IEA DHC Annex XIV project 06: HY2HEAT Using electrolysis waste heat in district heating networks

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. Approximately one third of the electricity used to generate the hydrogen will be wasted as heat. This may translate into a future waste heat amount of 4000 TWh (800 GWth at 5000 full-load hours) globally until 2050; compared to 3200 TWh global district heating (DH) demand in 2014. A potential that must be considered as a heat source for DH networks.

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 DH purpose.

The aim of HY2HEAT is

1. to analyse the techno-economic synergies of electrolysis waste heat integration in DH systems (including the assessment of the role and expected volumes),
2. to evaluate the best technical solutions for capturing and upgrading the electrolyser waste heat for utilisation in DH networks, and
3. to derive a practical guide for DH operators for the pursuit of the potential and its technical integration.

Objectives

• Estimating expected electrolysis capacity in all IEA-DHC member countries, with more detailed analyses of Austria, Norway, Estonia (project partner countries).
• Quantification of congruence & mismatch of electrolysis waste heat supply and DH demand, regarding electrolyser technology, time, site, and technical requirements.
• Elaborating three concrete use cases and their technical design, techno-economic benefits, and business/collaboration model.
• Finding best practices for the technical integration: evaluating optimal approaches for capturing heat at highest possible temperature together with electrolyser suppliers, and deriving optimal combinations of heat upgrade technologies and thermal storage systems; .
• Performing techno-economic assessment of hydrogen costs alone, and hydrogen and heat costs in a coupled production from the perspective of electrolysis operators (i.e., demonstrate the benefit offered by DH integration) and DH operators.
• Conducting a survey of current perception: perspective of DH operators and expected electrolysis operators on perceived relevance of future collaboration, expected barriers, and competitiveness with other heat sources.

Austria (lead), Norway, Estonia

Project lead

Dr. Simon Moser
Energieinstitut an der Johannes Kepler Universität Linz (EI-JKU)
Altenberger Straße 69, 4040 Linz
Email: moser@energieinstitut-linz.at

Project partner