*2.1. Solar Field*

The solar field comprises parallel rows of solar collector arrays and typical glass mirrors of 61 MW installed thermal capacity. The solar field comprises 40 loops, each loop having four parabolic trough collectors (type Skal-ET 150 designed by TSK Flagsol Engineering GmbH), and each collector has an aperture area of 817.15 m2.

The solar heat transfer from the solar field collectors (PTCs) to the steam cycle uses a heat transfer fluid (HTF) system. The HTF is Therminol VP-1 from Solutia (ultra-high-temperature, liquid/vapor phase fluid) and operates between 12 ◦C and 400 ◦C (54–750◦F) [20,21]. The HTF system is designed for an HTF mass flow of 250 kg/s at full load (61 MW of solar field thermal power output). Hot HTF returning from the solar field at 393 ◦C is pumped through the solar heat exchanger. The HTF leaves the solar heat exchanger at 293 ◦C and is pumped back into the solar field, as shown in Table 1.


**Table 1.** The solar field design parameters [15,16,22].
