An open calculator for the orbital-vs-terrestrial carbon break-even of AI compute.
OrbitOrEarth accompanies the paper "When Does AI Compute Belong in Orbit? A Workload-Conditioned, Multi-Criteria Decision Framework for Orbital Data Centers." It turns the paper's per-kilowatt lifecycle break-even model into an interactive decision tool and reproduces every figure and number reported in the manuscript.
The central finding is that the order-of-magnitude disagreement in the literature over orbital-data-center carbon reduces to a choice of accounting boundary and climate metric. The calculator makes that choice an explicit, movable axis: load the optimist (NTU) or the pessimist (Saarland) preset and watch the verdict flip.
| File | Purpose |
|---|---|
orbitorearth.html |
Self-contained interactive calculator. Open in any browser, no install. |
model.py |
The break-even model. Central equation: I* = (M*f + B - D) / (PUE*H*L*U). |
params.yaml |
All model parameters with value, low/high range, unit, source, and status. |
sweep.py |
Generates the sensitivity sweep, the tornado diagram, and the break-even map (300 DPI). |
test_model.py |
Reproducibility checks: the model reproduces the optimist, pessimist, and reference verdicts. |
requirements.txt |
Python dependencies for regenerating the figures. |
The calculator. Open orbitorearth.html in a web browser. Move the sliders (system mass, hardware lifetime, forcing multiplier, PUE, utilization, grid intensity), toggle the accounting boundary and the climate metric, or load a preset. The orbit-or-ground verdict, the break-even intensity I*, the Monte-Carlo interval, and a confidence label all update live.
The figures.
pip install -r requirements.txt
python sweep.py
This writes the paper's figures to figures/.
Every parameter in params.yaml carries a source and a status field (sourced, estimated, or preliminary). The forcing multiplier, the orbital-manufacturing term, the avoided-construction term, and the per-kilowatt water term are documented as preliminary. Substitute your own estimates and the verdict updates accordingly.
If you use OrbitOrEarth, please cite the archived release:
[Author], OrbitOrEarth: A Workload-Conditioned, Multi-Criteria Decision Calculator for Orbital Data Centers, 2026. Zenodo. DOI: 10.5281/zenodo.XXXXXXX
Replace the DOI above with the one Zenodo assigns, and add the DOI badge here once the release is created.
Released under the MIT License. See LICENSE.