{
  "id": "vietnam_jetp_delayed_transmission",
  "version": "1.0",
  "status": "sensitivity_variant",
  "parent_scenario": "vietnam_jetp_transition",
  "variant_label": "Delayed Transmission",
  "variant_description": "North-South 500 kV Circuits 4+5 commission date slips two years (2030 \u2192 2032). Central region curtailment remains at 32% through the entire 2026-2030 mandate window. The 12 Mt abatement attributed to curtailment recovery drops out of the 2030 compliance stack \u2014 mandate ceiling breached.",
  "scenario_type": "Power Transition",
  "name": "Vietnam JETP \u2014 Delayed Transmission Variant",
  "subtitle": "Circuits 4+5 slip 2 years: Central region curtailment locked at 32% through 2030",
  "region_id": "vn",
  "tags": [
    "power-sector",
    "mandate",
    "transmission",
    "sensitivity",
    "jetp",
    "pdp8"
  ],
  "description": "Sensitivity variant on vietnam_jetp_transition: the North-South 500 kV transmission backbone (Circuits 4+5) is delayed two years \u2014 commissioning 2032 instead of 2030 \u2014 due to provincial land acquisition disputes in Quang Nam and Quang Ngai (42,000 affected households, compensation negotiations stall in 2027). Central region curtailment remains at 32% through the full 2026-2030 mandate window, preventing the 12 MtCO2 abatement that the base scenario attributes to curtailment recovery. Without the backbone, the mandate ceiling of 170 Mt is breached at ~181 Mt by 2030.",
  "baseline": {
    "year": 2026,
    "generation_fleet_gw": 84.5,
    "coal_gw": 26.0,
    "gas_ccgt_gw": 11.2,
    "hydro_gw": 22.5,
    "wind_gw": 6.8,
    "solar_gw": 16.5,
    "nuclear_gw": 0.0,
    "coal_capacity_factor": 0.58,
    "gas_capacity_factor": 0.52,
    "grid_carbon_intensity_g_per_kwh": 510,
    "annual_generation_twh": 310,
    "annual_emissions_mt_co2": 158,
    "peak_demand_gw": 51.0,
    "notes": "Identical to parent scenario vietnam_jetp_transition baseline. See parent for full fleet detail."
  },
  "target": {
    "reduction_pct": 17.9,
    "reduction_pct_basis": "bau_adjusted_2030",
    "deadline_year": 2030,
    "horizon_years": 4,
    "metric": "bau_adjusted_power_sector_co2_peak",
    "required_reduction_mt_co2": 37.0,
    "ceiling_mt_co2_by_2030": 170.0,
    "demand_growth_treatment": "growing_demand_adjusted",
    "demand_growth_cagr_pct": 9.4,
    "demand_by_2030_twh": 535
  },
  "projections": {
    "years": [
      2026,
      2027,
      2028,
      2029,
      2030
    ],
    "bau_mt_co2": [
      158,
      168,
      180,
      192,
      207
    ],
    "mandate_mt_co2": [
      158,
      165,
      170,
      176,
      181
    ],
    "ceiling_mt_co2": 170.0,
    "variant_notes": "Delayed transmission: 12 Mt curtailment-recovery abatement drops out of 2030 window. Base mandate path reached 169 Mt; this variant reaches ~181 Mt \u2014 11 Mt above the 170 Mt JETP ceiling. Solar + coal retirement + DSM abatement unchanged (33 Mt); only the transmission-enabled curtailment contribution (5 Mt from base by_2030 stack) and the transmission tech_vector abatement (12 Mt) are lost from the 2030 window."
  },
  "tech_vectors": [
    {
      "id": "offshore_wind_south_central",
      "label": "South Central Offshore Wind (Binh Thuan-Ba Ria)",
      "description": "Fixed-bottom offshore wind \u2014 same as parent scenario. 8.5yr lead time: first power 2034 at earliest under standard permitting. Unchanged by this variant.",
      "ce_model_mapping": "vietnam_offshore_wind_fixed",
      "mapping_fidelity": "direct",
      "constraints": {
        "permitting_timeline_yr": 8.0,
        "total_lead_time_yr": 8.5
      },
      "technical_parameters": {
        "target_nameplate_gw": 4.0,
        "capacity_factor": 0.5
      },
      "estimated_mt_co2": 8.8
    },
    {
      "id": "solar_plus_bess_central_highlands",
      "label": "Solar PV + BESS (Central Highlands Grid Unlock)",
      "description": "Utility-scale solar + BESS as in parent scenario. However, without North-South backbone, 32% curtailment persists through 2030. Effective generation after curtailment is roughly 77% of unconstrained output. The BESS still reduces curtailment by 18 ppts on co-located generation, but the regional grid absorption limit constrains total delivery.",
      "ce_model_mapping": "vietnam_utility_solar",
      "mapping_fidelity": "direct",
      "mapping_caveats": "In this delayed-transmission variant, curtailment remains at 32% through 2030 (vs 12% in base scenario). BESS co-location partially offsets (32%\u219214% for co-located plant) but the N-S backbone is the binding system constraint for total regional absorption.",
      "constraints": {
        "permitting_timeline_yr": 3.0,
        "total_lead_time_yr": 3.5,
        "curtailment_risk_without_transmission_pct": 32,
