Source: Energy & Management Powernews, 06 May 2022
Municipal heat planning is driving many municipalities as well as municipal utilities. It could accelerate the necessary heat turnaround with renewable sources. But there are still many open questions.
The potentials with renewable heat sources, heat pumps, but also renewable CHP and geothermal energy in urban areas are high - however, there are also still many open questions to be clarified, as was shown at an event at the Berlin Energy Days. "There are still fundamental questions to which we need answers," said Christian Maaß, head of the Heat, Hydrogen and Efficiency Department at the German Federal Ministry of Economics and Technology (BMWK), on May 5 at the virtual roundtable "Heat pumps thought urban - energy research for the heat turnaround."
How can decentralized heat technologies be integrated into existing buildings? Will there be conflicts in groundwater protection if technologies such as heat pumps and geothermal systems are increasingly installed? In order to find answers to these questions quickly, the BMWK is focusing more on energy research. Maaß emphasized that more funding should flow in the future, for example for urgently needed pilot projects that put ideas and approaches into practice.
Such pilot projects already exist, and some were presented at the Berlin Energy Days. If a large number of buildings in a quarter or a settlement are to be supplied with regenerative heat, this is best done via a heat network. But connecting existing buildings in particular is not technically trivial. That's why it's important to experiment in practice with which combinations of heat sources work in individual quarters, said Jörg Friedrich Paulus, sales manager at Avacon Natur. His company is currently testing new concepts in four neighborhoods in North Rhine-Westphalia - via the "TransUrban.NR" real laboratory.
The project is being implemented by several companies such as Eon and Avacon, as well as partners from municipal companies, the real estate industry and research such as the University of RWTH Aachen. The technology used is low-temperature networks. While classic district heating networks are often operated at temperatures of more than 100 degrees Celsius, 10 to 40 degrees Celsius are sufficient for the "LowEx" networks. Heat pumps in the buildings raise the temperatures or generate cooling energy. Transurban NRW is testing how the integration of renewable energies such as geothermal energy or the use of waste heat can also succeed in existing buildings and how a competitive market can emerge from this. This also requires "new digitization concepts," Paulus emphasized, which are also being tested.
More energy research needed for heat transition
Another example can be found in Oberhausen. Together with the Oberhausen municipal utility, the Fraunhofer Institute Umsicht has modernized several quarters with many existing buildings. In the future, a combined heat and power plant will supply the heat in each neighborhood via a local heating network. In order to keep consumption as low as possible and be able to react flexibly to the energy markets, the "Quentin" project is testing whether a central storage unit plus other smaller storage units in the buildings offer added value in terms of efficiency and cost-effectiveness. The researchers hope to gain important new insights here as well in the coming months.
At the same time, however, municipalities are under immense pressure to act if they want to achieve climate targets, said Anne Hagemeier, also of the Fraunhofer Institute for Foresight. This is where "municipal heat planning" is intended to help create clarity about the path of individual regions toward climate neutrality. Gordon Appel from Stadtwerke Konstanz sees a major advantage in the binding nature of such heat planning. The public utilities have already gained experience with it, since in Baden-Wuerttemberg the heat planning is already obligation.
The local heat planning is to be converted after the plans of the traffic light coalition in the future surface covering. The task spectrum within the heat planning is broadly varied. These include the creation of heat registers, the monitoring of heat network expansion, the decarbonization of existing networks, the securing of areas for energy generation and for energy storage, as well as concepts for the renovation of public buildings.
Municipal heat planning is, however, a relatively new political instrument for which acceptance must be created. "Therefore, for a nationwide introduction, it is crucial that the framework conditions are significantly improved. This includes, for example, comprehensive financing and attractive consulting services," emphasized VKU CEO Ingbert Liebing at the Berlin Energy Days. In addition to the planning activity, the investment conditions for the conversion of the various supply infrastructures on site would have to be improved at the same time and the technology openness on site would have to be preserved.
Author: Heidi Roider
