Power-to-hydrogen & district heating: Technology-based and infrastructure-oriented analysis of (future) sector coupling potentials

Numerous studies suggest that power-to-hydrogen (PtH2) will take a decisive part in future sustainable energy systems. District heating (DH) networks are also assigned a crucial role for the overall efficiency of such. In this regard, heat flows resulting from PtH2 may lead to synergies with the heat supply of DH systems. This paper discusses the potentials of PtH2 as a relevant heat source for DH (with focus on Austrian system conditions). Technology-specific efficiencies, heat flows and temper-atures are put in context with today's and future DH system specifications and synergies are analyzed. A qualitative analysis summarizes the opportunities and challenges that arise from a system perspective, e.g. electrolyzer location, user type, and user-specific operation (i.e. generation load). It is found that high-temperature electrolysis is likely to be fully integrated in industrial utility operations and heat utilization corresponds to the well-known challenges of inte-grating industrial waste heat into DH networks. The location of low-temperature elec-trolysis is subject to infrastructure limitations and the economics of utilizing by-products. Operation is likely to be more electricity-market-oriented and may seasonally differ from heat demand. However, its waste heat is sufficient to feed modern low-temperature DH networks and by 2030 could cover up to 12% of Austria's current DH demands and up to 4% of the EU demand for heat below 100 degrees C. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.