Semantic layer • the graph
The relations graph
Every node is an entity in the site's registry and every line a typed relation between two of them. Two provenances, kept apart: hand-authored relations someone asserted and sourced, and derived relations the registry itself implies (a facility's operator, its receptor water, a country's bloc membership), each tagged with the file it was expanded from. Two kinds of line, also kept apart: structural relations are definitional or legal and carry no confidence, while causal relations license a counterfactual and carry one. Everything passes the same build gates; nothing here is drawn by hand, and the picture grows denser with every build.
This build: 190 entities · 312 typed relations (98 hand-authored, 214 derived with provenance; 261 structural, 51 causal) · 7 dependency edges with pre-registered falsifiers on the Forecast Lab.
How to read this
Click a node to see its relations, then focus the view to redraw its whole neighbourhood as rings around it. Scroll or use the corner buttons to zoom; drag the background to pan. Node size is the number of relations; colour is the entity type. Grey lines are structural (definitional or legal), coloured lines are causal: measured solid, inferred dashed. Relations marked "derived" were expanded from the registry with their source file as provenance.
Most connected this build:
- (30)
- (28)
- (19)
- (12)
- (11)
- (11)
Worked example: , with its mines, operators, receptor lakes and the metals they feed.
The cost trace: a shock walked through the graph
The causal edges above state that a link exists; these are the ones quantified into transfer functions, each coefficient sourced from data already published on this site and validated at build. Pick a carbon-price shock and follow it. Every hop carries a range, and a chain multiplies its hops' ranges, so the further downstream you read, the wider the honest answer gets. Where the interval is embarrassingly wide, that is the finding, not a display bug.
Chain · EUA → wholesale power → green hydrogen
EUA price into the wholesale power price
◐ inferredmechanismPass-through 0–1 (mid 0.37) EUR/MWh per EUR/tCO2
+10.0 EUR/tCO2 -> 0 to +10.0 EUR/MWh (+3.70 in a gas-set hour)
Merit-order arithmetic: in any hour the pass-through equals the price-setting plant's emission intensity. Zero when hydro, nuclear or wind set the price; about 0.34-0.41 tCO2/MWh of electricity when a gas CCGT does (natural gas ~0.20 tCO2 per MWh of fuel at 50-60% electrical efficiency); about 0.9-1.0 when coal does. The mid value is the gas-marginal hour. An annual average therefore depends on how often fossil plant is marginal in the bidding zone, which this registry does not yet measure.
↓
Wholesale power price into green-hydrogen production cost
◐ inferredmechanismPass-through 0.047–0.06 (mid 0.055) EUR/kg H2 per EUR/MWh
-> 0 to +0.60 EUR/kg H2 (+0.20 via the gas-set mid), electricity component only
Specific electricity consumption of electrolysis: this site's electricity-costs dashboard and hydrogen brief use 55 kWh per kg of hydrogen (PEM, ~70% efficiency), so one EUR/MWh moves the electricity component of a kilogram of hydrogen by 0.055 EUR. The range spans efficient alkaline (47 kWh/kg) to less efficient PEM (60). Electricity component only, not an all-in production cost.
Note how the interval widens hop by hop: the first hop's range is the marginal-plant question, and the second inherits it in full. Two mechanism-identified hops compound to a range, not a number; making hop one measured (counting fossil-marginal hours in a bidding zone) is the registered refinement.
Statutory · EUA → CBAM cost of imports
Steel · China, BF-BOF route
● measuredstatutory+10.0 EUR/tCO2 → +0.45 to +0.58 EUR/t steel in 2026
Embedded intensity 1.8–2.3 tCO2/t; at the current EUA price the mid-intensity CBAM cost is about 3.97 EUR/t steel in 2026. Origin changes this several-fold.
Cement · Turkey
● measuredstatutory+10.0 EUR/tCO2 → +0.18 to +0.23 EUR/t cement in 2026
Embedded intensity 0.7–0.9 tCO2/t; at the current EUA price the mid-intensity CBAM cost is about 1.51 EUR/t cement in 2026. Origin changes this several-fold.
Aluminium · China (coal-grid smelting)
● measuredstatutory+10.0 EUR/tCO2 → +4.00 to +5.00 EUR/t aluminium in 2026
Embedded intensity 16–20 tCO2/t; at the current EUA price the mid-intensity CBAM cost is about 34.0 EUR/t aluminium in 2026. Origin changes this several-fold.
Coefficients: this site's CBAM intensity table (IEA, World Steel, GCCA GNR, IAI) and statutory phase-in schedule under Regulation (EU) 2023/956; merit-order arithmetic with IPCC default fuel factors; the 55 kWh/kg electrolysis assumption from the electricity-costs dashboard. All ranges live in the registry (cost-edges.json) behind the same build gate as the graph; a coefficient without a source cannot enter.
What keeps this honest: a relation cannot enter the registry unless both entities resolve and its predicate is declared, a structural relation is forbidden from carrying confidence, derived relations name the file they were expanded from, and the build fails on any violation. The layer above this graph, dependency edges with mechanisms and pre-registered falsifiers, lives on the Forecast Lab and the mine-water worked example.