A techno-economic analysis of implementing temperature-maintaining modifications on the steam turbine of a solar thermal power plant

Abstract: This master thesis examines the techno-economic implications of introducing temperature maintaining modifications on the steam turbine in a direct steam generation solar tower power plant. More specifically, the impact on the maintenance requirements and other performance indicators when installing electrical heat blankets as well as increasing the gland steam temperature, was examined. A model of the Ivanpah plant in southern California was inherited and further developed within the KTH in-house tool DYESOPT to then be used for sensitivity studies focusing on examining the effect of the start improvements.The results show that with the assumptions made, the examined start improvements can be used to significantly increase the power output of the Ivanpah plant while at the same time reducing the maintenance requirements. The investment costs of said improvements were also found to be low in relation to their techno-economic benefits, resulting in a significant reduction of the levelized cost of electricity. The conducted sensitivity studies also suggested that the assumption made were not very sensitive, although more accurate assumptions regarding the costs of the turbine start improvements should be looked at during further development.