Low-temperature district heating consumer substations in multi- and single-family buildings

The report starts with presenting benefits on low-temperature DH on heat production of the DH networks. It continues with analyses comparing traditional four pipes heating system and system with flat stations in multi-apartment buildings and ends with possible solutions for integration of on-site heat sources as solar-thermal collectors and waste-water heat pump.

It concludes that when designed properly, the system with flat stations results in lower heat loses from the in-house distribution system compared to traditional four pipe horizontal system.

In addition use of flat stations and acceptance of DHW with 45°C makes possible decrease the supply temperature from both DH network and on-site renewable sources by 10 °C compared to traditional systems with centralized DHW preparation and thus increase efficiency of district heating (DH) and renewable sources of energy (RES). For systems with traditional centralized heating of DHW the reduction of DHW to 45°C is not possible, due to big volume of DHW and possible stagnation points resulting in temperature drop and Legionella growth.

In the report are analyzed various solutions for integration of on-site produced renewable heat as solar thermal and waste-water heat pump. Pro and cons of each solution are discussed and preferable solution suggested for system with flat stations and also for traditional system with centralized production of DHW (four pipes system). In time of the report submission, there was not agreed across the partners which solutions will be exactly tested in Ringgården department 20 and 21.

Next phase of Ready project is implementation of traditional four pipes horizontal and flat stations system into very similar buildings, which will make possible validate the theoretical results presented in this report.

Want to know more?

Delivery no. D.3.2.1 Low-temperature district heating consumer substations in multi- and single-family buildings
Please contact: Mr. Marek Brand, Danfoss, marek.brand@danfoss.com