energies Review The Challenge for Building Integration of Highly Transparent Photovoltaics and Photoelectrochromic Devices Alessandro Cannavale 1,2,* , Francesco Martellotta 1 , Francesco Fiorito 3 and Ubaldo Ayr 1 1 Department of Sciences in Civil Engineering and Architecture, Polytechnic University of Bari, 70125 Bari, Italy;
[email protected] (F.M.);
[email protected] (U.A.) 2 Istituto di Nanotecnologia, CNR Nanotec, Via Arnesano 16, 73100 Lecce, Italy 3 Department of Civil, Environmental, Land, Building Engineering and Chemistry, Polytechnic University of Bari, 70125 Bari, Italy; francesco.fi
[email protected] * Correspondence:
[email protected]; Tel.: +39-080-596-3718 Received: 19 March 2020; Accepted: 10 April 2020; Published: 14 April 2020 Abstract: This paper holds a critical review of current research activities dealing with smart architectural glazing worldwide. Hereafter, the main trends are analyzed and critically reported, with open issues, challenges, and opportunities, providing an accurate description of technological evolution of devices in time. This manuscript deals with some well-known, highly performing technologies, such as semitransparent photovoltaics and novel photoelectrochromic devices, the readiest, probably, to reach the final stage of development, to disclose the manifold advantages of multifunctional, smart glazing. The complex, overall effects of their building integration are also reported, especially regarding energy balance and indoor visual comfort in buildings. Keywords: semi-transparent photovoltaics; photoelectrochromic devices; photovoltachromic devices; building integration of photovoltaics 1. Introduction The progressive exhaustion of fossil fuels and the consequent biosphere alteration are strictly related to the dramatic growth of energy consumption. Global warming witnesses the effects of anthropic activities on the biosphere. In 2015, during the Conference of Paris, representatives of 196 countries agreed on the urgency to reduce the impacts of human activities [1].