        "curtailment_reduction_with_bess_pct": 18,
        "effective_curtailment_2030_pct": 32
      },
      "technical_parameters": {
        "solar_target_gw": 8.0,
        "bess_target_gw": 3.2,
        "capacity_factor": 0.22
      },
      "estimated_mt_co2": 9.6
    },
    {
      "id": "coal_ammonia_cofiring",
      "label": "Coal Plant Ammonia Co-Firing (PPA Bridge)",
      "description": "Unchanged from parent scenario \u2014 cofiring proceeds at Vinh Tan 2/4, Duyen Hai 1/3 regardless of transmission timing.",
      "ce_model_mapping": "none (cofiring retrofit \u2014 no direct CE mapping)",
      "mapping_fidelity": "not_mapped",
      "constraints": {
        "permitting_timeline_yr": 2.0,
        "total_lead_time_yr": 2.5
      },
      "technical_parameters": {
        "eligible_coal_gw": 8.0,
        "cofiring_pct_by_heat": 20
      },
      "estimated_mt_co2": 6.4
    },
    {
      "id": "north_south_transmission_backbone",
      "label": "500 kV North-South Transmission Circuit 4+5 (DELAYED 2032)",
      "description": "SENSITIVITY CHANGE: Circuits 4+5 commission date slips from 2029\u20132030 to 2031\u20132032 due to provincial land acquisition disputes. 42,000 affected households in Quang Nam and Quang Ngai fail to reach compensation agreement by the 2026\u20132027 construction start target. Construction begins 2028; commissioning 2031\u20132032. Zero abatement contribution within the 2026\u20132030 mandate window.",
      "ce_model_mapping": "none (transmission infrastructure \u2014 enabling constraint, not abatement technology)",
      "mapping_fidelity": "not_mapped",
      "constraints": {
        "permitting_timeline_yr": 3.0,
        "total_lead_time_yr": 5.5,
        "commissioning_year_revised": 2032,
        "land_acquisition_delay_yr": 2.0,
        "variant_change": "total_lead_time increased from 3.5yr to 5.5yr (2yr land acquisition delay); commissioning 2032 instead of 2030"
      },
      "technical_parameters": {
        "new_circuits": 2,
        "circuit_length_km": 1800,
        "transfer_capacity_gw_added": 5.0,
        "capex_usd_b": 7.4
      },
      "estimated_mt_co2": 0.0,
      "variant_note": "Zero abatement in 2026-2030 mandate window. Base scenario attributed 12 Mt abatement to transmission-enabled curtailment recovery; this is the source of the ~12 Mt mandate miss in this variant."
    }
  ],
  "analysis": {
    "critical_path": "transmission_backbone_land_acquisition",
    "abatement_needed_mt_co2": 37.0,
    "estimated_total_mt_co2": 24.8,
    "by_2030_abatement_mt_co2": 26.0,
    "by_2030_abatement_note": "Without transmission: solar 9.6 Mt + coal retirement ~8.5 Mt + DSM ~4.5 Mt + cofiring 6.4 Mt = ~29 Mt (rounded to 26 Mt at 2030 window effective delivery). Mandate misses by ~11 Mt: BAU 207 - 26 Mt = 181 Mt > 170 Mt ceiling.",
    "mandate_outcome": "FAIL",
    "mandate_outcome_note": "Mandate ceiling breached: 181 Mt > 170 Mt JETP ceiling. Failure driven entirely by transmission delay \u2014 all other interventions proceed as planned but cannot deliver curtailment-recovery abatement without the N-S backbone.",
    "confidence": "medium",
    "confidence_rationale": "Land acquisition delay risk is well-documented in Vietnamese infrastructure projects. The 42,000 household ROW compensation in Quang Nam/Quang Ngai is the highest-risk land acquisition component. ADB/MoNRE oversight reduces but does not eliminate risk.",
    "sensitivity_delta_mt_co2": -12.0,
    "sensitivity_delta_note": "Base 2030 stack: 38 Mt. This variant: ~26 Mt. Delta: -12 Mt from transmission-enabled curtailment recovery dropping out of 2030 window. This is the single largest swing variable in the mandate scenario.",
    "tech_contributions": [
      {
        "label": "Utility solar PV + BESS (32% curtailment persists \u2014 base 20 Mt at 12%; at 32% effective ~15 Mt)",
        "mt_co2": 15.0,
        "delivery_window": "2028-2030",
        "contributes_to_2030_mandate": true
      },
      {
        "label": "Coal retirement/cancellation (8 GW early retirement + 4 GW cancelled \u2014 unchanged)",
        "mt_co2": 8.5,
        "delivery_window": "2027-2028",
        "contributes_to_2030_mandate": true
      },
      {
        "label": "Demand-side management (unchanged from base)",
        "mt_co2": 4.5,
        "delivery_window": "2027-2028",
        "contributes_to_2030_mandate": true
      },
      {
        "label": "Transmission-enabled curtailment recovery (DELAYED \u2014 zero contribution to 2030)",
        "mt_co2": 0.0,
        "delivery_window": "2032-2033",
        "contributes_to_2030_mandate": false
      }
    ]
  },
  "created": "2026-05-25",
  "last_updated": "2026-05-25",
  "author": "CE Scenario Engine v3.7 \u2014 sensitivity variant"
}