Node Performance Criticality
Every gas node is scored on four signals: the urban population it serves, how far it sits from the nearest electricity supply point, what its failure does to the hydraulic model - which nodes lose supply altogether, and which stay connected but drop below the pressure they need - and the national import volume its failure would strand.
How the isolation impact is calculated
The deliverable-pressure field is solved for the live network, then re-solved once for each node with that node and its pipelines out of service. Comparing the two solves gives the nodes cut off from every live entry point, the nodes still fed but losing more than 5 bar of deliverable pressure, and the nodes that survive only by switching to a different supply front. Decommissioned assets are excluded from both solves.
Why interconnectors and supply points rate highly
Landfalls, interconnector terminals and their single-fed corridors serve almost no local population, so density and local isolation alone rate them as unimportant. A fourth signal measures import dependence: each node is tested for the supply points it strands - those that can no longer reach any demand centre once it is out of service - and credited with their arriving volume in GWh/day, expressed as a share of total live national entry volume. Every supply-side asset is simulated even where it carries a single pipeline, which previously excluded them from the scan entirely.
Indicative scoring only
Population figures come from crowd-sourced OpenStreetMap settlement data with estimates where population tags are missing, and the network topology is incomplete. Scores illustrate the method, not the true criticality of live assets.
| # | Node | Type | Population served | Nearest power supply | Supply at risk | Loses supply | Loses pressure | Score |
|---|---|---|---|---|---|---|---|---|
| Re-solving the hydraulic model for every node… | ||||||||
Score = 25% urban density served + 10% electrical proximity risk (distance to the nearest substation, saturating at 25 km) + 40% hydraulic isolation impact - loss of supply at full weight and loss of pressure at 40% - plus 25% import dependence, the share of live national entry volume stranded by the failure. Each signal is normalised and compressed so one dominant node does not flatten the rest. Select a row to pin that node on the map.