Cold Network Dollnstein
The market town of Dollnstein in the Eichstätt district wanted to reorganize and restructure the energy supply for the town center, known as the “Innerer Markt.” This gave rise to the idea of implementing the supply via a local heating network. The special feature here is that it is a Heat Network 4.0, i.e., a cold network.
Local heating network
The local groundwater is tapped via a well as a heat source. The groundwater has a year-round temperature of around 10°C and ultimately serves as a heat source for the building’s supply. In order to raise the heat to heating level, this project takes a two-pronged approach. During the transition period and the summer months, a solar thermal system in combination with a central CO₂ heat pump with a capacity of 440 kW generates the necessary heat energy.
The temperature of the network during these periods is approximately 30°C. In order to generate the required temperature in the buildings, transfer stations with integrated heat pumps are installed at each connection point. In addition, each building has a daily storage tank, designed as a buffer or stratified storage tank. This allows for greater flexibility of the entire energy generation system – the focus here is on generating energy from renewable sources. During the winter months, a CHP unit supplies the buildings centrally via the existing heating network in the traditional manner, with water at a temperature of approximately 75°C. The decentralized heat pumps are deactivated and a traditional transfer station for local heating integrated into the heat pump takes over the heat transfer.
The entire system is monitored by specially developed control technology software (SiMon), which processes all information from the neural network in the heating center and constantly optimizes the entire network with the help of artificial intelligence (AI). This makes it possible, for example, to use the weather forecast for generation forecasting. SiMon also analyzes the consumption behavior of individual users in this context and can thus give priority to renewable energies (sun for solar thermal energy) in generation wherever possible. The project was declared a flagship project by the KUMAS environmental network in 2015 and is still undergoing intensive scientific supervision and evaluation with federal funding.
