In order to achieve the ambitious objectives set by the European Union for the climate and energy goals, a transition towards a future sustainable energy supply is needed. The integration of the huge potential for industrial waste heat recovery into Smart Energy System (SES) represents a main opportunity to accomplish these goals.
To successfully implement this strategy, the adoption of a system approach is required, since all the several stakeholders’ conflicting objectives should be considered. To address this challenge, in this paper an evolutionary multi-objective optimization model is developed to perform a sustainability evaluation of a SES involving an industrial facility as the waste heat source and the neighborhood with different characteristics and activities (residential, commercial, and institutional) as potential users by a district heating network, in the typical European city brown field context.
The model has been applied to an Italian case study, analysing heat recovery from a steel casting facility to satisfy the heating needs of the southern part of Udine Municipality through the realization of a district heating (DH) network. Different DH layout scenarios have been analysed, to consider the connection of the main current and future city areas and different clients.
Energy system modelling has been implemented in MATLAB®, while the genetic multi-objective optimization has been performed by modeFRONTIER®, which allows to mark the Pareto front of solutions and the Multi Criteria Decision Making (MCDM) post processing analysis.
Results show that the developed model allows to properly select the DH network set of users and system layout to fully exploit the available waste energy, in particular how involving a large and heterogeneous basin of clients leads to remarkable economic and environmental performances. Design configurations such as the best compromise for thermal energy storage capacity are also provided. Moreover, the multi-objective model enables the analysis of the trade-off between the stakeholders’ different perspectives, allowing to identify possible win-win solutions for both the industrial sector and the citizenship
