OCEI™ v2.0 — Orbital Compute Efficiency Index
Formal 1,000-Point Thermodynamic, Radiative, Optical & Token-Economic Methodology Specification
1. Purpose & First-Principles Normalization
Conventional terrestrial metrics such as PUE (Power Usage Effectiveness) fail to capture the physics of orbital AI data centers, where solar irradiance is unattenuated (+30% AM0 constant), heat is rejected into vacuum via fourth-power Stefan-Boltzmann radiation (∝ T4) with zero water consumption, inter-rack tensors propagate through free-space lasers at +46.8% higher velocity than silica glass fiber, and high-energy solar protons (≥10 MeV) require dynamic Young-Daly distributed checkpointing.
The Orbital Compute Efficiency Index (OCEI v2.0) establishes a rigorous, reproducible 1,000-point composite benchmark (composed of four equi-weighted 250-point physical pillars) that evaluates any orbital or terrestrial compute regime in real time using six live NOAA Space Weather Prediction Center (SWPC) and GOES satellite telemetry streams.
2. Mathematical Specification of the Four 250-Point Pillars
Evaluates unattenuated solar flux IAM0 = 1,361 + 0.08(F10.7 − 150) W/m², orbital illumination duty cycle (99.8% in 650 km Dawn-Dusk Terminator SSO vs. 68.0% in inclined LEO), battery eclipse mass elimination (−94%), and zero marginal fuel/grid OpEx ($0/MWh vs. $115/MWh firm terrestrial industrial power).
Governed by two-sided radiative heat rejection into the 200 K orbital sink: q = 2εση(Tloop4 − Tsink4) (σ = 5.6704×10−8 W·m−2·K−4, ε = 0.92, η = 0.85), yielding 1,237.5 W/m² at 80°C, an orbital PUE of 1.018 (vs. 1.320 terrestrial), and 0.00 L/kWh water usage (saving 1.58B liters/yr per 100 MW).
Captures the physical trade-off where Earth's atmosphere shields silicon (248.0/250), whereas orbital clusters face solar protons (≥10 MeV flux Φp and geomagnetic Kp). Computes cluster Double-Bit Error MTBF and the Young-Daly optimal checkpoint interval τopt = √(2δ · MTBF) across 1.6 Tbps OISL links (δ = 0.45 min).
Measures free-space optical inter-satellite link (OISL) propagation at vacuum light speed (c = 299,792.5 km/s vs. 204,190.5 km/s in n = 1.4682 silica fiber, a +46.8% physical speed advantage), 0.50 μs close-formation swarm AllReduce latency, and bypassing the 36-to-48 month terrestrial utility interconnection queue.
3. Space-Weather Stress-Test Matrix (100 MW Vera Rubin NVL72 Cluster in 650 km SSO)
| Space-Weather Regime | OCEI v2.0 Score | Spread vs. Earth | SEU MTBF / Young-Daly τopt | Net Compute Avail. | 5-Yr $/1M Tokens |
|---|---|---|---|---|---|
| G0 Quiet Solar Minimum (Kp 1.0, 0.4 pfu) | 972 / 1000 | +442 bps | 181.2m / Every 12.8m | 97.62% | $0.5213 / MTok |
| Live NOAA Satellite State (Kp 1.4, 0.25 pfu) | 970.4 / 1000 | +440.4 bps | 168.8m / Every 12.3m | 97.57% | $0.5215 / MTok |
| G3 / S2 Strong Solar Storm (Kp 7.0, 120 pfu) | 905.7 / 1000 | +375.7 bps | 36m / Every 5.7m | 92.84% | $0.5481 / MTok |
| G5 / S4 Carrington Superstorm (Kp 9.0, 2,500 pfu) | 857.1 / 1000 | +327.1 bps | 18.1m / Every 4m | 90.04% | $0.5652 / MTok |
| Terrestrial Tier-IV Grid Baseline ($115/MWh, PUE 1.32) | 530.0 / 1000 | 0.0 bps (Reference) | Atmospheric Shielding (248.0/250) | 99.10% | $0.9696 / MTok |
4. Standard Citation & Live SVG Badge Embed
Spatial Compute Holdings, "OCEI v2.0: Orbital Compute Efficiency Index — Real-Time Thermodynamic, Radiative & Token-Economic Benchmark," OrbitCompute.ai, 2026. Available: https://orbitcompute.ai/ocei
[](https://orbitcompute.ai/ocei)