The Trust Collective

The Numbers

Sector-by-sector analysis with peer-reviewed citations and honest gaps

All figures are first-order estimates. Peer review invited. The direction of honest correction is always toward longer timescales and greater complexity. These are the most honest numbers we have. All quantitative claims are supported by peer-reviewed citations catalogued in Citation Appendix V2.

PART ONE: ENERGY

Total Demand

TC sustained demand: ~25 TW. Peak demand during construction era (years 0–200): ~30–35 TW. Derived from bottom-up sectoral analysis. Current global primary energy is ~18 TW (IEA 2025), but ~60–65% is wasted as heat in fossil combustion. An all-electric TC civilization serves the same useful work far more efficiently.

### Energy Budget by Sector

| --- | --- | --- | --- |

| Residential & commercial | 2.5–3 | 2.5–3 | Earth-sheltered cities slash heating/cooling 50–70% |

| Underground food production | 2–6 | 2–6 | LED lighting dominant load; varies with floor area |

| Transport (robo taxi + freight) | 1.5–2 | 1.5–2 | 80% fewer vehicles, all-electric, 85–95% motor efficiency |

| Manufacturing & industry | 3–5 | 8–10 | Peak during pyramid city and tunnel construction |

| Water (desalination + cleanup) | 0.5–1 | 0.5–1 | Desalination for coastal/arid only; rainwater primary inland |

| Direct Air Capture | 0.2 | 0.2 | 1 GtCO₂/yr at 5–8 GJ/tonne |

| Restoration robotics | 1–2 | 1–2 | Solar-powered autonomous systems over tens of millions km² |

| AI governance & computation | 0.5–2 | 0.5–2 | Civilization-scale resource management and Dr. Bot |

| Space operations | 0.2–0.5 | 0.2–0.5 | Spaceline, L1 manufacturing, biomethane launches |

| Overhead (transmission, storage) | 3–5 | 4–6 | ~20% for grid losses, storage cycling, redundancy |

| TOTAL | ~20–27 | ~28–35 | |

The TC civilization requires roughly one-seventh the energy per unit of useful work compared to current fossil-based systems. Energy supply is not the constraint — geothermal alone provides ~50 TW at moderate depths (IEA 2024), with hundreds of TW accessible at greater depths. Even at peak construction demand, the TC uses less than 70% of accessible geothermal capacity before adding any supplemental sources.

Primary Source: Geothermal

Accessible geothermal (advanced drilling): ~50 TW baseline, expandable. IEA (2024) The Future of Geothermal Energy found 42 TW EGS potential at <5 km depth, ~600 TW at <8 km. CATF (2024) found 1% of superhot rock potential = 63 TW.

Geothermal is the backbone — unlimited baseload, available everywhere, existing pipeline infrastructure repurposed. Drill once, power forever. Pipeline workers honored and employed in the transition.

Supplemental Sources

Surface solar: dual-use only — agrivoltaics over agricultural buffer zones and building integration. Standalone solar fields are not used — that land grows plants. Wind, tidal, and wave energy contribute during the transition period but are phased down over time in favor of geothermal and solar, which have no moving parts exposed to weather and require less maintenance — consistent with the thousand-year infrastructure philosophy. A long-term efficiency comparison of renewable energy capture methods across multi-century timescales (maintenance, replacement cycles, lifetime energy output) is flagged for the institution’s research program.

Long-Term Temperature Management: Space Shades at L1

Space shade array: ~100,000 tonnes total at L1. Borgue & Hein (2022) confirmed this mass for ultra-thin polymeric films with SiO₂ nanotubes. 50–100 year project. Temperature management, not energy generation.

Moon-anchored spaceline: Feasible with current materials (Zylon, Dyneema). Pearson et al. (2005, NASA NIAC), Penoyre & Sandford (2019), JBIS (2023). 48-ton system deployable via single heavy-lift launch. 20–30 year development timeline.

