Description

1. Addresses Project Cape Construction Timelines & Reservoir Engineering Updates NREL/GEOPHIRES-X#443
2. Addresses Remove or clarify SAM-EM project payback period NREL/GEOPHIRES-X#413 (8764602)

Web interface links:

1. Fervo_Project_Cape-5 (Phase II): https://gtp.scientificwebservices.com/geophires/?shared-geophires-result-id=891748dd-932b-4b04-9f70-5a1f0deaea63
2. Fervo_Project_Cape-6 (Phase I): https://gtp.scientificwebservices.com/geophires/?shared-geophires-result-id=0b78909a-abcb-4187-9318-90cf72d5a6fd

TODO

1. 🚧 SME review (reservoir engineering)
2. 🚧 Incorporate ATB updates: https://atb.nrel.gov/electricity/2024b/geothermal
3. Sensitivity analysis: address why higher flow rates != better economics
4. Reference https://www.resfrac.com/wp-content/uploads/2025/06/Singh-2025-Fervo-Project-Cape.pdf: 0b7da6c
5. Calibrate exploration cost to https://atb.nrel.gov/electricity/2024b/geothermal: b94b01f
   1. Created tracking issue to update GEOPHIRES correlation :Update exploration cost correlation according to 2024b ATB NREL/GEOPHIRES-X#447
6. 🚧 Documentation and references
   1. 🚧 Clarify calibration of drawdown/redrilling wrt 1-2% expected annual decline
   2. Construction CAPEX schedule
   3. Approach & Methodology update: Clarify SOAK vs. FOAK vs. NOAK: 1e960e4
   4. Describe case study use cases e.g. as a template for custom modeling: 1e960e4
   5. ITC
   6. TOD/ambient temp: 3f96592
   7. OCC vs total capex: a791d54
7. Sensitivity analysis chart tweaks:
   1. Flow rate text overlap
   2. Link titles (on hover)
8. Sensitivity analysis: https://github.com/scientific-web-services/geophires-fpc4-sensitivity-analysis
9. Surface temperature fine-tune based on Project InnerSpace GeoMap: 9af9f1d
10. Multiple construction years: Update Fervo_Project_Cape-4 based on publicly stated timelines - https://fervoenergy.com/fervo-energy-raises-462-million-series-e-to-accelerate-geothermal-development-and-meet-surging-energy-demand-with-clean-firm-power/
    1. Phase II: 500 MW: Fervo_Project_Cape-4
    2. Phase I: 100 MW: Fervo_Project_Cape-5: 71607b7
11. Reservoir engineering updates
    1. ~8.5" ID
    2. Flow rate
    3. Fracture surface area
    4. PI/II instead of impedance
    5. Number of Fractures per Stimulated Well
    6. Increased lateral length (adjust fracture separation accordingly)
12. Higher discount & bond rates

Testing & Verification

1. Unit tests added: Retains test for previous version: https://github.com/softwareengineerprogrammer/GEOPHIRES/pull/117/changes#diff-77443b51920606ff05244e83370cb4bbd78fb8ee13076d9356d5051c2c9fbef5
2. Unit tests updated: https://github.com/softwareengineerprogrammer/GEOPHIRES/pull/117/changes#diff-35ea0c0b80463f35958a7d1d7396bad7ad397a7c8e8d96a49da5b90e756c7c7c
3. Manually tested

Change Checklist:

Observe the following checklist items if your change includes a new version (see versioning notes and version management docs).

Before merging:

1. Add a CHANGELOG entry (example). RST Template:

M.m.P: `TITLE <https://github.com/NREL/GEOPHIRES-X/pull/PR-NUMBER>`__ | `release <https://github.com/NREL/GEOPHIRES-X/releases/tag/vM.m.P>`__

After merging:

1. Push tag(s) to GitHub: git push origin refs/tags/vM.m.P
2. Post a change announcement to the GEOPHIRES Change Announcements Discussion (example). Markdown template:

M.m.p: [TITLE](https://github.com/NREL/GEOPHIRES-X/pull/PR-NUMBER) | [release](https://github.com/NREL/GEOPHIRES-X/releases/tag/vM.m.P)