RELaTED innovative technologies for district heating systems

RELaTED will integrate present technologies into a new ULT DH concept, at distribution temperatures below commercially operative DH networks today.

The development towards “nearly zero-energy buildings” (combined net consumption of space heat and domestic hot water < 40 kWh/m²), and the extension potential of district heating networks into less populated areas with reduced heat density has led to the development of low temperature district heating (LT DH) systems. The main objectives of LT DH have been to reduce distribution heat losses and investment costs, as well as ease the uptake of renewable and residual energy sources in the networks.

With the progressive reduction of district heating supply temperature, an increased number of heat production technologies can be incorporated into district heating systems, and technical limits to the incorporation of many RES and waste heat sources are reduced, allowing for the decarbonisation of the energy supply.

With the progressive reduction of district heating supply temperature, an increased number of heat production technologies can be incorporated into district heating systems

RELaTED will integrate present technologies into a new ULT DH concept, at distribution temperatures below commercially operative DH networks today.

The main innovation in RELaTED is the concept itself, where lower distribution temperatures are paired by a set of innovative technologies enabling for the rearrangement of DH networks into a collection of energy hubs, not only with local heat consumption but also the heat production, based on the following technologies:

• 3FS systems will upgrade the concept of consumer substations into elements where bidirectional heat flow is allowed between among three subsystems and the DH network with net metering & energy billing:
• Building integrated ST systems (BILTST)
• Heating applications (potentially district heating integrated renewable heat pump, DHRHP)
• Reject heat reuse from cooling applications (potentially integrated via district heating integrated renewable heat pump)
• BILTST systems will adapt traditional Solar Thermal systems for building integration into configurations compatible with DH, without further need of local heat storage, and the capacity to inject heat into the grid.
• DHRHP systems will adapt low-temperature DH operation with higher distribution temperatures within HVAC systems in buildings, particular technical applications of heat, and possible heat recovery from cooling applications.