NC-METH-001 v1.1.0-revA — Part C: Per-Typology Specifications¶
T1 / T2 / T4A / T4B-DC / T6W / BESS — Identity, Geometry, Capacity, CAPEX, Yield, Offtaker, Suitability, Failure Modes¶
12 May 2026 · Internal · Author: AI-assisted, M. Forni review
⚠️ Revision note — what changed from v1.1.0¶
This revision (revA) supersedes Part C v1.1.0 issued earlier the same day. The substantive change:
v1.1.0 included a "methodology canonical" comparison column for per-typology CAPEX (T1 $645, T2 $820, T4A $950, T4B-DC $1,350, T6W $1,150). Those numbers were imported from the retracted Phase 3B desk bottom-up and are not sourced from any documented methodology artefact. The label "methodology canonical" was false.
The corrected position: - The LC v1.0 segment register per-typology unit costs are the only canonical CAPEX numbers (T1 $412, T2 $813, T4A $742, T4B-DC $700, T6W $732) - The memory's locked range "Solar $700–1,100/kWp (TOPCon 610Wp)" is the canonical range; T1 at $412 sits below this range and is flagged for engineering review priority - No per-typology methodology canonical CAPEX exists yet; building one is the AUDIT-040 / Annex H gap closed via WP2 + WP4
All other content in Part C v1.1.0 (typology identity, geometric constraints, capacity formulas, yield models, offtaker logic, suitability screens, failure modes, locked vs estate-specific parameters) is unchanged. The CAPEX section of each typology (C.X.4) is revised. Section C.7 cross-typology summary table needs no change (it never had the bad comparison column). Section C.8 acknowledged gaps is revised to state the Annex H gap correctly.
v1.1.0 is retracted; revA is canonical going forward.
C.0 Overview¶
Part C documents the six module types covered by the IEAT Solar methodology. Each subsection follows the same template:
- Physical and economic identity — what the typology IS, what it does, where deployed
- Geometric constraints — geometric filters from B.2 with explicit thresholds
- Capacity formula — kWp/m² coefficient and applicable adjustments
- CAPEX formula — LC v1.0 register canonical + memory range context + structural premium adjustments
- Yield model — estate-canonical P50 + typology-specific adjustments
- Offtaker logic — default attribution rule + edge cases
- Suitability screen — which estates this typology applies to and why
- Failure modes — what can go wrong; risk register input
- Locked vs estate-specific parameters — what's universal vs what tunes per estate
The six typologies are deliberately heterogeneous: T1–T2 are mature commercial-scale solar deployment patterns; T4A is parking infrastructure commercially proven globally; T4B-DC and T6W are LC-pioneered patterns where IEAT's industrial-estate context creates LC-specific deployment economics; BESS is the storage layer that pairs with several of the above.
Note on typology numbering: "T1 / T2 / T4A / T4B-DC / T6W" reflects historical development sequence at NewCo. T3 (industrial walkway), T5 (retired), and intermediate variants exist in historical artefacts but are not part of the canonical six. Reserve typologies (T1X / T2X / T6X) are addressed at the end of each parent typology's section.
Note on canonical CAPEX: Per the revision note above, the only documented canonical per-typology CAPEX is the LC v1.0 segment register. The memory-locked range is $700–1,100/kWp at TOPCon 610Wp; per-typology methodology canonical does not yet exist. Annex H (per AUDIT-040, delivered through WP2 + WP4 engineering review) will produce it.
C.1 T1 — Rooftop¶
C.1.1 Physical and economic identity¶
T1 is industrial and commercial rooftop PV: solar modules mounted on the roof of an existing IEAT-owned admin building, IEAT-owned factory building, or tenant-owned building with consent. The roof acts as the structural support; ballast or penetration-anchored racking sits on the roof; modules cable down to a string inverter, then to a roof-edge AC busbar or directly to the building's MV switchgear for self-consumption.
T1 is the lowest-CAPEX typology in the family per kWp at LC. The economic advantage at LC comes from three sources: (a) zero foundation work (the roof IS the foundation); (b) no land cost or site preparation; © shortest cable runs to point of consumption (most BTM-friendly). Trade-off: smallest per-segment capacity (typical 100–300 kWp per building), highest tenant-coordination burden, structural integrity uncertainty until ROOF-001 assessment closes.
LC has 12 T1 segments totalling 2.15 MWp / $0.89M (6% of envelope by MWp; 4% by CAPEX). Eleven are IEAT-direct (admin buildings); one is tenant-attributed (Sankyu LC-T1-10).
C.1.2 Geometric constraints¶
- Roof area: > 500 m² minimum
- Roof type: flat or low-slope (< 5° pitch); pitched > 25° excluded
- Building age: < 30 years (ACM presence risk in older industrial buildings)
- Ownership: IEAT-owned admin or factory OR tenant-owned with consent
- Roof access: stair or ladder access available; crane access feasible for installation
- Roof penetrations: HVAC, exhaust, water tanks, antennas navigable
C.1.3 Capacity formula¶
Capacity = roof area × layout efficiency × module density
- Module density: 254 W/m² nameplate (TOPCon 610Wp on 2.4 m²)
- Layout efficiency: 50–60% for flat rooftops (after setbacks + obstructions + access)
- Effective deployable density: 130–160 W/m²
For a typical 1,000 m² industrial rooftop: ~140 kWp.
