Hydrogen will play a central role in a future climate-neutral energy system. It will primarily be produced by electrolysis, and significant production capacities are planned on a global scale. Hydrogen can be used directly to cover peak load demands and/or in combined heat and power (CHP) plants, including fuel cells, to generate electricity. However, these are evident applications of hydrogen and are therefore out of scope of this project. HY2HEAT focuses on the waste heat utilisation from electrolysers for district heating purpose, which is around one third of the electricity used to generate the hydrogen. The aim of HY2HEAT is to analyse the techno-economic synergies of electrolysis waste heat integration in district heating systems (including the assessment of the role and expected volumes), to evaluate the best technical solutions for capturing and upgrading the electrolyser waste heat for utilisation in district heating networks, and to derive a practical guide for district heating operators for the pursuit of the potential and its technical integration.