Guide · Orientation
Written for: seed / Series A scientist-founder
The handbook uses one running example throughout: ammonia. It’s chosen because a single, familiar product spans the three worlds a climate TEA has to reason about — a fossil route (gray), a carbon-capture route (blue), and an electrified route (green) — so almost any concept, from a recycle loop to a carbon credit, can be illustrated on the same backdrop without re-introducing a new process each time. When an example is needed anywhere in the handbook, reach for ammonia first.
All three routes share the same skeleton: make hydrogen, get nitrogen from air, and react them in a high-pressure synthesis loop.
H₂ source → (CO₂ capture, blue only) → mix with N₂ from air → synthesis loop → condense out NH₃ → recycle the rest.
The synthesis loop is the heart of it and is identical across all three colors: a 3:1 molar H₂:N₂ feed reacts at high pressure, only ~20% converts per pass, the ammonia is condensed out, and the unconverted gas is recycled with a small purge to keep inerts from building up. Lift the overall conversion to ~98% and you have the whole plant in a sentence.
This is the single most useful thing to hold about the example: the routes differ only at the hydrogen source and the CO₂-capture block. Everything downstream is the same plant.
That structure is what makes ammonia such a clean teaching case: when green and gray differ in cost or carbon, you can point to exactly where — the front end — because the synthesis loop they share cancels out. It’s the structural-layer “locate the delta” move, built into the example.
| Parameter | Value |
|---|---|
| Product | ammonia, NH₃ |
| Routes | gray (SMR H₂) · blue (SMR + CO₂ capture) · green (electrolytic H₂) |
| Synthesis stoichiometry | N₂ + 3H₂ → 2NH₃; loop feed H₂:N₂ ≈ 3:1 molar |
| Where routes differ | the H₂ source and the CO₂-capture block only |
| H₂ content of NH₃ | ~0.176 t H₂ / t NH₃ |
| Electrolytic O₂ co-product (green) | ~8 kg O₂ / kg H₂ (≈ 1.4 t O₂ / t NH₃) |
These are the illustrative figures the mini-examples lean on across the handbook. They are round anchors, not validated facts — every one is provisional (⏳) and flagged for validation until an expert confirms it.
| Anchor | Working value |
|---|---|
| Representative nameplate | ~1,000 t/day NH₃ |
| Per-pass / overall conversion | ~20% / ~98% (with recycle) |
| Capacity factor — gray / green | ~0.90 / ~0.3–0.5 |
| Green electricity intensity | ~10 MWh / t NH₃ |
| Low-carbon electricity price | ~$40 / MWh |
| Green levelized cost (gross, CF 0.90) | ~$800 / t NH₃ (±~30%) |
| Green levelized cost, net of clean-H₂ credit | ~$260 / t NH₃ |
| Gray production cost (benchmark) | ~$200–400 / t NH₃ (gas-price-dependent) |
| Gray carbon intensity | ~1.6–2.4 t CO₂e / t NH₃ |
🧭 Coach’s Read. Treat these numbers the way the handbook asks you to treat your own: as illustrative anchors carrying a real ±band, never as settled truth. If those deliberately-round figures make you twitch a little — good, that’s the scientist in you, and it’s the right instinct pointed the wrong way: the cure for an uncomfortable number isn’t more decimal places, it’s keeping the ±band stapled to it. The green ~$800/t and the ~$260/t net are a coherent, deliberately-rounded story — green ammonia is ~2–3× the cost of gray today and is brought close only by a policy credit — not a market quote. They exist to make the method concrete, so when you swap in your own process and your own validated figures, the worked logic carries over even though the numbers won’t. If you quote one of these as a fact, you’ve made exactly the false-precision mistake the example is trying to teach you to avoid.
A note on the canonical sheet: this page is the narrative home of the running example, and the full, single-source reference sheet — every figure, what uses it, and its validation status — currently lives in the build context (04_CONVENTIONS.md 6) and is slated to migrate here. All mini-examples draw from that one sheet by design, so the figures never quietly contradict; nothing on a concept page should invent a conflicting ammonia number.
That’s the whole backdrop. Now the layers begin, each run once on this example: Layer 1 — Structural Layer, where ammonia gets decomposed, bounded, scaled, and laid beside its incumbent.