Heating & cooling

Heating networks are an important pillar of decarbonisation in the heating sector. Due to the targeted grid expansion and the growth of urban areas, grids often reach their limits in terms of heat source availability and pipe capacity. The decarbonisation of heating networks themselves is just as challenging, but is made considerably easier by reducing network temperatures.

Heat pumps can make an important contribution to the expansion of grids. They can utilise the return flow of the heating network as a heat source and thus increase the heat output of the network by lowering the return flow temperature without increasing the pipe dimensions. The heat can be fed into the flow or supplied directly to consumers.
Lowering the network temperatures with the aim of reducing heat losses and/or integrating all types of waste heat, with or without a heat pump, often has narrow limits because some consumers could then no longer be supplied. This is where local heat pump boosters can help.

In addition to space heating, space cooling is also becoming increasingly important. If, as is usually the case, no district cooling network is available, waste heat from local cooling generation can at least be made available as a heat source for heating networks and thus primarily support the base load, e.g. hot water, which is then brought to the required temperature with local booster heat pumps.
Despite their high potential, heat pumps in heating networks and the utilisation of waste heat from room cooling for heating networks have hardly been researched and are rarely used, as there is often a lack of knowledge about the proper use of heat pumps.

This project will systematically analyse the success factors and restrictions of heat pumps in heating networks and the integration of waste heat from room cooling into heating networks and thus contribute to the expansion and greening of heating networks and to the reduction of losses in networks. To this end, six network types are defined in cooperation with Austrian heating network operators, in which the challenges described in (reduction of the network temperature, network expansion or integration of waste heat from room cooling) are analysed. Heat pump systems are dimensioned for all six network types and an alternative variant (alternative approach to cover demand or status quo) is also analysed in each case. For all network types, both variants are compared from a techno-economic perspective as well as in terms of energy savings and GHG reduction.

For the two grid types with the highest practical relevance, savings and good feasibility, comparable areas in Austria are identified, on the basis of which the analyses are concretised. Implementation barriers such as property rights aspects, noise emissions or existing infrastructures are also considered, focussing on differences between the heat pump variant and the reference variant. Based on the studies, system dimensioning is carried out, including calculation of the economic and ecological effects in comparison to the reference situation.

Particular attention is paid to the optimal integration into the existing network structures, as well as the optimisation of the coefficients of performance of the heat pumps. Furthermore, barriers, opportunities and economic success factors are analysed and recommendations for action and planning guidelines are formulated. The recommendations are formulated in a strategy paper and communicated to stakeholders via suitable information channels.

Client / Funding organisation	FFG, MA20
Project management	Franz Zach
Project team	Christoph Kurfürst
Project partners	Armacell Austria GmbH Ochsner Process Energy Systems GmbH
Project duration	November 2024 to October 2027