Deep City Geothermal Integration

Pyramid city infrastructure extends 1–2 km below surface. At 2 km depth, ambient rock temperature is ~60–80°C (geothermal gradient ~25–30°C/km). Geothermal drilling from the base requires 1–2 km less depth to reach superhot conditions. City and energy system integrated by design.

City Energy Storage

Pumped hydro (elevated reservoirs and turbines), gravity batteries (heavy masses on cables including construction waste — nothing to break, unlimited cycles), compressed air, thermal storage.

Transport

Robo taxi fleet: Replaces private car ownership. ~80% vehicle fleet reduction. One shared autonomous vehicle replaces 4–12 private cars (Scientific Reports 2025; PMC 2022). Parking demand reduced 80–90%.

Roads and parking reclaimed: Significant land returned to ecosystem.

Manufacturing CO₂ saved: ~9,600 Mt one-time avoided emissions. Derivation: ~1.2 billion vehicles eliminated from fleet × ~8 tonnes CO₂ lifecycle manufacturing emissions per vehicle. One-time saving from not replacing these vehicles over their typical lifecycle.

PART TWO: FOOD AND LAND — THREE-ZONE MODEL

Zone 1: Underground Core

Primary calorie production: tubers (potato, sweet potato, cassava) in aeroponic tier systems. Protein: legumes, insect larvae (black soldier fly), aquaponics. Diversity: leafy greens and herbs in vertical panel systems. Mushrooms including light-requiring gourmet species (lion’s mane, maitake, shiitake) integrated via CO₂ cascade — mushrooms in upper tiers respire CO₂ that falls onto photosynthesizing greens below (original TC permaculture-CEA integration). Fruit crops in trellis and vertical systems.

Tier configuration: 6–8 effective growing tiers. Thermal management via underground rock mass as initial heat sink, transitioning to geothermal heat exchange at steady state. Blended yield: ~50,000–100,000 kcal/m²/yr of floor space.

Zone 1 floor area: ~60,000–110,000 km².

Zone 2: Surface Agricultural Buffer

Grains (wheat, rice, oats, barley, corn) under agrivoltaic arrays around cities and villages. Low-height autonomous tractors. Distributed hobby farming with domestic livestock as living genetic libraries. Orchards and perennial food forests as permaculture transition: city fades into food forest fades into restoration ecosystem.

Zone 2 area: ~2–4 million km² (~1.5–3% of habitable land).

Zone 3: Wild Harvest

Hunter-steward model integrated with restored ecosystems. Wild game, marine harvest, wild-harvested plants, berries, nuts. Substantial in a world with 90% restored ecosystem.

Total Agricultural Footprint

Total: ~2.5–4.5 million km², or ~2–3.5% of habitable land.

Agricultural land freed: ~44–46 million km² returned to native ecosystem (~90–95% of current agricultural land).

Design Integration

Biodigester-concrete cycle: food waste → anaerobic digester → biogenic methane → combustion CO₂ → carbonation curing in concrete → permanent mineralization. Carbon-negative production cycle. Co-locate biodigester and concrete plant for direct output-to-input flow.

PART THREE: THE CARBON SEQUESTRATION STACK

V7 replaces the flat annual rate with a time-varying curve incorporating land availability ramp-up, ecological maturity, and natural disturbance regimes. All layers operate simultaneously at full deployment.

Layer 1 — Stop Emitting

Full renewable transition. Necessary but not sufficient — methane feedbacks already triggered.

Layer 2 — Ecosystem Restoration (Primary Engine) — TIME-VARYING

### Land Availability Ramp-Up

Wave 1 (Years 0–30): Marginal pastureland released first. ~5–10M km² begins restoration.

Wave 2 (Years 30–80): Cropland liberation. ~60–70% of agricultural land released by year 80.

Wave 3 (Years 80–150): Social transition tail. 90% restoration by ~year 150.

