I modelled a Solar Tower with 50 MW and design features as suggested by the optimization wizard and the different cost from published papers. I got 2 different results with fired PPA and with fixed IRR. However when I check the 2 options of allowing SAM to pick a debt fraction and also to pick PPA escalation rate I get LCOE real of 4.5 UScents/kwh which obviously does not look realistic. How could I understand this problem.?
