Don't subtract ITC from capex for SAM Economic Models (as opposed to previous behavior which subtracted and then re-added later)

Author: softwareengineerprogrammer

src/geophires_x/Economics.py

@@ -3081,8 +3081,9 @@ def calculate_total_capital_costs(self, model):
         else:
             self.CCap.value = self.totalcapcost.value
 
-        # update the capital costs, assuming the entire ITC is used to reduce the capital costs
-        if self.RITC.Provided:
+        if self.RITC.Provided and self.econmodel.value != EconomicModel.SAM_SINGLE_OWNER_PPA:
+            # update the capital costs, assuming the entire ITC is used to reduce the capital costs
+            # (not applied for SAM Economic Models since they handle ITC in cash flow, not capex)
             self.RITCValue.value = self.RITC.value * self.CCap.value
             self.CCap.value = self.CCap.value - self.RITCValue.value
 

src/geophires_x/EconomicsSam.py

@@ -346,8 +346,7 @@ def _get_single_owner_parameters(model: Model) -> dict[str, Any]:
     # calling with PySAM. But, we set it here anyway for the sake of technical compliance.
     ret['flip_target_year'] = model.surfaceplant.plant_lifetime.value
 
-    itc = econ.RITCValue.quantity()
-    total_capex = econ.CCap.quantity() + itc
+    total_capex = econ.CCap.quantity()
 
     if econ.inflrateconstruction.Provided:
         inflation_during_construction_factor = 1.0 + econ.inflrateconstruction.quantity().to('dimensionless').magnitude