Technical Planning of Low Temperature District Heating Networks

The planning of new District Heating Networks (DHNs) and the retrofitting of existing ones is a complex process that involves multidisciplinary approaches and teams. This chapter presents technical planning of Low Temperature District Heating (LTDH) networks, which needs to be implanted together with energy and economic planning to successfully achieve a massive uptake of LTDH developments. Since the number of existing networks is high, the chapter also refers to the conversion of existing DHNs into LTDH networks to improve the performance and increase the share of low carbon heat sources. The technical approach to DHN conversion is very relevant, as each network is unique with regards to its network topology, temperature levels, buildings installations, status, tariff structure, management etc. The chapter presents specific examples of District Heating (DH) topologies; use of simulation tools for the technical planning and design; considerations for operational temperature definition; interventions in sub-networks; hydraulics and building installations; phase-wise deployment of LTDH concepts; and supervision tools to ensure the proper development. The development of a real LTDH network is used as reference to better illustrate and further detail the main concepts presented.