The present study is in line with the work of Li et al. [28], Xu
et al. [29] and Ronan et al. [30]. Li et al. [28] modeled a cavity receiver
of a solar tower power plant using molten salts as a heat
transfer fluid; taking into account all thermal losses from the receiver.
Considering the same power plant design, Xu et al. [29] have
developed an energy and exergy analysis for the main subsystems
of power plant. They evaluated the effect of the DNI and of the concentration
ratio on the energy and exergy efficiencies, and the effect
of the concentration ratio on the receiver surface
temperature and on the receiver aperture area. Ronan et al. [30]
have developed a mathematical model to assess the influence of
key system temperatures, thermal conductances and the receiver
irradiance on the optimal receiver temperature and solar-to-electric_efficiency
of solar-trough and solar-tower power plants. Using
molten salts as a working fluid, they have found that the optimal
level of receiver irradiance occurs at about 200 kW/m2 for solar
tower and solar trough systems. So, the optimal estimated receiver
temperatures suggest the use of sub-critical Rankine cycles for solar
trough plants, but super-critical Rankine cycles for solar tower
plants.