What are the causes of T5 at solar engine turbine?

T5 in a solar engine turbine typically refers to a temperature measurement at the turbine's inlet or outlet. Causes of elevated T5 can include insufficient cooling of the working fluid, excessive heat absorption from the solar collector, or inefficiencies in the turbine's thermodynamic cycle. Other factors may include mechanical issues or design limitations that prevent optimal heat transfer, leading to increased thermal stress and potential performance degradation.