Overview: The inter-municipal DH network along the Weiz-Gleisdorf axis represents a significant collaborative initiative by the suppliers from the municipalities of Weiz, Unterfladnitz, St Ruprecht, Wollsdorf, and Gleisdorf. The involved partners are actively pursuing the formation of a network association aimed at exploiting the substantial potential for integrating locally available renewable energy sources into the regional energy infrastructure. Currently, concepts are being developed to merge the distinct district heating systems of these municipalities into a unified, intercommunal network. This integration is expected to increase heat generation capacities significantly.

Current DH system: The axis is around 77km long and supplies heat to approximatelly 1.200 customers. The district heating system along the Weiz-Gleisdorf axis has a diversified portfolio of heat generation technologies, primarily harnessing renewable and locally available resources. The total installed thermal capacity across the towns encompasses wood chip boilers with a cumulative capacity of 33.9 MW_th, solar thermal installations contributing 1.9 MW_th, industrial waste heat recovery systems accounting for an additional 12 MW_th, and one bio-oil boiler with a capacity of 10 MW_th. Complementing these renewable-based systems, fossil fuel-based plants include two oil boilers with 10 MW_th and natural gas boilers totalling 3.0 MW_th. Furthermore, a heat pump system utilising thermal energy from wastewater treatment contributes an additional 0.8 MW_th to the supply portfolio.

Based on operational data from the year 2023, these generation assets collectively supplied approximately 100 GWh of thermal energy to the local district heating networks.

What work will ENABLE DHC do?: The envisaged integration of currently independent DH networks along the Weiz-Gleisdorf axis needs the implementation of comprehensive upgrading measures, following a holistic and systemic approach. For this, the ENABLE DHC project will use GIS-based planning and thermohydraulic simulations to evaluate available sources of renewable heat, such as waste heat, geothermal, and the integration of future plants based on large-scale heat pumps and solar thermal energy coupled with heat storage options. This investigation will allow the grid to be considered efficient under the Energy Efficiency Directive of the EU and allow the system to expand. The operator foresees an expansion of the grid to more than 70% of its current size.

Partners involved: AEE Intec