The Role of Industrial Excess Heat for the Transformation of the Energy System

Abstract In Austria, heat supply accounts for more than half of the country’s final energy consumption, with low-temperature heat below 100 °C for space heating and domestic hot water making up around 61% of that. Approximately 47% of total heat consumption is still covered by fossil energy sources. In the energy-intensive industrial sector in particular, previously unused excess heat is available for cascading use. This publication presents industrial excess-heat potentials identified through individual case studies and a nationwide survey. According to the comparison of figures, in an ideal scenario roughly 65% of private space heating consumption could be covered by excess heat. In addition to conventional district-heating systems, which represent the current state of the art, new options are emerging for distributing excess heat, including supra-national district-heating networks for longer transport distances. For challenges associated with predominantly low temperatures, mature and proven solutions exist through the combination of heat pumps and anergy networks. Increasing the integration of excess heat is absolutely essential in order to raise the efficiency of industry and further decarbonize the heating sector.