igure 4. Variation of DNI Figure 5. Solar Field output
As shown in Fig. 6(a), the additional steam mass flow generated by HSSG
varies as it depends on solar radiation to reach a maximum of 65 kg/s
when DNI gets at maximum. As a result, the total SPT output (Fig. 6(b))
is equal to 62 MW compared to that at night equal to 35 MW, which means
an increase in electricity production about 27 MW. Fig. 6(c) gives an
idea about the power plant output during the 21st of
March (design point) at the specified site conditions. During the nights
or cloudy periods ISCC operates as CC and produces about 129 MW and its
thermal efficiency reaches 52 %, according to Fig. 6(d), while during
the day, the net electricity production is increased to 156 MW and the
thermal efficiency reach its highest value of 63 % at midday. The
estimated solar electricity ratio ( Fig. 6(e)) based on
the difference in electrical output of ISSC mode and CC mode varies from
sunrise to sunset according with solar radiation to reach a maximum of
17 % at midday.