  Citation: Vivian, J.; Chinello, M.; Zarrella, A.; De Carli, M. Investigation on Individual and Collective PV Self-Consumption for a Fifth Generation District Heating Network. Energies 2022, 15, 1022. https://doi.org/10.3390/en15031022 Academic Editor: Dorota Chwieduk Received: 11 December 2021 Accepted: 28 January 2022 Published: 29 January 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). energies Article Investigation on Individual and Collective PV Self-Consumption for a Fifth Generation District Heating Network Jacopo Vivian 1,2, * , Mattia Chinello 1,3 , Angelo Zarrella 1 and Michele De Carli 1 1 Department of Industrial Engineering, University of Padua, 35131 Padua, Italy; m.chinello@casateam.it (M.C.); angelo.zarrella@unipd.it (A.Z.); michele.decarli@unipd.it (M.D.C.) 2 Urban Energy SystemsLaboratory, EMPA Materials Science and Technology, 8600 Dübendorf, Switzerland 3 CASATEAM Srl., 31038 Paese, Italy * Correspondence: jacopo.vivian@empa.ch; Tel.: +41-58-765-4185 Abstract: Renewable Energy Communities have been recently introduced in European legislation to promote distributed generation from renewable energy sources. In fact, they allow to produce and consume energy from shared local power plants. Low temperature district heating and cooling networks with distributed heat pumps have demonstrated their capability to exploit renewable and waste heat sources in the urban environment. Therefore, they are considered a promising infrastructure to help decarbonize the building sector. As their main operating cost is the electricity purchased by the utility for heat pumps and circulation pumps, this work investigates whether a Renewable Energy Community could help mitigate such cost by sharing electricity produced by local photovoltaic (PV) systems. The research relies on computer simulations performed with both physical and statistical models for the evaluation of electrical load profiles at the district level. Results show that due to the different seasonality between heating demand and PV production, the increase in self-consumption due to the distributed heat pumps is lower than 10%. The use of batteries does not seem convenient for the same reason. The environmental benefit of the proposed system is evident, with CO 2 emissions reduced by 72–80% compared to the current situation depending on PV power installed. It also emerged that PV sharing significantly improves the self-consumption at the district level, in particular when the installed PV power is limited (+45%). In conclusion, results suggest that current incentives on PV-sharing make Renewable Energy Communities a viable option to improve the techno-economic performance of fifth-generation district heating and cooling networks. Keywords: Renewable Energy Community; PV; district heating and cooling; heat pumps; collective self-consumption 1. Introduction Recently, the Renewables Energy Directive introduced a legal framework for Renew- able Energy Communities (RECs), i.e., cooperative organisations for the development of local energy initiatives with non-commercial purposes. The shareholders or members of the REC may be natural persons, small medium enterprises or local authorities, including municipalities, whose primary purpose is to provide environmental, economic or social community benefits rather than financial profits [1]. According to Koirala et al. [2], Energy Communities (EC) help re-organize local energy systems to integrate distributed energy resources, engage local communities and at the same time provide useful services to the larger energy system. As pointed out by Ceglia et al. [3], smart energy communities are essential to build a sustainable renewable energy system, which is based on a cross-sectoral approach and which seeks the optimal solution from an energy, environmental and economic point of view. Energies 2022, 15, 1022. https://doi.org/10.3390/en15031022 https://www.mdpi.com/journal/energies