Subtask A: Development and Characterization of Improved Materials

The goals of this Subtask were to develop and characterize storage materials to improve the TES system performance and to identify and measure material properties. The material database started in SHC Task 42/ES Annex 24 and SHC Task 42/ES Annex 29 was expanded.

The Subtask was subdivided into “Phase Change Materials” and “Thermochemical Materials” due to their completely different technical details.  

Subtask B: Measuring Procedures and testing under Application Conditions

In this Subtask, measuring procedures for relevant material properties were defined. The material property measurements needing these common procedures differ for PCM and TCM.

For PCM, the focus was on upscaling effects (going from ml range to liter and even larger quantities), which influence melting behavior, enthalpy, and supercooling effects. For thermochemical materials, the focus was on identifying a common procedure to measure the reaction enthalpy.

Operation conditions of relevant applications identified in Subtask D were used for realistic performance testing. Storage capacity and stability after a number of storage cycles were the main parameters identified. Also, corrosion in conjunction with the storage material was investigated. 

The Subtask was subdivided into “Procedures for Phase Change Materials Testing” and “Procedures for Thermochemical Materials Testing” as the technical details are entirely different.

Subtask C: Component design for innovative TES materials

A new focus for this joint Task was on component development for newly developed materials. The improved performance of thermal storage systems – system energy density, output temperature, thermal power, storage efficiency, stability, and others -  with a new material strongly depends on heat (and mass) transfer of heat exchangers, reactors, evaporators, and condensers. The design of the component is also important for any economic analysis of the storage system.

The Subtask was subdivided into “Component Design for Phase Change Materials” and “Component Design for Thermochemical Materials” since the technical details are completely different.

There are different approaches (concepts) to improve the performance of the storage components. But until now, there is no common procedure proposed to assess the performance of the components to compare them. This joint Task contributed to this common assessment procedure.

Subtask D: Energy Relevant Applications for an application-oriented Development of improved Storage Materials

The overall goal of the Task was to develop improved thermal energy storage materials (and reactions) for better performance. Since energy storage systems, in general, are strongly linked to the operation conditions of their actual application, it is crucial to define these conditions carefully. The potential improvement of any new material development should be evaluated as soon as possible under such conditions to give a first hint of the improved performance within its application configuration.

This Subtask collected parameter sets for operating conditions in relevant fields of application. 

The work is not divided into PCM and TCM-related applications.