Shamrockpark Herne: Use of waste heat from data center and industry
Overview of the Shamrockpark District
Designing an efficient energy system for the Shamrockpark district in Herne, Germany, involves multiple challenges but also great potential, which makes it a perfect demo case for the energy transition as a whole. This also makes Shamrockpark an important part of a living lab for the energy transition ('Reallabor der Energiewende' in German) under the umbrella of the research project TransUrban.NRW with federal funding from BMWK. At heatbeat, we support the project by representing the buildings, the innovative 5th generation district heating and cooling network, and the heating and cooling generators in our heatbeat Digital Twin. With this contribution we support the this important project from the planning phase through the commissioning and also with the continuous optimization during the actual network operation.
Our interactive 3D representation shows the Shamrockpark district with buildings, generators and the thermal network. The white buildings represent the already existing buildings, while the blue colored buildings show the new buildings. With regards to the energy system it is important to consider that existing buildings and also new buildings are both supplied by the same low-temperature network.
The usage types of the buildings are heterogenous, having both residential buildings in the northern part of the district and many non-residential buildings with e.g. office spaces, a hotel, a canteen and a health center. From an energy system perspective, one crucial part is that the district also contains a data center on the site. The usage types can are also shown in our interactive map:
As a result, the energy system has to cover a large cooling demand. And at the same time, the cooling requirement of the data center offers a large waste heat potential. On top of that, being situated very close to a large industrial plant offers even more waste heat potential. Thus, the central challenge in this district is to make the best possible use of those potentials and other synergies in order to meet the building demands as efficiently as possible. For this purpose, the following figure shows an overview of the demands for space heating, domestic hot water and cooling:
Combining 5th generation district heating with waste heat utilization
The key challenge when using waste heat from industry and data centers is that although large amounts of waste heat are available in the district, this waste heat is only available at a low temperature level. Therefore, the central idea of the energy system in Shamrockpark is to use a bidirectional low-temperature district heating network as an energy platform. A warmer pipe at 22 °C allows heat sources with a low temperature level - such as waste heat from the data center and industry - to feed their heat directly into the network. At the same time, a cold pipe at 12 °C allows buildings to receive cooling directly from the network. For this, it is crucial that the network is understood as a bidirectional network. This means that the buildings can change the direction of the flow via decentralized pumps depending on the heating or cooling demand and are supplied either from the warm or from the cold pipe.
An important side effect of this bidirectional use of the network is that each heat withdrawal from the warm pipe simultaneously returns a cooling potential to the cold pipe of the network. At the same time, each building in cooling mode using the cold pipe returns the excess heat into the warm pipe of the network, generating a waste heat potential. This also means that there is a great potential for synergies. If there are simultaneous heating and cooling demands in the network, these can balance themselves out within the network. And since with the data center there is a large continuous cooling demand in the network also during the heating period, the Shamrockpark system offers very favorable conditions for such an energy concept.
In order to be able to serve the temperature demands of the buildings despite the low temperature level in the network, the substations of the buildings also contain decentralized heat pumps. And since the source temperature for the heat pumps with the network at 22 °C is very favorable for the efficiency of the heat pumps, in this case the existing buildings with higher temperature demands in the building of 60 - 65 °C can also be supplied efficiently via the heat pumps.
Evaluation of network operation and waste heat utilization
Due to the complex interaction between heating and cooling demands, the resulting dynamic network behavior, and the interactions between decentralized heat pumps and the network, a system evaluation and optimization is not possible based on simple empirical benchmarks. Therefore, we support the project with dynamic simulations using our heatbeat Digital Twin. This yields a very detailed representation of the network operation and enables an accurate evaluation of the the overall system efficiency.
To illustrate this, the following animation shows the network operation over the course of a day with a high heat load in the network. The line thickness in the network illustrates the respective volume flow. This shows how a large part of the district is supplied by the waste heat from the data center during lower loads while the main supply has to cover more of the peak loads.
In addition, the following Sankey diagram clearly shows the large impact of synergies between heating and cooling demands in the network. As a result, it can be seen that with this energy concept, only a small amount of industrial waste heat needs to be brought into the system to cover the heating demands, since so much waste heat from the data center is recycled directly within the network itself. And also for covering the cooling demands, the operation of the compression chillers in the data center and the main supply is significantly reduced due to the synergies. Thus, the Shamrockpark example shows very impressively what potentials can be gained by a detailed optimization of the energy concept for the heating and cooling supply of a district.
For this project, we would like to thank our project partners for the great cooperation and especially the Federal Ministry for Economic Affairs and Climate Action for funding the project. Should you need any more general information about the Shamrockpark or if you are interested in our other projects under the umbrella of the research project TransUrban.NRW you can inform yourself further here.