C.1.4 CAPEX formula¶
CAPEX = kWp × unit cost
- LC v1.0 unit cost (canonical): $412/kWp
- Memory-locked canonical range (
Solar $700–1,100/kWpper memory edit 16, TOPCon 610Wp basis): $700–1,100/kWp - ⚠ T1 at LC sits below the memory canonical range. Three possibilities: (a) genuine LC-specific advantage (zero-foundation rooftop installation on existing IEAT admin buildings; small per-segment scale; shortest cable runs); (b) systematic understatement in LC v1.0 register; © the memory range is a project-blend rate that doesn't represent the floor for the simplest typology. T1 unit cost is the highest-priority engineering review item in WP2 — confirm $412 is achievable or revise.
- Per-typology methodology canonical: not yet documented; AUDIT-040 / Annex H gap. WP2 + WP4 produce it via engineering review.
- Premium adjustments:
- C4 corrosion premium for coastal estates: +10–15% for marine-grade BOS components [AUDIT-002 verification pending WP4]
- ACM remediation premium for buildings flagged: +$15–25K per building (separate work scope, not in $/kWp)
- Roof reinforcement premium where structural capacity marginal: +$30–80K per building if ROOF-001 requires beam upgrades
C.1.5 Yield model¶
- Estate-canonical P50: estate's RES-001 number (LC 1,485 methodology / 1,380 model — pending WP1)
- Rooftop-specific adjustment: −3% to −5% for low-tilt rooftop installations in tropics
- Bifacial uplift: 0% (rooftop reflective surface low)
- Soiling: per estate canonical; rooftop slightly better than ground (less dust)
- Y1 effective P50 for LC T1: 1,330–1,410 kWh/kWp/yr (rooftop-adjusted from estate canonical)
C.1.6 Offtaker logic¶
Per B.6: - IEAT-owned admin building → IEAT-direct (LC default; 11 of 12 LC T1 segments) - IEAT-owned factory with single tenant → IEAT-direct by default - Tenant-owned building → tenant-direct ESA required (LC: LC-T1-10 Sankyu, 0.65 MWp)
C.1.7 Suitability screen¶
| Estate | Suitability | Notes |
|---|---|---|
| LC | HIGH | 12 segs / 2.15 MWp; IEAT admin + factory coverage strong |
| BP | HIGH | Similar admin + factory profile; larger contiguous footprint |
| MTP | HIGH | Massive admin + petrochemical factory rooftops |
| MTP Port | MEDIUM | Mixed industrial; some marine-corrosion concerns |
| Bangplee | MEDIUM | Land-lease estate; tenants own buildings; consent-heavy |
| Lat Krabang | MEDIUM | Land-lease estate; similar to Bangplee |
| Lamphun | LOW | Land-lease estate; smaller building footprint |
| Smart Park | MEDIUM | Newer development; admin building only |
| Songkhla | MEDIUM | Coastal corrosion; mature tenant base |
| Songkhla-S | MEDIUM | Similar to Songkhla |
| Phichit | LOW | Northern; smaller industrial footprint |
| Sa Kaeo | LOW | Eastern; smaller building footprint |
| Bang Chan | LOW | Older estate; building age concerns |
| Kaeng Khoi | MEDIUM | Newer EEC-adjacent |
| Nakhon Luang | MEDIUM | Mixed |
C.1.8 Failure modes¶
- Roof age and condition uncertainty until ROOF-001 + ACM screening
- Roof age > 30 years excludes building entirely
- ACM remediation required in 1990s-and-earlier industrial roofs; 12–24 week delay
- Structural capacity marginal: reinforcement required or T1 segment dropped
- Penetration leaks: ballast-anchored preferred
- Tenant consent withdrawal (tenant-attributed T1) — small replacement reserve (T1X)
- Rooftop equipment changes during operations period
C.1.9 Locked vs estate-specific parameters¶
| Parameter | Status | Value / range |
|---|---|---|
| Module: TOPCon 610Wp | LOCKED | per memory edit 16 |
| Roof perimeter setback | LOCKED | 1.0 m |
| Roof equipment setback | LOCKED | 0.5 m |
| Roof access hatch setback | LOCKED | 2.0 m |
| Layout efficiency | ESTATE-SPECIFIC | 50–60% based on building density and obstructions |
| Unit cost ($/kWp) | ESTATE-SPECIFIC (canonical TBD) | LC v1.0 $412; methodology canonical pending Annex H |
| Building age limit | LOCKED | 30 years |
| Pitch limit | LOCKED | < 5° flat / low-slope |
| Roof reinforcement premium | ESTATE-SPECIFIC | per ROOF-001 outcome |
| Tenant ESA premium | ESTATE-SPECIFIC | tenant-direct vs IEAT-direct margin |
C.1.10 T1X reserve typology¶
T1X (building extension) is the aspirational reserve: rooftop extensions on existing IEAT buildings. LC's T1X reserve is 0.5 MWp / $0.21M. Same parameters as T1 with confidence < 0.20; promoted into active envelope only after Phase 0B owner confirmation and structural assessment.
