FPC5 discussion section

docs/Fervo_Project_Cape-5.md.jinja

@@ -476,6 +476,37 @@ Key differences:
 
 {# TODO others e.g. Fervo_Project_Cape-3... #}
 
+## Discussion, Limitations, & Future Work
+
+While this case study establishes a validated economic baseline for Second-of-a-Kind (SOAK) EGS using standardized
+consensus data, users should interpret results (LCOE, IRR, NPV, etc.) as an assessment of intrinsic project
+viability rather than a fully burdened commercial pro-forma.
+Several financial, technical, and operational factors were not explicitly modeled and represent areas for future refinement.
+
+Users may wish to explicitly encode these cost factors in their own models by using applicable adjustment parameters.
+For OPEX, such parameters may include `Wellfield O&M Cost Adjustment Factor`,
+`Surface Plant O&M Cost Adjustment Factor` or `Total O&M Cost`.  For CAPEX, `One-time Flat License Fees Etc` or
+`Total Capital Cost` may be appropriate.
+
+### Financial Considerations
+
+The case study economic results focus on project-level cash flows but do not explicitly itemize several overhead costs
+and administrative realities often associated with commercial project financing.
+Including these may reduce the levered IRR.
+
+1. Transaction & Closing Fees: The Total CAPEX includes interest during construction but does not explicitly budget for debt closing or bank fees. In large-scale energy infrastructure, these transaction costs may constitute a small percent of total debt volume. [Click here](https://github.com/NatLabRockies/GEOPHIRES-X/issues/451) to view the relevant GEOPHIRES tracking issue on GitHub.
+1. Reserve Accounts: The cash flow analysis assumes immediate liquidity. It does not model working capital, debt service, or major equipment replacement reserve accounts. Project financial partners may require that the project owner(s) establish and fund reserve accounts. [Click here](https://github.com/NatLabRockies/GEOPHIRES-X/issues/460) to view the relevant GEOPHIRES tracking issue on GitHub.
+1. Insurance Premiums: The model does not include a specific line item for insurance. For EGS projects involving deep subsurface risks, insurance premiums could represent an additional annual operating expense. [Click here](https://github.com/NatLabRockies/GEOPHIRES-X/issues/369) to view the relevant GEOPHIRES tracking issue on GitHub.
+
+### Technical & Operational Considerations
+
+1. Grid Interconnection & Transmission: For a 500 MWe project, interconnection costs (substation upgrades, gen-tie lines) can be substantial. Unless the site is adjacent to high-capacity transmission with available queue space, interconnection costs could add materially to the project budget.
+1. Seasonal and Hourly Performance Granularity: As noted in the Surface Plant Parameters, this study uses a fixed annual average ambient temperature. It does not model the seasonal or hourly impacts on air-cooled condenser efficiency. In reality, power output would likely dip during peak summer hours and increase during winter. Future versions of GEOPHIRES may add support for these considerations; [click here](https://github.com/NatLabRockies/GEOPHIRES-X/issues/395) to view the relevant GEOPHIRES tracking issue on GitHub.
+1. Redrilling Assumptions: Management of thermal decline is modeled as periodic redrilling events that reset the reservoir's heat content to initial conditions at intervals determined by the `Maximum Drawdown` parameter. The cost of these events is amortized into a uniform annual operating expense. In reality, these events may be scheduled as discrete capital-intensive campaigns punctuated by years of lower spending, or as a continuous program of make-up well drilling to mitigate decline. [Click here](https://github.com/NatLabRockies/GEOPHIRES-X/issues/381) to view the relevant GEOPHIRES tracking issue on GitHub.
+1. Reservoir Modeling Fidelity: The base case utilizes the Gringarten analytical model, which produces a characteristic thermal plateau maintained until a sharp breakthrough event. A key open question is whether this idealized profile provides an acceptably accurate approximation of drawdown over time, or if it masks the gradual dispersion caused by flow channeling and heterogeneity. Future work should evaluate whether Gringarten remains the optimal scoping proxy, or if an alternative analytical solution[^alt-analytical-solution-proposal] would offer a superior balance of speed and realism by better mimicking the shape of numerical simulation outputs.
+
+[^alt-analytical-solution-proposal]: Possible alternatives might include Residence Time Distribution (RTD) modeling, or a parameterized profile generator based on the Bezier curve approach used in the "ResFrac Profile" variant.
+
 ---
 
 ## References

src/geophires_x/Economics.py

@@ -920,7 +920,8 @@ def __init__(self, model: Model):
             Valid=False,
             ErrMessage="calculate total capital cost using user-provided costs or" +
                        " built-in correlations for each category.",
-            ToolTipText="Total initial capital cost."
+            ToolTipText=f'Total initial capital cost. For SAM Economic Models, '
+                        f'this is treated as the {overnight_capital_cost_output_parameter().Name}.'
         )
         self.oamtotalfixed = self.ParameterDict[self.oamtotalfixed.Name] = floatParameter(
             "Total O&M Cost",

src/geophires_x_schema_generator/geophires-request.json

@@ -1639,7 +1639,7 @@
       "maximum": 10
     },
     "Total Capital Cost": {
-      "description": "Total initial capital cost.",
+      "description": "Total initial capital cost. For SAM Economic Models, this is treated as the Overnight Capital Cost.",
       "type": "number",
       "units": "MUSD",
       "category": "Economics",