This article reviews the challenges confronted by such integration, investigating the technical and non-technical difficulties associated with the exploitation of solar thermal, waste heat, geothermal, and biomass energy sources into district heating systems.
In district heating (DH) systems, the time of use of energy is becoming more important. For example, the use of sustainable baseload units over peak units is favored. Also heat production units coupled to the electricity grid, such as cogeneration plants and heat pumps, can profit from fluctuating prices and balance the electricity network at the same time.
For decades the focus of district heating (DH) has been on energy efficiency and minimum operating temperatures. This quest for continuous efficiency improvements led to the modern 4th generation of DH (4GDH), operating at lowest possible temperature for direct utilization by end-user.