What is connected to what, and at what voltage.

AEMO took its single-line diagrams offline in early 2022 and its interactive map cannot be downloaded, so there is no official machine-readable answer to “what is Eddington connected to”. This is assembled from Geoscience Australia’s open Electricity Infrastructure layers, which publish substations as points and lines as polylines — but which record no connectivity at all.

The connections are recovered two ways, and the two are checked against each other. GA’s digitisers snapped line ends onto substation points, so half of all endpoints sit at exactly zero distance from a station and 94% within 500 m; that gives the topology. Separately, lines are named “Wodonga Terminal to Jindera”, so the endpoints are also written down in prose. The two agree on 440 of the 464 lines where both can be read.

Nearly all of the 24 disagreements are spelling — Millmerrin for Millmerran, Dumaresq for Dumeresq, Templstowe for Templestowe — or a name that has aged: lines still labelled for Swanbank B and Torrens A land on the stations that replaced them. In those cases the geometry is the better witness, and the geometry is what is drawn. The build script prints every disagreement rather than hiding it.

Two things are deliberately excluded. Lines whose ends snap to the same station are dropped: they are the stub between a power station and its own switchyard, real plant but not a corridor. And the map stops at 220 kV: including 132 kV would take it from 465 lines over 270 stations to 1,153 over 717, a different and much less legible picture.

Two things fall through that floor, and both mislead if you do not know. Directlink, the second NSW–Queensland interconnector, is ±80 kV DC and runs at 110–132 kV the whole way from Mullumbimby through Bungalora and Terranora to Mudgeeraba, so none of it qualifies. That is why the map shows QNI as the only path into Queensland, and why it stops at Lismore — which genuinely is the top of the 330 kV network, but not the end of the network. Tasmania’s 110 kV network is missing for the same reason, so a few Tasmanian stations look lonelier than they are.

Murraylink does not fall through, but nearly did. GA records a converter station’s AC terminal voltage rather than its DC rating, so Murraylink is filed as a 220 kV line from Monash to Red Cliffs and drew as an ordinary Victorian circuit until it was named explicitly. Basslink only stood out by luck, its 400 kV being unique on the network. Both are now listed by name in the build script rather than inferred, and the check step fails loudly if either name stops matching.

Both data files are served from this site, not fetched from GA on page load. What you are looking at is a dated snapshot, and the archived upstream bytes sit in the repository beside it.