ESPERANZA II: crew-time-constrained bioregenerative food system for a 500-sol Mars surface mission — preprint v1, 14-sol meal plan workbooks and reconciliation scripts

ESPERANZA II is a bioregenerative food system designed for a crew of fifteen over a 500-sol Mars surface rotation, developed as a solo entry for the 2026 NASA Mars to Table Challenge (submitted 11 August 2026; not selected as finalist). This record contains the preprint, the 14-sol meal-plan workbooks exactly as submitted, and the scripts that recompute every figure in the paper from those workbooks. WHAT IS DIFFERENT ABOUT IT The challenge rules left mass, power, volume and water unconstrained and bounded one thing: crew time (45 hours per five sols for each of two food specialists). ESPERANZA II is therefore sized against labour, not against mass or power. Every resource budget (lighting, water, heat rejection, CO2, O2, hours) is closed against its neighbours rather than estimated independently; that coupling exposed and corrected a five-fold error in an earlier transpiration estimate. KEY FIGURES (all reproducible from the included files) · 511 m² of production: 373 m² LED sole-source crop canopy, 40 m² cyanobacterial photobioreactor, 48 m² Tenebrio molitor rearing, 50 m² fungal culture · 58.1 kW mean electrical demand (64.0 kW peak); canopy lighting 30.4 kW mean, peak held within 9 % by photoperiod tessellation · 644 L per sol canopy transpiration, recovered at 98.5 % · 20.7 kg CO2 per sol fixed; oxygen release 116 % of crew demand · 78 distinct meals per 14-sol rotation, 3,060 kcal per crewmember per sol · 1,004 ingredient operations recomputed: 15.40 h of galley labour per sol; the two specialists peak at 79.5–81.2 h of their 90 h budget · Earth-provisioned energy 41.2 % (per-ingredient audit) / 47.0 % (crop-nameplate basis), below the 50 % cap · Technology readiness from TRL 3 (regolith mineral classification) to TRL 6–7 (LED crops, fermentation) LIMITATIONS ARE STATED, NOT HIDDEN No dynamic crop-growth simulation; task durations are engineering estimates, not measured in an analogue galley; the iron content of the rotation exceeds the spaceflight ceiling and is declared as an open non-conformance; no cost analysis. The full list is in section 6 of the paper. FILES Preprint v1 (18 pp.) · 2.1 meal schedule and 2.2 meal lifecycle workbooks (as submitted) · 01_recompute_from_deliverables.py, 02_figures.py, results.json, per_sol.csv · paper figures · submitted Solution Summary, Concept of Operations with appendix, and Design Layout. Documents and data CC BY 4.0; scripts MIT. Code mirror: https://github.com/engimine/ESPERANZA_II OPEN TO COLLABORATION The author is a mining engineer (Spain), international winner of NASA's LunaRecycle Challenge 2025 (Digital Twin category), working independently on regolith-to-table systems for the Moon and Mars. If your programme, laboratory, university or company works on closed-loop life support, habitat operations, controlled-environment agriculture, space food, ISRU or analogue campaigns and you think this work could help yours (design reconciliation, crew-time accounting, meal-plan lifecycle modelling, regolith processing), write to me. I answer personally. Contact: [email protected] · https://www.mariajesuspuertaangulo.com · https://esperanzaresearch.com