On one side, the capacity of the world’s photovoltaic (PV) systems is experiencing unprecedented growth; on the other side, the number of connected devices is rapidly increasing due to the development of advanced communication technologies. These fields are not completely independent, and recent studies show that indoor energy harvesting is a great candidate for answering the energy challenges of future generations of telecommunications, namely 5G and 6G, ideal for internet-of-things (IoT) scenarios, i.e., smart homes, smart cities, and smart factories. The emerging PV technologies have shown amazing capabilities for indoor energy harvesting, displaying high power conversion efficiency, good flexibility, and champion-specific powers. Recently, the excellent dynamic performance of PV devices enabled them to be used as data receivers in optical wireless communication (OWC) scenarios, calling forth an innovative system able to simultaneously harvest energy and receive communication data with a single PV device. This article reviews the recent literature devoted to the exploitation of photovoltaic technologies for simultaneous indoor energy harvesting and OWC data reception. This contribution highlights the strong potential of the approach toward the next generation of Green IoT systems and the current challenges that need to be addressed with regard to the physics of solar cells, from laboratory to large-scale applications.
The massive deployment of IoT connected devices brings up different modern problems, such as radiofrequency spectrum saturation and energetic requirements. Organic photovoltaics are good candidates for indoor energy harvesting and data reception in a simultaneous lightwave information and power transfer scenario applied for IoT, at which the non-directive channel significantly contributes to the optical system performance. However, achieving the channel impulse response of diffuse links requires complex numerical approaches. This article presents the first ever OPV model used in a Monte-Carlo ray-tracing simulation, associated to theoretical and experimental validation. Finally, for the first time, an optical simulation with an OPV receiver is realized in a cubic environment, from which the received optical power and generated current distributions were obtained. Results show that the employed OPV is suited for indoor energy harvesting to supply low power IoT nodes, and with proper dedicated front-end, could manage to receive optical data in a SLIPT scenario.
15 December 2022 in Les Journées de L'interdisciplinarité
Dans un monde technologique en pleine mutation, le nombre d’appareils connectés explose et le domaine des télécommunications doit suivre le rythme en offrant une connectivité toujours plus robuste et fiable, tout en assurant une emprunte énergétique la plus faible possible. Les nouvelles générations de technologies sans fils mobiles (la 5G aujourd’hui et la 6G demain) cherchent ainsi à exploiter de nouvelles bandes de fréquences pour éviter la saturation du spectre radiofréquence (RF) actuel. Dans ce contexte, la communication sans fil par voie optique (Optical Wireless Communication - OWC) est une solution notamment pour les environnements intérieurs. D’autre part, l’utilisation de cellules et modules photovoltaïques pour la récupération d’énergie ambiante est étudiée actuellement pour la réception de données par voie optique. Ce concept récent associant des expertises interdisciplinaires dans les domaines de l’énergie et des télécommunications permet d’envisager l’alimentation en énergie des dispositifs communicants de l’internet des objets (IoT), tout en leur apportant une fonctionnalité de réception OWC. Ce travail décrit ainsi les principes de base de la technologie OWC et propose un état de l’art synthétique sur l’utilisation de photorécepteurs photovoltaïques pour cet usage innovant.