSun within the Repsol Foundation Entrepreneurs Fund. The project provided the opportunity to apply and test advanced 3D PV simulation approaches on a real, operating bifacial photovoltaic plant developed by Repsol, under realistic industrial constraints and with access to detailed field data. 

A central element of the project was the development of several successive prototypes of LuSim 3D and of digital twins built on top of these prototypes. These digital representations made it possible to analyse irradiance distributions at module and sub-module level, including the effects of complex shading, tracker geometry, structural elements and border effects, with a level of detail beyond that of standard engineering tools. 

Beyond technical development, RepsoLusim played a key role as a testbed for confronting advanced simulation concepts with industrial practice. Working closely with a large PV plant developer made it possible to identify the practical difficulties commonly encountered in the evaluation of bifacial PV plants, including data availability, modelling complexity, result interpretation and communication of added value. This feedback helped guide the evolution of LuSim towards solutions that are not only technically sound, but also usable and relevant in real project workflows. 

The project therefore provided both a technical validation of LuSim’s core modelling concepts and a business validation of its applicability to industrial bifacial PV projects. The lessons learned during RepsoLusim continue to inform LuciSun’s software development priorities, its approach to digital twins, and its technical advisory and training activities related to bifacial PV system design and performance assessment.