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Plant developers of parabolic trough collector (PTC) systems for industrial steam generation face various challenges. Some of the main challenges are availability of land, buildings in the vicinity of the plant that cast shadows on the collectors as well as land restrictions. The typical north-south collector axis alignment in many cases may not be possible due to limits of available ground. These were challenges that were faced in the planning phase for installing a PTC plant on the premises of the KEAN Soft Drinks Ltd factory in Limassol, Cyprus. As these issues cannot be avoided they must be accounted for by the plant developer, especially when a performance guarantee is given. This work presents, amongst other things, factors that should be analysed in order to predict the energy yield in the planning phase as best as possible by using a simulation model. In the sensitivity study presented in this paper, several effects on the energy yield were investigated theoretically. These effects include: Tracking inaccuracy, non-parallel collector row axis orientations as well as north-south vs. east-west collector alignment. A dynamic simulation model developed by the Solar-Institut Jülich (SIJ) [1] was further developed and used for the analysis. The simulation model features a deviation between the measured and simulated oil temperature at the collector outlet of only 1.5 K (rms). The findings are presented in this paper and give an insight into the effectiveness of mid-sized PTC systems for the industry sector. [ABSTRACT FROM AUTHOR]

Parabolic trough collector (PTC) systems are commercially available concentrating solar power plants widely known for their application to generate electrical power. To further reduce the dependency on fossil fuels, such systems can also be deployed for producing process heat for industrial purposes. In combination with a thermal energy storage system, this technology has the ability to reliably supply on-demand process heat. This paper gives details on a fully automated PTC system with concrete thermal energy storage (C-TES) and kettle-type boiler that supplies saturated steam for a beverage factory in Limassol, Cyprus. In the focus is the validation of a dynamic simulation model in Modelica® that physically describes the entire PTC system. The simulation model uses various plant data as inputs including mirror reflectivity and weather data from on-site measurements. The validation was carried out in three steps. First, the PTC was validated as a stand-alone component. A time-dependent inlet oil temperature vector was given as input and the outlet oil temperature was computed. The root mean square (rms) error between the measured to simulated outlet oil temperature values results in 3.86% (equivalent to about 1.9 K). The second part of the validation then considered a complete PTC oil cycle in PTC-and-boiler operation mode (without C-TES). In the simulation, both the PTC inlet and outlet oil temperatures were computed. The result is a deviation < 4.25 % (rms) between measured to simulated values. Finally, in the third step, the C-TES model was validated as a stand-alone component. The deviation between measurement and simulated values is < 5% compared to the design point. [ABSTRACT FROM AUTHOR]