### Composite Sequestration Curve

| --- | --- | --- | --- |

| Years 0–30 | ~5 | ~0 | Small area, early growth. Transition emissions still high |

| Years 30–80 | ~30 | ~21–26 | Maximum land in peak growth. Highest net drawdown |

| Years 80–200 | ~25 | ~16–21 | All land restoring; earliest parcels maturing |

| Years 200–400 | ~15 | ~10–15 | Mid-to-late succession. Fire mosaics cycling |

| Years 400–700 | ~5 | ~4–6 | Long tail. Wetland peat accumulation continues |

| Years 700+ | ~0 | ~0 | Dynamic equilibrium |

Natural disturbance regimes (fire return intervals 1–500 years by biome, plus windthrow, landslides, storms) maintain landscape-level sequestration through mosaic age classes in fire-adapted biomes. Grassland fires release aboveground carbon but preserve soil carbon. The mosaic effect partially offsets declining rates from tropical forest maturation.

Published comparison: Lewis et al. (2025, Nature Geoscience) found 96.9 GtC total through 2100 at 15–30% restoration. TC restores 90% — 4–6× more land. Scaling brackets TC central estimates. No published study has modeled 90% restoration at multi-century maturity. Additional support: Griscom et al. (2017, PNAS), Cook-Patton et al. (2020, Nature), IPCC AR6 WGIII Ch. 7.

Layer 3 — Enhanced Weathering

+2.0 GtCO₂/year. Upper end of Beerling et al. (2020, Nature) range of 0.5–2.0. Defensible in TC scenario with unlimited clean energy and no cost constraint.

Layer 4 — CO₂-Absorbing Concrete

During production: ~30–40 GtCO₂ one-time via carbonation curing (45% efficiency, Fu et al. 2024) over the 100–200 year construction period.

During lifetime: +0.5–1.0 GtCO₂/year continuously from mature TC infrastructure stock. Huang et al. (2025, ESSD) found current cement materials absorb 0.86 GtCO₂/yr globally from ~300 billion tonnes of stock. Estimated TC concrete stock: 10–20 trillion tonnes (pyramid cities, tunnel systems, floating city foundations, thousand-year infrastructure). Scaling suggests carbonation contribution may be higher than stated; conservative estimate retained pending formal derivation.

All concrete production zero fossil carbon. Basalt fiber reinforcement (~70–90% less CO₂ than steel, Kingston University LCA; production comparison 0.5–0.7 vs 2.2 tCO₂/tonne). Recycled aggregate from old infrastructure. CO₂ for curing from biogenic methane combustion.

Layer 5 — Direct Air Capture

+1.0 GtCO₂/year supplemental. IEA NZE scenario: ~980 MtCO₂/yr by 2050. Conservative. With unlimited clean energy, DAC significantly more feasible.

Dedicated Underground Algae — ELIMINATED

Rigorous analysis showed energy cost of underground algae at climate scale is prohibitive. Same energy produces 10× more removal via DAC. Same land area produces comparable removal via surface ecosystem restoration at zero energy cost. Preserved as documented elimination.

Surface and Ocean Algae

Supplemental tool subject to significant uncertainty. Not carried as specific line item. Ocean-based biological carbon removal noted for further research.

Negative Feedbacks

Arctic methane: ~5 GtCO₂e/yr (range 2–8). Permafrost thaw already triggered; persists centuries. Schuur et al. (2022), Hugelius et al. (2024), Yuan et al. (2024). Over 30% of Arctic-Boreal now net source (ICCI 2025).

Ocean outgassing: ~4 GtCO₂/yr (range 2–6). Carbonate buffer chemistry resists equilibrium change. Currently ocean absorbs ~2.9 GtC/yr (Global Carbon Budget 2024); reverses as atmospheric CO₂ drops. Holzer & DeVries (2022). Specific rate during rapid drawdown is original TC analysis.

Net Sequestration Summary

Integrated total net capacity: ~4,000–6,000 GtCO₂ over the full timeline — well in excess of the ~2,680 GtCO₂ required. The framework has margin. Peak net drawdown of ~21–26 GtCO₂/yr during years 30–80 replaces the previous flat estimate.

