Operational experiences with the heliostat field at the Juelich solar towers

Kurzfassung

The heliostat field at the Juelich solar towers meanwhile has a history of 15 years of operation experience. This paper gives a short overview over the problems and improvements since the first erection of the field. Reflectors had to be replaced after just 5 years of operation and have been refitted with a high quality four facet reflector system with individual canting. Results of deflectometric measurements will be demonstrated. The poor tracking performance of the initial heliostat design led to a retrofit of the tracking system in the years 2019 to 2023. With the current system precise tracking could be achieved since mid-2021. This paper will show different technological approaches to reach the desired quality improvements. Tracking results from the first days of operation to the current day will be presented. The whole field is operated by the heliostat field control system HeliOS. The control system has some specific functionalities which are uncommon to standard single tower systems but are a requirement for the research focused field in Juelich and for the simultaneous operation of multiple receivers in two adjacent towers by multiple operators. We will demonstrate some features of the system in this paper.