GB reduced model
The NESO reduced GB model — interactive and in context.
The current centre piece of the site is a 28-zone representation of the GB transmission system derived from the NESO public release in DIgSILENT PowerFactory. It is important to note that the model released by NESO is a very simplified model, and combined the GB network into a series of smaller amalgamated and aggregated systems, but it is a useful research tool for representing complex systems behaviour, and can be used to give a flavour of the UK operating behaviour and performance.
The AI aspect of this piece of the work is a direct MCP interface between the various analysis AI and the Powerfactory implementation, this allows me to run complex analysis cases directly as command line prompts and pass direct results into the AI for assessment and observation. This level of analysis is the next stage of power system analysis in future networks, massive automation and simplicity. We instruct the AI what study types we want to see and trends, and get the AI to execute the commands in the software and filter the results back to us, flagging any areas of interest or concern.
The interactive map below combines synchronous inertia, demand, generation mix, 400 kV corridors, HVDC interconnectors and six dispatch scenarios in one view. Beneath it sits the context needed to interpret what the map shows, the model’s structure, the data behind each layer and the honest caveats that go with a reduced representation.
Model context
What the model represents and how to read it.
Purpose
The 28-zone representation of the GB transmission system should not be confused with the real system, it is necessarily simplified a great deal. It is intended to give researchers and developers a flavour of the UK system and allow research and development ideas to be generated and tested. For example the model shows a single line from Scotland (Zones 27 & 28) to North England - this is not correct, and there are multiple paths; however there is a well-known stability limit down these lines, which is represented by the aggregated equivalent.
The key value is that the 28 zone model it is a large enough system to see complex transmission effects and behaviours and look at issues like generation forecasting, broad dispatch scenarios, system strength, inertia distribution and exploratory what-ifs for increasing penetration of GFM technology or sudden changes in inertia. It is not really intended for formal RMS or EMT work that would be used to shape policy or operation.
Model structure
28 zones anchored at representative 400 kV substations, 46 retained 400 kV corridors plus the West Coast HVDC link and 10 interconnectors. Loads, generation across seven technology categories, and synchronous inertia are aggregated to zone level from the underlying PowerFactory project (326 machines). Each substation contains various generation technology types that can be configured for different generation loading cases and scenarios. The generation controllers are based on generic open IEEE and WECC models.
Filters allow heatmaps to be switched on and off for load and different generation types; key line ratings of the transmission system and HVDC links are also included. The map carries four baseline dispatch scenarios — winter high-wind, winter low-wind, summer high-RE, summer low-RE — plus two wind-constrained variants that curtail Scottish wind against a B6-style boundary to illustrate the effect on inertia and zonal balance. Six loading scenarios are considered:
- Winter High Wind (High Demand)
- Winter Low Wind (High Demand)
- Summer High Wind (Low Demand)
- Summer Low Wind (Low Demand)
- Summer High Wind (Low Demand) — Constrained by Inertia
- Summer Low Wind (Low Demand) — Constrained by Inertia
Each scenario carries scaled load and generation heatmaps, HVDC flow arrows, 28 draggable zone-summary cards, and (where applicable) a wind-constraint overlay
Assumptions and limits
Equivalent-machine inertia uses H = 5.0 s across all TypSym entries, giving ~287 GVA·s at baseline — on the high side; 230–260 GVA·s is more realistic with per-tech H. Summer scenarios currently capture the inertia envelope only; thermal boundary limits (e.g. B6) are not yet enforced. Offshore wind markers stay at baseline even under scaled scenarios.
Curtailment scenarios (5 & 6) consider minimum inertia levels given in the NESO FRCR of 110GVA.s. When time is permitting I will try and add more stability limits and realistic generation load cases.
Focused views
Single-purpose maps for specific questions.
The master map above combines everything. The lighter-weight views below render the same underlying data for a single question. Use the arrows to step through them — click "Open interactive version" to launch the live tool for the current view.
