Scenario Inputs
Controls
Scenario settings
Scenario preset
Duration
Operating conditions
Moyle status
Generating units unavailable
Unit capacity assumptions Illustrative
Advanced system assumptions
Alternative import availability (EW + Greenlink)
Storage capacity assumption
Demand response assumption
Storage and demand response are reduced for longer events. These are screening assumptions, not operator dispatch instructions.
Result
Indicative system stress
Screening calculation
Severe
Indicative margin -510 MW (-7.5%)
Low
Elevated
High
Severe
≥12%5–12%0–5%<0%
Transparent calculation
Baseline vs selected scenario
| Input (illustrative MW) | Baseline | Selected | Change |
|---|---|---|---|
| Available domestic generation | 6,100 | 5,250 | -850 |
| Available net imports | 1,250 | 800 | -450 |
| of which Moyle | 450 | 0 | -450 |
| Assumed storage contribution | 120 | 120 | — |
| Assumed demand response | 120 | 120 | — |
| = Indicative available resources | 7,590 | 6,290 | -1,300 |
| − Illustrative demand | 6,800 | 6,800 | |
| = Indicative system margin | 790 | -510 |
What drove the change
- Moyle unavailable removes the assumed 450 MW net import contribution.
- 2 generating units unavailable removes 850 MW of assumed domestic generation.
- A 30-day event reduces sustained storage (120 MW) and demand response (120 MW) contributions.
- Winter peak with low wind assumes high demand and lower renewable output.
Illustrative screening calculation only. It does not model network deliverability, operator dispatch or reserve requirements and does not predict blackouts or load shedding.
Restoration sensitivity
Duration changes system and financial consequences
| Restoration assumption | System stress | Mutual Energy cash-flow | Downstream economic high |
|---|---|---|---|
| 24 hours | Severe | £4.72m | £127.3m |
| 7 days | Severe | £6.08m | £198.2m |
| 30 days | Severe | £11.3m | £269.7m |
Restoration periods are selected assumptions, not engineering forecasts. Mutual Energy and downstream values remain separate.
Comparison
All five presets under current conditions
| Preset | Resources | Margin | Stress | Economic high | Mutual Energy cash-flow |
|---|---|---|---|---|---|
| Baseline | 7,590 | 790 | Elevated | £47.8m | £0 |
| Moyle unavailable | 7,140 | 340 | Elevated | £47.8m | £11.3m |
| Two generating units unavailable | 6,740 | -60 | Severe | £269.7m | £0 |
| Compound failure | 6,290 | -510 | Severe | £269.7m | £11.3m |
| 30-day compound failure | 6,290 | -510 | Severe | £269.7m | £11.3m |
Model assumptions and limitations
Synthetic values
- All MW values (demand, generation, imports, storage, demand response) are synthetic round numbers chosen for illustration.
- Moyle, East-West and Greenlink import contributions are assumed peak net flows, not nameplate capacity.
- Generating unit sizes are editable illustrative values, not specific power stations.
- North Coast Foods Ltd is a fictional business; its profile is illustrative.
Simplified calculations
- Indicative available resources = domestic generation + net imports + storage + demand response.
- Indicative system margin = available resources − illustrative demand; stress bands: ≥12% Low, 5–12% Elevated, 0–5% High, <0% Severe.
- Storage and demand response contributions are scaled down for longer events using fixed factors.
- Business exposure uses additive scores from system stress and client profile inputs.
- Interruption episode lengths per stress level are illustrative and do not predict actual power cuts.
Not modelled
- Transmission and distribution network constraints and deliverability.
- Operator dispatch, market behaviour, reserve requirements and system stability (inertia, frequency).
- Interconnector flow direction, GB system conditions and North–South tie-line limits.
- Regional load shedding schemes, priority customers and restoration sequences.
- Fuel supply, weather variability and probability of the scenario occurring.
Why real information is needed
A real assessment requires verified site data, actual policy wording, operator information and engineering analysis. These outputs are for discussion only.