C.2 T2 — Ground-mount¶
C.2.1 Physical and economic identity¶
T2 is utility-style ground-mount PV: modules on fixed-tilt or single-axis tracker structures on unused parcels, buffer strips, or easement land within the IEAT estate boundary. Foundations are typically shallow piles into compacted soil; modules tilt at ~10–15° in the tropics; row spacing managed for shading minimisation and access.
T2's economic profile is mid-range: higher CAPEX than T1 (foundations + site prep) but larger per-segment capacity (typical 200 kWp–2 MWp per parcel) and standardised installation (T2 is the global commercial-scale solar default). Land cost is zero within IEAT concession; site preparation modest.
LC has 7 T2 segments totalling 4.35 MWp / $3.54M (13% of envelope by MWp; 14% by CAPEX). Six are IEAT-direct buffer parcels; one is tenant-attributed (LC-T2-07 Michelin, 0.45 MWp).
C.2.2 Geometric constraints¶
- Parcel area: > 1,000 m² minimum
- Unbuilt status: per satellite imagery + IEAT cadastral
- Easement-free: no utility easements conflicting with module rows
- Buffer-strip eligibility: where parcel is a buffer strip, IEAT must confirm availability
- Boundary setbacks: 5 m from estate boundary, IEAT-determined fire lanes, drainage easements
- Soil quality: bearable load capacity for pile foundations (> 50 kPa); avoid contaminated soils
C.2.3 Capacity formula¶
Capacity = parcel area × layout efficiency × module density
- Module density: 254 W/m² nameplate
- Layout efficiency: 40–55% for ground-mount
- Effective deployable density: 100–130 W/m²
For a typical 5,000 m² buffer parcel: ~575 kWp.
C.2.4 CAPEX formula¶
CAPEX = kWp × unit cost
- LC v1.0 unit cost (canonical): $813/kWp
- Memory-locked canonical range: $700–1,100/kWp
- T2 at LC sits comfortably within the canonical range. LC's $813 is mid-range — consistent with mature commercial-scale ground-mount economics.
- Per-typology methodology canonical: not yet documented; AUDIT-040 / Annex H gap. T2 is the lowest-priority typology for Annex H given LC value is within memory range.
- Build composition: ~50% modules + ~20% inverters + ~20% structural + ~10% civil
- Premium adjustments:
- C4 corrosion premium for coastal estates: +10–15%
- Soil contamination remediation: +$50–150K per parcel if remediation required
- Drainage / grading premium for sloped parcels: +5–10%
- Substation extension if parcel far from existing MV switchgear: +$50–200K per parcel
C.2.5 Yield model¶
- Estate-canonical P50: estate's RES-001 number
- Ground-mount adjustment: 0% (this IS the optimal-tilt baseline)
- Bifacial uplift: +5–7% if light-coloured ground (gravel, white-rock) — small at LC where parcels typically grassy
- Soiling: standard estate canonical
- Y1 effective P50 for LC T2: 1,380 (model) or 1,485 (methodology) per AUDIT-001 reconciliation
C.2.6 Offtaker logic¶
- IEAT-retained buffer parcels → IEAT-direct (LC: 6 of 7 T2 segments)
- Tenant-adjacent parcels with shared use → tenant-attributed (LC: LC-T2-07 Michelin)
- Tenant-leased parcels with tenant-direct ESA → tenant-direct (rare in current LC inventory)
C.2.7 Suitability screen¶
| Estate | Suitability | Notes |
|---|---|---|
| LC | MEDIUM | 7 segs / 4.35 MWp; smaller buffer parcels scattered |
| BP | HIGH | Large contiguous buffer parcels available |
| MTP | HIGH | Massive estate; ample buffer land |
| MTP Port | MEDIUM | Port operations constrain |
| Bangplee | LOW | Land-lease; limited IEAT-retained |
| Lat Krabang | LOW | Land-lease; limited IEAT-retained |
| Lamphun | MEDIUM | Buffer parcels available |
| Smart Park | MEDIUM | Newer; planned buffer strips |
| Songkhla | MEDIUM | Coastal |
| Songkhla-S+Rubber City | HIGH | Large estate |
| Phichit | HIGH | Smaller building density; more ground |
| Sa Kaeo | HIGH | Eastern, ample land |
| Bang Chan | LOW | Older estate, scarce buffer |
| Kaeng Khoi | MEDIUM | Newer |
| Nakhon Luang | MEDIUM | Mixed |
C.2.8 Failure modes¶
- Parcel boundary disputes — RTK GPS survey required (Phase 0B); IEAT cadastral may not match operational reality
- Soil contamination from prior industrial use — heavy metals, hydrocarbons; remediation expensive
- Drainage and flood-zone issues — particularly at coastal estates
- Setback rules in conflict with parcel size — small parcels may lose 20–30% effective area
- Soil bearing capacity inadequate — pile foundations need rework; cost premium 10–20%
- MV grid connection distance — far parcels need substation extension
C.2.9 Locked vs estate-specific parameters¶
| Parameter | Status | Value / range |
|---|---|---|
| Module: TOPCon 610Wp | LOCKED | |
| Row spacing | LOCKED | 2–3 module-heights (fence-to-fence) |
| Boundary setback | LOCKED | 5 m |
| Layout efficiency | ESTATE-SPECIFIC | 40–55% |
| Unit cost ($/kWp) | ESTATE-SPECIFIC (canonical TBD) | LC v1.0 $813; methodology canonical pending Annex H |
| Soil remediation premium | ESTATE-SPECIFIC | per Phase 0B soil assessment |
| Tilt angle | ESTATE-SPECIFIC | 10–15° tropic; lower for shaded sites |
| Tracker vs fixed | ESTATE-SPECIFIC | fixed-tilt default; tracker if parcel >10 MWp |
C.2.10 T2X reserve typology¶
T2X (vacant buffer parcels) is the aspirational reserve below 0.20 confidence floor. LC's T2X reserve is 1.5 MWp / $1.22M. Phase 0A IEAT cadastral validation required for promotion.
