Optimization potential also exists with regard to the heat fluid cycle. At the moment a synthetic fluid circulates in the absorber pipes. Flagsol is currently researching the use of molten salt, which until now is only being used for the storage tanks, in the heat transfer system as well. The molten salt can be heated to higher temperatures than the heat transfer medium used today, resulting in higher overall efficiency of the system. Furthermore, this would save heat transfer fluid in the collector cycle and skip heat exchanger step when loading the storage tanks.