Energy sustainability and networking are the two main pillars on which the smart cities of the future will be based, with intelligent and networked energy devices fully integrated into buildings, capable of complying with strict regulations and having a minimal energy impact. In this context, in a paper published in the journal Advanced Energy Materials, the team of researchers from the University of Milano-Bicocca and CNR-Ino, in collaboration with Glass to Power SpA and LENS, has created and studied the first example of a photovoltaic window that is also equipped with the ability to exchange data through light, using VLC (Visible Light Communication) technology.
"The device has been created using new quantum dot luminescent solar concentrators, complies with all international regulations on photovoltaic and building elements, and has been characterised in terms of solar conversion energy yield according to the highest international standards," explains Sergio Brovelli, lecturer at the University of Milan-Bicocca and Chairman of the Scientific Board of Glass to Power SpA.
"The 'hybrid' window developed has a double function: it is used not only as a photovoltaic element for converting solar energy into electricity, but also, for the first time, as an effective system for receiving wireless data encoded as intensity modulation in the light emitted by conventional LED sources, at frequencies imperceptible to the human eye, using VLC technology", continues Jacopo Catani, one of the CNR-Ino researchers.
The use of white LED sources for both data communication and lighting is also known as Light Fidelity (Li-Fi). The device can operate as a VLC receiver even in direct sunlight, combining energy functions and wireless connectivity into a realistic solution for smart and sustainable buildings. The ability to generate power by harvesting sunlight or artificial light while transmitting data also opens up the possibility of creating self-powered smart devices that can exchange data pervasively and sustainably without significant impact on energy or human health.
This breakthrough is an important step towards the sustainable and green use of optical technologies in smart cities and the realisation of the Internet of Things (IoT) and the revolution promised by sixth generation (6G) communications systems.
The factsheet
Who: University of Milan-Bicocca, National Institute of Optics of the National Research Council of Sesto Fiorentino (CNR-Ino), Glass to Power SpA, European Laboratory of Non-Linear Spectroscopy of Sesto Fiorentino (Florence)
What: F. Meinardi*, F. Bruni, C. Castellan, M. Meucci, A. M. Umair, M. La Rosa, J. Catani*, S. Brovelli*, Certification Grade Quantum Dot Luminescent Solar Concentrator Glazing with Optical Wireless Communication Capability for Connected Sustainable Architecture Advanced Energy Materials (February 2024), Research link: https://doi.org/10.1002/aenm.202304006
All acknowledgements and references to the funded projects can be found in the publication.