Investigating Measures on Space Heating and Domestic Hot Water Preparation Systems in Residential Buildings Regarding Their Impact on the Total Heat Demand and Return Temperatures in District Heating Networks
Abstract
District heating can contribute substantially to a cost-efficient and renewable heating sector by integrating renewable energy sources and surplus heat. The aim of this simulation study is to assess the impact of several measures on the space heating and domestic hot water preparation system in residential buildings on the total heat demand and return temperatures in district heating systems. For this purpose, two buildings, one single- and one multifamily house, that are both supplied by low temperature district heating with a supply temperature of 70 °C, have been modelled in the transient system simulation tool TRNSYS. For both buildings, two different energy efficiency standards have been considered. For space heating, different system designs, user behavior and control strategies are investigated. For domestic hot water preparation systems, different system designs, storage and pipe insulations, circulation controls are simulated. The resulting total heat demand and return temperatures are evaluated and used to design a thermal subgrid in Mannheim (Germany) as well as a guideline for heating systems in buildings.