C.3 T4A — Carport¶
C.3.1 Physical and economic identity¶
T4A is parking-lot canopy PV: solar modules on drilled-pier-supported steel canopy structures over passenger and light commercial parking. The canopy delivers shade (high tenant value) + generates solar (high investment value). Canopy spans 10–20 m clear width with 3.0 m soffit clearance.
T4A has the highest single-segment capacity in the family (LC's LC-T4A-01 is 2.88 MWp) because parking lots are large and contiguous. Economic profile: medium-high CAPEX (structural premium for canopy steel) offset by good kWp/m² density and dual-use value. Best-deployed on existing IEAT parking infrastructure where IEAT itself is offtaker.
LC has 7 T4A segments totalling 11.35 MWp / $8.42M (33% of envelope by MWp; 34% by CAPEX). All are IEAT-direct.
C.3.2 Geometric constraints¶
- Parking width: 10/15/20 m standard spans
- Clear soffit: 3.0 m clearance possible
- Lot size: > 2,000 m²
- Parking lot polygon: continuous, parking-only zone
- Drainage: existing drainage adequate or upgradeable
- Drilled-pier feasibility: subsurface conditions support 2–4 m drilled piers
C.3.3 Capacity formula¶
Capacity = parking area × layout efficiency × module density
- Module density: 254 W/m² nameplate
- Layout efficiency: 40–50% for carport
- Effective deployable density: 105–125 W/m²
For LC-T4A-01 (the largest LC segment): ~125 W/m² × ~23,000 m² = 2.88 MWp ✓ matches register.
C.3.4 CAPEX formula¶
CAPEX = kWp × unit cost
- LC v1.0 unit cost (canonical): $742/kWp
- Memory-locked canonical range: $700–1,100/kWp
- T4A at LC sits at the lower bound of the canonical range. Plausibly LC-specific advantages: 3.0 m soffit (standard parking, not low-clearance industrial); drilled-pier feasibility (paved compacted fill); IEAT-direct (no tenant negotiation premium); single-mobilisation procurement; standardised steel design. WP2 engineering review confirms or revises.
- Per-typology methodology canonical: not yet documented; AUDIT-040 / Annex H gap. WP4 produces it.
- Build composition: ~35% modules + ~30% structural steel + ~15% drilled piers + ~10% electrical + ~10% civil
- Premium adjustments:
- C4 corrosion premium for coastal estates: +10–15% for marine-grade steel
- Drilled-pier geotechnical fail (rock layer or contaminated fill): +10–25% for alternate foundation
- Lighting and EV charging integration: +$30–80K per segment (not in $/kWp)
- Canopy aesthetic premium (tenant request, paint, branding): +5–8%
C.3.5 Yield model¶
- Estate-canonical P50: estate's RES-001 number
- Carport-specific adjustment: −1% to −2% for shading from light poles, signage
- Bifacial uplift: +4–6% (parking asphalt has moderate albedo)
- Soiling: similar to ground-mount; slightly worse if parking dust from vehicle traffic
- Y1 effective P50 for LC T4A: ~1,400–1,510 kWh/kWp/yr
C.3.6 Offtaker logic¶
- All IEAT parking infrastructure → IEAT-direct (LC: all 7 T4A segments)
- Tenant-private parking (rare in IEAT estates) → tenant-direct ESA (sub-typology T4A-tenant)
C.3.7 Suitability screen¶
| Estate | Suitability | Notes |
|---|---|---|
| LC | HIGH | 7 segs / 11.35 MWp; LC-T4A-01 flagship at 2.88 MWp |
| BP | HIGH | Comparable scale to LC |
| BP-S | MEDIUM | Smaller parking footprint |
| MTP | MEDIUM | Industrial parking sparse vs admin |
| MTP Port | LOW | Port operations limit parking |
| Bangplee | LOW | Tenant-owned parking |
| Lat Krabang | LOW | Tenant-owned parking |
| Lamphun | LOW | Limited parking footprint |
| Smart Park | MEDIUM | Newer; planned parking |
| Songkhla | MEDIUM | Coastal corrosion concern |
| Songkhla-S | MEDIUM | Similar |
