Subtask A: Development and Characterization of Improved Materials

The goals in this Subtask are to develop and characterise storage materials in order to improve the TES system performance, and to identify and measure material properties. The material database started in Task42/Annex 24 and Task42/Annex29, shall be maintained and expanded.

The subtask is subdivided into “Phase Change Materials” and “Thermochemical Materials”, since technical details are completely different.  

Subtask B: Measuring Procedures and testing under Application Conditions

In this Subtask measuring procedures for relevant material properties shall be defined. The list of material property measurements, which need these common procedures, differs for PCM and TCM.

For PCM the focus will be on up scaling effects (going from ml range to litre and even larger quantities), which influence melting behaviour, enthalpy and supercooling effects. For thermochemical materials to identify a common procedure to measure the reaction enthalpy will be most important.

Operation conditions of relevant applications which are to be identified in Subtask 4 shall be used for realistic performance testing. Storage capacity as well as the stability after a number of storage cycles will be the main parameters to be identified. Also corrosion in conjunction with the storage material will be investigated. 

The subtask will be subdivided in a subtask “Procedures for Phase Change Materials Testing” and “Procedures for Thermochemical Materials Testing”, since the technical details are completely different.

Subtask C: Component design for innovative TES materials

A new focus of the joint Task/Annex will be 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 most important for any economic analysis of the storage system.

The subtask will be subdivided in the subtasks “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 up to now, there is no common procedure proposed to assess the performance of the components in order to compare them. This new joint Task/Annex aims to contribute to this common assessment procedure.

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

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

This subtask shall collect parameter sets for operation conditions of relevant fields of application. The data shall be found within the activities of other Annexes and TCPs.

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