Modeling Technology Retrofit Scenarios for the Conversion of Condominium into an Energy Community: an Italian Case Study

This work aims to investigate what kind of impact retrofit scenarios have on "building energy communities" in view of the European Union climate targets on CO2 emission reduction, energy efficiency, and the share of renewable energy. Data-driven retrofit scenarios have been simulated considering a condominium constituted by eighty-seven units, located in the North-West of Italy. Different technology mixes (including roof-top photovoltaic, air-source heat pump, battery energy storage, and electric vehicles chargers) supplying for the electric and head demands have been simulated. The techno-economic feasibility of each retrofit scenario has been evaluated along with its compliance with the EU climate target by a multi-criteria analysis. The retrofit with roof-top photovoltaic systems always leads to positive environmental and economic indicators. Besides, it also reaches the highest internal rate of return of 18.2%. The air-water heat pump helps in reducing the total primary energy demand of -26% and the CO2 emission of -30%. Nonetheless, it introduces electric load-volatility on the electric grid that appears to be even more challenging than the photovoltaic intermittency. This issue can be conditioned by installing a storage system smoothing the heat pump load-volatility. The charge of electric vehicles within the condominium also has a global positive effect as it increasing the self-consumption up to 9.5%. The multi-criteria analysis shows that the diffusion of condominium energy communities by itself does not guarantee the pursue of the European Union decarbonization roadmap. In fact, if the purpose of condominium energy communities is not well channeled to the citizen, by giving them other forms of incentives besides the economic ones, they might still opt for the economic benefit over the environmental one jeopardizing the potential benefit related to energy communities initiatives. (C) 2020 Elsevier Ltd. All rights reserved.