| Phichit | LOW | Small footprint |
| Sa Kaeo | LOW | Small footprint |
| Bang Chan | LOW | Older estate |
| Kaeng Khoi | MEDIUM | Newer EEC-adjacent |
| Nakhon Luang | MEDIUM | Mixed |
C.3.8 Failure modes¶
- Drilled-pier geotechnical fail — rock layer, contaminated fill, or unstable soils require alternate foundation; cost +10–25%
- Parking flow disruption during construction — IEAT and tenants need maintained parking access; phased construction adds 4–8 weeks
- Canopy span design failure — wind loading, seismic considerations; span >20 m typically excluded
- Rain runoff management — canopy drainage must integrate with existing parking drainage
- EV charging integration scope creep
- Tenant aesthetic objections at flagship admin areas
C.3.9 Locked vs estate-specific parameters¶
| Parameter | Status | Value / range |
|---|---|---|
| Module: TOPCon 610Wp | LOCKED | |
| Soffit clearance | LOCKED | 3.0 m |
| Pedestrian setback | LOCKED | 0.5 m |
| Parking width spans | LOCKED | 10 / 15 / 20 m standard |
| Layout efficiency | ESTATE-SPECIFIC | 40–50% |
| Unit cost ($/kWp) | ESTATE-SPECIFIC (canonical TBD) | LC v1.0 $742; methodology canonical pending Annex H |
| Drilled-pier depth | ESTATE-SPECIFIC | 2–4 m typical |
| C4 corrosion premium | ESTATE-SPECIFIC | coastal vs inland |
| Lighting/EV integration | ESTATE-SPECIFIC | optional scope |
C.4 T4B-DC — Arterial canopy (dual N/S)¶
C.4.1 Physical and economic identity¶
T4B-DC is arterial-road canopy PV with dual North/South orientation: modules mounted on a canopy spanning an internal road or arterial, with one face tilted North and the other tilted South. The dual orientation captures both AM (East-leaning South-face) and PM (West-leaning North-face) sun, maximising daily generation over a single-orientation canopy.
T4B-DC is LC-pioneered in the IEAT context. Most published utility carport designs use single-axis tilt. The dual-orientation pattern works because IEAT's internal road geometry is typically arterials running East-West, making North/South canopy orientation natural. Single-mobilisation deployment is the LC cost advantage.
LC has 16 T4B-DC segments totalling 1.83 MWp / $1.28M (5% of envelope by MWp; 5% by CAPEX). Eight are IEAT-side (West-side, IEAT-direct); eight are tenant-side (East-side, tenant-attributed).
C.4.2 Geometric constraints¶
- Carriageway width: 6–9 m
- Length: > 100 m
- No overhead utilities: no overhead electric, telecom, or gas lines crossing the road
- Bridge clearance: 5.0–6.0 m preserved
- Pedestrian/cyclist provisions: side pathways preserved
- Drainage: canopy drainage integrated with existing stormwater management
C.4.3 Capacity formula¶
Capacity = canopy area × layout efficiency × module density
- Module density: 254 W/m² nameplate
- Layout efficiency: 45–55% for dual N/S canopy
- Effective deployable density: 110–135 W/m²
For a typical 1,000 m² T4B-DC segment: ~125 kWp.
C.4.4 CAPEX formula¶
CAPEX = kWp × unit cost
- LC v1.0 unit cost (canonical): $700/kWp (single-mobilisation conditional)
- Memory-locked canonical range: $700–1,100/kWp
- T4B-DC at LC sits at the lower bound of the canonical range. The LC $700 number is conditional on single-mobilisation procurement (whole arterial in one EPC contract). If procurement forces phased deployment, the +25% premium applies and T4B-DC moves into the mid-range. WP4 documents the single-mob vs phased decision per estate.
- Per-typology methodology canonical: not yet documented; AUDIT-040 / Annex H gap. T4B-DC is LC-pioneered, so the methodology canonical when built will inherit heavily from LC's deployment.
