Feasibility analysis of integrating solar thermal technologies into district heating network with urban building energy modeling

The aim of this work is to study the effects of utilizing cleaner technologies in district heating networks and assess their contribution to the energy transition within densely populated urban areas. In this context, this study presents a methodology using Urban Building Energy Modeling (UBEM) with a place-based approach to assess the potential of integrating solar thermal collectors for space heating and hot water production services. Moreover, it compares their feasibility with photovoltaic panels. The proposed methodology can be applied to various urban contexts with different climate conditions using an open-source tool and available databases. The methodology adopts a bottom-up approach with a building as the territorial unit, and it takes into account site specific climate condition, building characteristics, urban features, and local constraints. The key step presented in this work is a detailed roof segmentation method used to evaluate the available areas on different roof orientations. The results show an increase in self-consumption and self-sufficiency levels when solar production is utilized for multiple energy services compared to a single service. This increase is three-fold in self-consumption index when hot water is added to the space heating service (a rise from 10% to 31%), and double for self-efficiency index, that is, from 12 to 24%. By using energetic, economic and social indicators, this study contributes to defining target indicators and indexes, while considering local constrains, to achieve the overarching goal of sustainability in energy system. This is aligned with the efforts that are being made to create sustainable cities through collective actions.