PART FOUR: SOLAR RADIATION MANAGEMENT

Marine Cloud Brightening (MCB)

Salt spray into low marine clouds. Immediate deployment. Core coral and Arctic protection. Feingold et al. (2024, Science Advances): 31-scientist consensus roadmap. Harrison et al. (2020): proof-of-concept on Great Barrier Reef. Latham et al. (2013): sub-global MCB ameliorates coral bleaching. Lower governance complexity than SAI. Continues indefinitely as ecosystem support.

Stratospheric Aerosol Injection (SAI)

Global temperature bridge. Deployed years 0–2. Delivery: high-altitude balloons, solar-electric aircraft (Airbus Zephyr at 21 km), synthetic biofuels. Not biomethane — reserved for rockets only. Duffey et al. (2025, Earth’s Future): low-altitude SAI feasible with existing aircraft. Smith (2020, Environ. Res. Lett.): ~$18B/yr per °C avoided. Purpose-built fleet: 1–2 decades.

SAI handoff to L1 shades: Years 100–120, with 20–40 year overlap. Spaceline operational by ~year 25–35, lunar manufacturing by ~year 40–60, shade deployment gradual.

SRM Moderate Overshoot Cooling — NEW

TC proposes moderate radiative forcing overshoot: SAI and L1 shades cool 0.5–1.0°C below natural trajectory during peak drawdown (years 30–200). Not cooling to pre-industrial — controlled over-correction to accelerate ocean heat release. Cooler atmosphere steepens thermal gradient, speeds ocean-to-atmosphere heat transfer.

Trade-off: Reduced photosynthetically active radiation may slow ecosystem growth. Requires quantification.

Monsoon sensitivity: SAI must avoid disrupting monsoon patterns. Hemispheric symmetry reduces risk. Underground food reduces agricultural monsoon dependency. Calibration is critical constraint during transition.

Original TC analysis. No published literature addresses over-cooling during multi-century drawdown. Genuinely new territory.

Cirrus Cloud Thinning (CCT): Early research. Supplemental. Thins high cirrus to allow more outgoing longwave radiation.

Biomethane: Upgraded to 99.5% purity. Rockets only. Carbon neutral.

PART FIVE: SEA LEVEL RISE

Permanent on any human timescale. TC floor ~2.0–2.2m above 2024 baseline. Coastal abandonment is rational. TC builds inland. Projections consistent with IPCC AR6 WGI, SROCC, WCRP (2022).

| --- | --- | --- | --- | --- |

| 2050 | 0.25m | 0.18m | ~50,000 km² | ~60M |

| 2100 | 1.1m | 0.55m | 132,000 km² | 165M |

| 2200 | 4.5m | 1.5m | 720,000 km² | 900M |

| 2300 | 7m | 2.0m | 1,200,000 km² | 1.5B |

PART SIX: THE FULL TIMELINE

Year 0: Decision. MCB and SAI deployed. Grid decarbonization begins.

Years 0–30: Temperature still rising 0.3–0.5°C (underlying; SRM-masked surface may be held stable). Tell people now. Sea level: 3–5 mm/yr. Pastureland restoration begins.

Years 30–60: Emissions ~55 → 5 GtCO₂e/yr. Pyramid cities 30–50% populated. Major cropland liberation.

Years 60–120: Near-zero emissions. CO₂ at peak ~460–500 ppm (depends on transition speed; faster reductions yield lower peak).

Years 100–120: SAI hands off to L1 space shade array (20–40 year overlap transition).

Years 120–200: Active drawdown. CO₂ falling. Earliest restorations beginning to mature.

Years 200–400: CO₂ approaching overshoot target of ~250 ppm.

Years 400–700: CO₂ overshoot held. Temperatures finally falling. Sea level plateau ~2m. L1 shades phasing down. Ecosystems maturing. CO₂ recovering toward 280 ppm.

Years 700–1000+: Full planetary climate stabilization. Sea level permanently elevated.

