On the impact of climate change on the thermal energy demand for a building: an analysis based on 50 years of meteorological data

Abstract

Despite the importance of buildings’ energy consumption as a significant contributor to carbon emissions, there is currently a lack of analysis on the impact of climate change on a building’s energy consumption using experimental data. This paper’s main goal and novelty are to determine whether, over 54 years from 1970 to 2023, the net energy demand of a building has changed and to what extent. Within this framework, this paper presents a dynamic analysis of a building located in Milan, northern Italy. The building is served by a multifunctional heat pump for heating, cooling, and domestic hot water production, supplemented by a photovoltaic panel system covering part of the overall electricity demand. The overview of experimental climate data for the considered site from approximately the past 50 years shows significant variations, setting the stage for anticipating future environmental challenges and preparing adaptive strategies to mitigate the impact of climate change. As a result, the electricity demand has increased on average over the years, specifically showing a significant decrease in energy required for heating and an increase in demand for cooling. The overall increase in electrical energy demand for buildings and systems is 2.3%, from 6310 kWh in 1970 to 6460 kWh in 2023. By considering the contribution of the PV, overall, the net energy demand of the building, coupled with the multifunctional heat pump and the extensive PV panel system, results in a 9.2% reduction in net electrical energy required from the electrical grid, from 2170 kWh in 1970 to 1990 kWh in 2023.

Keywords

Energy demand / Climate change / Dynamic simulation / HVAC / Air-source heat pumps / Recuperators / PV panels

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Funding

Alma Mater Studiorum - Università di Bologna

RIGHTS & PERMISSIONS

The Author(s)