Demonstration project on direct steam generation technology successfully concluded

When the test plant located in Carboneras, Spain was dismantled in the beginning of 2012, the research project ’Real-Diss’ promoted by the Federal Environment Ministry had already proven to be a big success. The objective of the project was the development and qualification of critical components for the direct steam generation technology (DSG) in co-operation with the highly qualified project partners Schott, Senior Berghöfer, DLR, and Endesa. For this purpose, a test plant had been built and operated at the power plant area of Endesa. The plant comprised a 24m SKAL-ET collector, a concrete-type thermal storage (250 kWh, maximum 400°C) and a phase change thermal storage (PCM, 720 kWh at 306°C) for the condensation of the steam and the conversion of the water into steam, respectively. For testing purposes, the power plant made overheated steam of almost 500°C available.

All tests were conducted successfully. For the very first time ever it was possible to show that the components were capable of resisting extreme conditions of 500°C and of more than 120 bar and that the storage system of this size worked in various modes of operation. In this context, charging took place at approximately 112 bar/320 °C and discharging at approximately 78 bar/293°C.

By participating in the project, TSK Flagsol further enhanced its competence in the field of direct steam generation technology. Even if present evaluations indicate that the relevance of DSG for solar-thermal power generation is not as high as originally expected, it has to be pointed out that the knowledge gained in the project is highly relevant for promising markets like enhanced oil recovery (EOR) or steam augmentation.