Title: Electrified district heating networks: a thermo-economic optimisation based on exergy and energy analyses

Authors: Getnet Tadesse Ayele; Mohamed Tahar Mabrouk; Pierrick Haurant; Björn Laumert; Bruno Lacarrière; Massimo Santarelli

Addresses: GEPEA, Department of Energy Systems and Environment, IMT Atlantique, F-44307 Nantes, France; Department of Energy Technology, KTH Royal Institute of Technology, 100-44 Stockholm, Sweden ' GEPEA, Department of Energy Systems and Environment, IMT Atlantique, F-44307 Nantes, France ' GEPEA, Department of Energy Systems and Environment, IMT Atlantique, F-44307 Nantes, France ' Department of Energy Technology, KTH Royal Institute of Technology, 100-44 Stockholm, Sweden ' GEPEA, Department of Energy Systems and Environment, IMT Atlantique, F-44307 Nantes, France ' Dipartimento di Energetica, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy

Abstract: This paper presents a thermo-economic optimisation of an electrified district heating network consisting of wind power plant, gas-fired combined heat and power plant and heat pumps. The load flow problem of the resulting multi-energy system is formulated by considering all physical and operating parameters in both of the electricity and heat distribution networks. First, energy and exergy analyses are applied to identify and isolate lossy branches of a meshed heating network. This is followed by the optimal placement of heat pumps. Finally, supply and return temperatures are optimised. Particle swarm optimisation technique is implemented in order to find the best place of heat pumps, their economical dispatch and optimal temperature profile of the district heating network. Results show that up to 59.12% of the distribution heat loss and 9.37% of the operating cost can be saved by following a step-by-step methodology discussed in this paper.

Keywords: combined heat and power flows; combined heat and power; CHP; district heating network; DHN; electrified district heating network; energy hubs; exergy; heat pumps; lossy branch identification; multi-energy systems; MESs; optimal placement; thermo-economic optimisation; particle swarm optimisation; PSO.

DOI: 10.1504/IJEX.2021.115088

International Journal of Exergy, 2021 Vol.35 No.1, pp.100 - 131

Received: 11 Dec 2019
Accepted: 11 Jul 2020

Published online: 06 May 2021 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article