Survey Highlights Key Trends and Challenges in Thermal Energy Storage

As part of the TREASURE project, a recent expert survey led by Hamburg Institut gathered valuable insights from PTES initiatives in Denmark, France, Austria, Croatia, and China. The survey aimed to support the development of a practical Implementation Guideline for Large-Scale Thermal Energy Storage (LTES) on the City Level, a key TREASURE deliverable that will help municipalities and urban planners deploy PTES more effectively.

The results reveal strong consensus on several technical aspects: surveyed projects consistently used PTES to store seasonal surplus heat and reduce peak winter demand, often in combination with heat pumps for post-heating. Yet, while the technology shows significant promise, the survey also identified persistent implementation challenges, particularly around financing models and permitting processes. Some projects relied on private equity, while others were highly dependent on public subsidies. Delays in planning and tendering procedures were frequently reported, even in technically advanced regions.

These findings will directly inform the forthcoming guideline, offering evidence-based recommendations for local authorities, utilities, and energy experts seeking to incorporate PTES into sustainable district heating networks.