- Phased deployment premium: +25% (i.e., $875/kWp) if procurement forces phased construction
- Premium adjustments:
- C4 corrosion premium for coastal estates: +10–15%
- Overhead utility relocation premium: +$20–80K per segment (not in $/kWp)
- Traffic management premium: +$10–30K per segment (signage, flagmen during construction)
C.4.5 Yield model¶
- Estate-canonical P50: estate's RES-001 number
- T4B-DC adjustment: +1% to +3% (dual N/S captures more daily sky than single-orientation)
- Bifacial uplift: +4–6% (high albedo from road surface)
- Soiling: typical estate canonical; slightly worse if dust from road traffic
- Y1 effective P50 for LC T4B-DC: ~1,420–1,540 kWh/kWp/yr
C.4.6 Offtaker logic¶
Per B.6, per-side rule: - IEAT internal road (West-side) → IEAT-direct (LC: 8 of 16 segments) - Tenant-adjacent arterial (East-side) → tenant-attributed per side (LC: 8 segments; 5 named anchors + 3 mixed/inferred)
C.4.7 Suitability screen¶
| Estate | Suitability | Notes |
|---|---|---|
| LC | HIGH | 16 segs / 1.83 MWp; rich internal road network |
| BP | HIGH | Similar internal road profile |
| Lat Krabang | MEDIUM | Land-lease but some IEAT-owned arterials |
| MTP | HIGH | Massive arterial network |
| MTP Port | MEDIUM | Port-internal arterials |
| Songkhla | MEDIUM | Mature road network |
| Other estates | LOW–MEDIUM | Smaller arterial networks |
C.4.8 Failure modes¶
- Phased vs single-mobilisation procurement — if EPC procurement forces phased, unit cost rises 25%; segment economics degrade
- EPC procurement for arterial work — Thai EPC market may not have arterial-canopy-specialist firms
- Traffic disruption during construction — internal road closures 4–8 weeks per arterial
- Overhead utility relocation — some IEAT arterials have overhead electric or telecom
- Tenant consent on tenant-side arterials
- Drainage conflicts
C.4.9 Locked vs estate-specific parameters¶
| Parameter | Status | Value / range |
|---|---|---|
| Module: TOPCon 610Wp | LOCKED | |
| Dual N/S configuration | LOCKED | per LC methodology pioneering |
| Carriageway edge setback | LOCKED | 0.5 m |
| Bridge clearance | LOCKED | 5.0–6.0 m preserved |
| Single-mobilisation procurement assumption | ESTATE-SPECIFIC | LC committed; BP TBD |
| Unit cost ($/kWp) | ESTATE-SPECIFIC (canonical TBD) | LC v1.0 $700 single-mob; methodology canonical pending Annex H |
| Layout efficiency | ESTATE-SPECIFIC | 45–55% |
| Carriageway width range | LOCKED | 6–9 m |
| Phased deployment premium | LOCKED | +25% |
C.5 T6W — Wide canal canopy¶
C.5.1 Physical and economic identity¶
T6W is wide canal canopy PV: modules on fixed-portal-frame steel structures anchored to concrete-lined canal banks, spanning the canal. Frame portals at intervals (8–12 m apart) carry the modules at ~4–5 m above water level. Modules orient North-South across the canal width.
T6W is LC-pioneered in scale. Floating PV exists globally but canal-canopy (fixed structure, not floating) is LC-specific. The economic advantage is unique site availability (water surface that's not otherwise used) and low foundation cost (concrete-lined banks already exist as load-bearing). Trade-off: canopy structural complexity, biofouling and bird-management costs, water-level variation tolerance.
LC has 5 T6W segments totalling 14.91 MWp / $10.91M (43% of envelope by MWp; 44% by CAPEX). All five are tenant-attributed; three to Thai Summit Group (the concentration constraint).
C.5.2 Geometric constraints¶
- Water width: > 15 m clear
- Concrete-lined banks: load-bearing for portal foundations; soft/earthen banks excluded
- Length: > 200 m
- Bridge-free run: > 50 m between bridges
- Water depth: 1.0–5.0 m typical; bathymetric survey verifies bottom conditions
- Boat traffic: light or none
- Pedestrian access: maintained at intervals (~100–200 m gaps)
- Bird-management consideration: methodology requires bird deterrent strategy
C.5.3 Capacity formula¶
Capacity = canal area × layout efficiency × module density
- Module density: 254 W/m² nameplate
- Layout efficiency: 45–55% for canal canopy
- Effective deployable density: 110–130 W/m²
For LC-T6W-01 (largest LC T6W): ~120 W/m² × ~35,000 m² = 4.20 MWp ✓ matches register.
C.5.4 CAPEX formula¶
CAPEX = kWp × unit cost
- LC v1.0 unit cost (canonical): $732/kWp
- Memory-locked canonical range: $700–1,100/kWp
- T6W at LC sits at the lower bound of the canonical range. Plausibly LC-specific advantages: concrete-lined canal banks (load-bearing foundations exist); fixed-portal-frame standardised; IEAT canal corridors planned and accessible; portal spacing 8–12 m proven. Trade-off: T6W carries operational premiums (biofouling, bird-management, marine-grade if coastal) that don't show in $/kWp but DO show in OPEX. WP2 engineering review validates the LC CAPEX position.
- Per-typology methodology canonical: not yet documented; AUDIT-040 / Annex H gap. T6W is LC-pioneered at scale, so the methodology canonical will inherit heavily from LC's deployment.
