# Companion files — Data Center Design, Resilience, Reliability and Sustainability (version 1.1, October 24, 2026)

George, C. B. (2026). *Data Center Design, Resilience, Reliability and Sustainability: Power, Cooling, Redundancy and Cost for 100–300 MW Campuses, with a Virginia Reference Design Applied Nationwide and Globally.* Sanctir working paper, version 1.1, October 24, 2026. License CC BY-NC-ND 4.0. ORCID 0009-0007-8162-6839.

These files reproduce every figure in Section 12 (delivered cost) and the climate tables in Sections 6, 16.1 and 17.3. They are published under the same CC BY-NC-ND 4.0 license as the paper.

| File | What it is | How to use it |
| --- | --- | --- |
| `Data_Center_Cost_Model_v2.1_2026-10-24.xlsx` | Cost model, version 2.1. Sheets: README, Inputs (every assumption in a labeled blue cell), Tariff (every Dominion Energy Virginia component as published, summed by formula into the bill), Model (three arrangements × three cases, totals, $/MWh, decomposition), Design conditions (41 stations). 157 formulas; recalculates without errors in LibreOffice and Excel. | Change any blue input and recalculate. The Model sheet reproduces the paper's Section 12 figures. |
| `model_v2.py` | Python script that computes the same results as the workbook (no dependencies beyond the standard library). | `python3 model_v2.py tariff_2026-10-24.json` prints the three cases and the bill. |
| `tariff_2026-10-24.json` | Tariff input file: each Dominion component with its rate, unit, effective date and source sheet, plus the modeling notes. | Input to `model_v2.py`; edit to test another tariff. |
| `design_conditions_tmyx_2011-2025.csv` | 41 stations: annual 0.4%, 1% and 2% cooling design dry-bulb, mean coincident wet-bulb, typical-year maximum, and hours above 27, 30, 32, 34, 36, 38 and 40 °C. | Source table for Sections 6, 16.1 and 17.3 and the workbook's Design conditions sheet. |
| `station_manifest.csv` | For each station: WMO number, TMYx 2011–2025 file stem, directory on climate.onebuilding.org, the design-condition data-source line read from the .ddy header ("2025 ASHRAE Handbook -- Fundamentals - Chapter 14 Climatic Design Information" for all 41), and the 0.4% values. | Provenance record; input to `count_hours.py`. |
| `count_hours.py` | Downloads each station's TMYx zip from climate.onebuilding.org, reads the design conditions from the .ddy member and counts the hourly dry-bulb exceedances from the .epw member. | `python3 count_hours.py station_manifest.csv` writes `design_conditions_reproduced.csv`. Needs network access; standard library only. |

Status date of the tariff inputs: October 24, 2026 (Schedule GS-4 effective January 1, 2026; Rider A effective July 1, 2026; riders as in the Exhibit of Applicable Riders effective September 1, 2026). Schedule GS-5 unit rates were not yet filed; GS-4 transmission-voltage rates are the proxy, with the GS-5 minimum-billing provisions applied. Equipment costs, the firm gas transportation rate and the gas lateral are engineering estimates, as stated in the paper's Section 15.

Version history: v2 (October 23, 2026) rebuilt the model on a common reliability baseline with the tariff-based bill; v2.1 (October 24, 2026) added the Schedule GS-4 off-peak generation demand charge and Section IX billing-period proration, repriced battery charging losses as energy drawn above energy delivered, and reserved firm gas for arrangement E at the campus peak (Appendix B, item 5 of the paper).