(a) (b)
Figure 8. Performance of ISCC during nights and cloudy days: a) Power; b) Efficiency
Table 14 compares between the three power plants in terms of LCOE, fuel saving and emission, considering CC as the reference power plant. Fig. 9 and Fig.10 show the calculated LCOE subdivided into three parts: investment cost, O&M cost and fuel cost. LCOE is greatly affected by the specific cost of power plant, especially the solar parts, since their costs are very high compared to the fossil parts. According to Fig. 9 when the environmental cost is not taken into consideration, CC power plant has the lowest LCOE followed by GT. In the case of ISCC, LCOE has a value higher by 3 % compared with GT and 28 % higher than CC. If one considers the environmental effects as shown by Fig. 10, LCOE of ISCC becomes 0.0272 $/kWh which is about 6 % lower than for GT and 20 % higher than CC, but LCOE of CC is still the lowest.
Fig. 11 and Fig. 12 show the specific fuel consumption (kg/MWh) and CO2 emission (kg/MWh). ISCC has the lowest specific fuel consumption about 7 % which is lower than that of CC and 32 % lower than GT. As a consequence, ISCC allows saving about 18.45 million $ of fuel consumption through 30 years of its operation. Fig. 12 permits concluding that CO2 emission is proportional to the fuel consumed, which is extremely high in TG but lesser in CC power plant. Due to availability of the solar energy during the day, ISCC has the lowest CO2 emission, thus avoiding 0.89 million ton of CO2 emission over 30 years of its operational period.
Table 14. Estimated LCOE