- Build composition: ~30% modules + ~30% portal-frame steel + ~15% bank-anchored foundations + ~15% electrical + ~10% biofouling/bird management
- Premium adjustments:
- C4 corrosion premium for coastal-canal estates (LC, MTP Port): +15–20% (saltwater + humidity)
- Bathymetric / dredging premium if canal bottom needs preparation: +5–10%
- Bird deterrent system: +$15–30K per segment
- Anti-soiling coatings: +\(0.5–1.0/kWp** (capex) + **+\)0.3/kWp/yr (opex)
- Marine-grade vs standard steel: +10–15%
C.5.5 Yield model¶
- Estate-canonical P50: estate's RES-001 number
- T6W canopy adjustment: −1% to −2% (humidity from water; biofouling cumulative over 25 years)
- Bifacial uplift: +1–2% (water albedo is moderate but variable)
- Soiling: estate canonical, plus +1–3% biofouling allowance; requires monthly cleaning vs quarterly elsewhere
- Y1 effective P50 for LC T6W: ~1,370–1,470 kWh/kWp/yr
C.5.6 Offtaker logic¶
Per B.6: - Adjacent to tenant operations → tenant-attributed default (LC: all 5 T6W segments) - LC-T6W-03 LC2 Power Plant special case: power-producer offtaker ESA sub-class — methodology should formalise this sub-class - Multi-tenant clusters: Thai Summit Group (LC-T6W-01, -02 = 7.85 MWp / $5.74M, 22% of LC envelope, single-group concentration)
C.5.7 Suitability screen¶
| Estate | Suitability | Notes |
|---|---|---|
| LC | HIGH | 5 segs / 14.91 MWp; canal network well-suited |
| BP | HIGH | Similar canal network (subject to confirmation) |
| MTP | MEDIUM | Limited internal canals; mostly port |
| MTP Port | MEDIUM | Port canals + drainage |
| Other estates | LOW | Smaller or absent canal networks |
C.5.8 Failure modes¶
- Bank stability — bathymetric + bank-soundness survey required (Phase 0B)
- Seasonal water-level variation — flood season vs dry season; canopy clearance must accommodate
- Biofouling on submerged or wave-splash components
- Bird/wildlife management — bird droppings on modules; ongoing opex
- Boat traffic — even occasional navigation requires bridge gates or canopy elevation
- Tenant consent withdrawal — Thai Summit Group concentration; T6X reserve is small (1.5 MWp / $1.10M); not sufficient to cover Thai Summit cluster refusal
- LC2 Power Plant special case — power-producer offtaker ESA structure unique; legal opinion required before scale-up
C.5.9 Locked vs estate-specific parameters¶
| Parameter | Status | Value / range |
|---|---|---|
| Module: TOPCon 610Wp | LOCKED | |
| Bank edge setback | LOCKED | 0.5 m |
| Water width minimum | LOCKED | 15 m clear |
| Length minimum | LOCKED | 200 m |
| Bridge-free run minimum | LOCKED | 50 m |
| Portal frame structure | LOCKED | fixed (not floating) |
| Concrete-lined banks requirement | LOCKED | load-bearing requirement |
| Pedestrian access intervals | LOCKED | every 100–200 m |
| Unit cost ($/kWp) | ESTATE-SPECIFIC (canonical TBD) | LC v1.0 $732; methodology canonical pending Annex H |
| C4 corrosion premium | ESTATE-SPECIFIC | coastal-canal estates |
| Biofouling cleaning frequency | LOCKED | monthly (vs quarterly elsewhere) |
| Bird deterrent strategy | ESTATE-SPECIFIC | per site |
C.5.10 T6X reserve typology¶
T6X (drainage canal extension) is the aspirational reserve below 0.20 floor. LC's T6X reserve is 1.5 MWp / $1.10M. Phase 0B RTK GPS canal survey required for promotion.
C.6 BESS — Battery storage¶
C.6.1 Physical and economic identity¶
BESS (Battery Energy Storage System) is containerised lithium iron phosphate (LFP) storage paired with PV deployments. The methodology uses 5 MWh containers as the standard unit (40-ft ISO container with battery modules, BMS, inverters, fire suppression, HVAC for thermal management). Multi-container clusters at large sites.
BESS economics differ from PV. Revenue stack: - Curtailment recovery — store excess PV that would otherwise be curtailed - Demand charge management — shave evening demand peaks at host facility - Time-shift — discharge during higher-tariff periods (TOU peak hours) - Frequency regulation / ancillary services — rare in Thailand utility market; not currently modeled
LC is no-BESS by design per IC paper §1. BP and other EEC estates use BESS where curtailment risk or demand charge structure justifies.
C.6.2 Geometric constraints¶
- Site area: ~50 m² per 5 MWh container
- Adjacency: PV lot for curtailment-recovery sizing; load centre for demand-charge management
- Access: service vehicle access
- HVAC and ventilation: thermal management infrastructure
- Interconnect at PCC: point of common coupling to MV switchgear
- Fire / safety setbacks: per Thai fire code (5 m from buildings, 3 m between containers)
C.6.3 Capacity formula¶
BESS sizing is decision-driven, not geometry-driven:
- Curtailment recovery: size to capture top 10–20% of PV generation peaks
- Demand charge management: size to shave peak demand × 2 hours (typical Thai industrial 16:00–19:00 peak window)
- Time-shift: size depends on TOU spread
Typical estate sizing: 0.05–0.20 MWh per MWp PV (so 5–6 MWh BESS for 30–40 MWp PV; matches BP memory reference).
C.6.4 CAPEX formula¶
CAPEX = MWh × unit cost (LFP)
- LFP container cost (canonical): $175/kWh (April 2026 update; replaces older $400/kWh per memory edit 16)
- Thermal management premium: +\(10–15/kWh** (HVAC, fire suppression, monitoring) — total **\)185–190/kWh all-in
- Soft costs (commissioning, grid interconnect, EMS integration): +5–10% on hardware
- Mid-life replacement at Y12: $80–120/kWh (per BNEF cost-curve trajectory; replace cells, retain container/HVAC/inverters)
Note: BESS unit cost basis is $/kWh, not \(/kWp. Direct comparison to the solar memory range (\)700–1,100/kWp) is not meaningful for BESS.
For LC's hypothetical 5.5 MWh BESS (LC is no-BESS in v1.0, but as illustration): 5,500 kWh × $185 + 7% soft costs = $1.09M.