Temperature Recovery

Ocean has absorbed >90% of excess heat. Deep ocean equilibration: 500–1,000 years. Surface air temperatures may not return to 1950s levels (~0.2°C above pre-industrial) until roughly years 300–500. Extreme weather persists for generations. Confirms necessity of thousand-year infrastructure.

PART SEVEN: OCEAN INTERVENTIONS

Artificial Upwelling (AU): Cold deep water pulses reduce coral bleaching. Sawall et al. (2020, Frontiers Mar. Sci.): <2 hrs/day significantly reduces stress. Feng et al. (2020): can prevent bleaching through 2099 under certain scenarios. NOT effective for carbon sequestration — may upwell dissolved inorganic carbon. Use: targeted coral protection only.

Whale pump: Restoring whale populations = natural iron fertilization. Lavery et al. (2010, Proc. R. Soc. B): 50 tonnes Fe/yr from 12,000 Southern Ocean sperm whales. Feces 10 million × richer in iron than seawater. Net ~200,000 tC/yr; ~2M tonnes at pre-whaling levels. Ecosystem restoration strategy with carbon co-benefits — not primary carbon tool (Boor et al. 2023 caveat noted).

MCB: See Part Four.

Iron fertilization: Mixed trial results. Supplemental, monitored, limited locations. Not primary strategy.

PART EIGHT: CO₂ BUDGET AND OVERSHOOT

Current State

CO₂: ~427 ppm (early 2026), 50%+ above pre-industrial 280 ppm. 1 ppm = 7.82 GtCO₂ (CDIAC). Total GHG emissions: ~55 GtCO₂e/yr (EDGAR 2025: 53.2 excl. land use; Climate Change Tracker: 56.4 incl. all sources). Energy CO₂ only: 37.8 GtCO₂/yr (IEA 2025). Cumulative since 1850: ~2,650 GtCO₂ emitted, ~1,050 GtCO₂ remaining in atmosphere (Global Carbon Budget 2024).

Total CO₂ to Sequester: ~2,680 GtCO₂

Includes atmospheric excess above overshoot target, ocean outgassing resistance over centuries, and continued emissions during transition. Original TC derivation.

CO₂ Overshoot Target: ~250 ppm

Below pre-industrial 280 ppm to compensate for thermal lag, but above levels causing C3 plant stress. Poorter et al. (2022, New Phytologist): C3 stress below 200 ppm, compensation point 35–60 ppm. Tolbert et al. (1995, PNAS): at 220 ppm, O₂ compensation approaches atmospheric levels. At 250 ppm, C3 plants (85% of species) function with reduced but adequate productivity. Held ~100–250 years, then CO₂ recovers to 280 ppm. Exact target requires modeling of restored ecosystem responses at sub-pre-industrial CO₂ — genuinely uncharted territory.

PART NINE: WHAT REMAINS FOR V8

Energy budget formal derivation: Table included in V7; detailed sector-by-sector write-up with full justification for each estimate.

Food system computational model: Volume-based derivation with crop matrices, tier optimization, and thermal modeling.

Sequestration curve quantitative model: Computational model of composite curve for peer review presentation.

Concrete stock estimation: Formal derivation of TC infrastructure tonnage (~10–20 trillion tonnes preliminary). Implies carbonation contribution may exceed stated 0.5–1.0 GtCO₂/yr.

SRM overshoot modeling: Ocean heat release acceleration vs. photosynthetic productivity reduction trade-off.

Monsoon sensitivity analysis: SAI calibration constraints for monsoon-dependent regions during transition.

C3 ecosystem modeling at ~250 ppm: Restored ecosystem productivity at sub-pre-industrial CO₂.

Renewable energy long-term comparison: Multi-century efficiency comparison of geothermal, wind, and solar: maintenance, replacement cycles, lifetime output. Expected to confirm wind phase-out.

City design exploration: Deeper investigation of pyramid city geometry, underground integration, cultural diversity in architectural expression.

Version 7 | March 2026 | Working Document — Not for Distribution

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