The Impact of Optimal Demand Response Control and Thermal Energy Storage on a District Heating System

Sonja Salo,Aira Hast,Juha Jokisalo,Sanna Syri,Risto Kosonen,Janne Hirvonen,Kristian Martin

doi:10.3390/en12091678

Abstract

Demand response has been studied in district heating connected buildings since the rollout of smart, communicating devices has made it cost-effective to control buildings’ energy consumption externally. This research investigates optimal demand response control strategies from the district heating operator perspective. Based on earlier simulations on the building level, different case algorithms were simulated on a typical district heating system. The results show that even in the best case, heat production costs can be decreased by only 0.7%. However, by implementing hot water thermal storage in the system, demand response can become more profitable, resulting in 1.4% cost savings. It is concluded that the hot water storage tank can balance district heating peak loads for longer periods of time, which enhances the ability to use demand response strategies on a larger share of the building stock.

Highlights

Smart energy systems can support the mitigation of climate change cost-effectively
The results indicate that an increase in load variation does not necessarily mean an increase in district heating (DH) production costs
As summer-time heat demand consists almost only of includes connected to the location and temporal aspect associated with consumption, domestic hot water (DHW), the thermal store content of each case does not differ from the reference case

Summary

Introduction

Smart energy systems can support the mitigation of climate change cost-effectively. Mathiesen et al [1] describe smart energy systems as the ultimate concept of deploying 100% renewable energy sources to the energy system. District heating (DH) is a mature technology and combined heat and power (CHP) is deemed as a conventional energy source, there is still demand for operating them to their full extent because of their indispensable role in the energy sector. One of the main challenges in the operation of DH systems is the occasionally significant variations in heat load, which result in part-load operation and frequent start-ups and stops for heat generation units [4]. Integrating TES systems into DH networks can improve the balance between the heat load and supply, thereby decreasing the demand for high-cost marginal generation

Methods

Results

Conclusion