C.6.5 "Yield" model — throughput, not yield¶
- Round-trip efficiency: 88–92% (LFP standard; 90% canonical)
- Cycle life: 6,000–8,000 cycles at 80% depth-of-discharge (DOD)
- Calendar life: 12–15 years before significant degradation
- Annual throughput: depends on dispatch strategy (typical industrial 250–350 cycles/year)
- Degradation curve: ~3% per year initial; mid-life replacement Y12 at ~70% original capacity
C.6.6 Offtaker logic¶
- Sited at IEAT load centre → IEAT-direct (IEAT pays for demand charge service)
- Sited at tenant load centre → tenant-attributed
- Curtailment recovery → revenue accrues to PV offtaker
C.6.7 Suitability screen¶
| Estate | Suitability | Notes |
|---|---|---|
| LC | NO | Design choice: BTM only, no curtailment, no demand-charge sufficient to justify |
| BP | YES | Demand-charge management + carbon revenue context |
| Bangplee | YES | BESS at tenant load centres |
| Lat Krabang | YES | Similar to Bangplee |
| MTP | YES | Massive load profile |
| MTP Port | YES | Port operations have peak demand spikes |
| Songkhla | MAYBE | Coastal climate considerations |
| Other estates | MAYBE | Per estate-specific analysis |
C.6.8 Failure modes¶
- Cell degradation faster than nameplate
- Thermal events (LFP safest chemistry but not zero-risk)
- Mid-life replacement cost trajectory
- Demand charge structure changes
- Curtailment estimate vs actual behaviour
- LFP cost curve divergence from BNEF forecast
- Container thermal management failure in Thai heat
C.6.9 Locked vs estate-specific parameters¶
| Parameter | Status | Value / range |
|---|---|---|
| Chemistry: LFP | LOCKED | (no NMC, no Lead-Acid for stationary) |
| Container size: 5 MWh | LOCKED | (40-ft ISO standard) |
| Round-trip efficiency | LOCKED | 88–92% |
| Cycle life: 6,000–8,000 | LOCKED | at 80% DOD |
| Calendar life | LOCKED | 12–15 years; mid-life replacement Y12 |
| Unit cost: $175/kWh | ESTATE-SPECIFIC | + thermal premium $10–15/kWh |
| Sizing (MWh per MWp PV) | ESTATE-SPECIFIC | 0.05–0.20 |
| Revenue stack composition | ESTATE-SPECIFIC | curtailment / demand charge / time-shift weighting |
| Mid-life replacement cost | ESTATE-SPECIFIC | BNEF curve; refresh annually |
| Discharge duration | ESTATE-SPECIFIC | 1-hr or 2-hr standard |
| Fire / safety setback | LOCKED | per Thai fire code |
C.6.10 BESS as a cross-typology layer¶
Unlike T1–T6W (which are spatial typologies occupying distinct surfaces), BESS is a temporal/functional layer that pairs with PV. The methodology treats BESS as the 6th typology for procurement and modeling consistency, but the underlying analytical structure is different: BESS is sized per estate's revenue stack composition, not per-segment.
Cross-references: - BESS interacts with B.4 yield (curtailment recovery depends on PV generation profile) - BESS interacts with B.6 offtaker attribution (demand-charge revenue accrues to load owner) - BESS interacts with Part D financial modelling (cycle dispatch, mid-life replacement, demand-charge revenue)
C.7 Cross-typology summary table¶
| Typology | LC segs | LC MWp | LC CAPEX | LC v1.0 $/kWp (canonical) | vs memory range ($700–1,100) | Confidence (LC) | Offtaker default |
|---|---|---|---|---|---|---|---|
| T1 rooftop | 12 | 2.15 | $0.89M | $412 | BELOW range; engineering review priority | HIGH | IEAT-direct |
| T2 ground-mount | 7 | 4.35 | $3.54M | $813 | mid-range | HIGH | IEAT-direct |
| T4A carport | 7 | 11.35 | $8.42M | $742 | lower bound | HIGH | IEAT-direct (all) |
| T4B-DC arterial | 16 | 1.83 | $1.28M | $700 | lower bound (single-mob conditional) | MEDIUM | mixed (per side) |
| T6W canal canopy | 5 | 14.91 | $10.91M | $732 | lower bound | MEDIUM | tenant-attributed (all) |
| BESS | 0 | 0 | $0 | $175/kWh + thermal | n/a (different basis: $/kWh) | n/a | LC no-BESS |
| TOTAL (PV) | 47 | 34.59 | $25.04M | weighted $724/kWp | within memory range | mixed | 52% IEAT / 48% tenant |
LC envelope split by typology: - T6W is largest single-typology contributor by CAPEX (44%) and capacity (43%) - T4A is the IEAT-direct flagship (33% by capacity, 34% by CAPEX, all IEAT-direct) - T1 + T2 + T4A (IEAT-direct family) = 19.85 MWp / $12.85M = 51% by CAPEX - T4B-DC + T6W (tenant-attributed family) = 16.74 MWp / $12.19M = 49% by CAPEX
The 52/48 split per LC IC paper §2 reflects the underlying typology distribution.
Memory-range observation: weighted average across all 5 PV typologies at LC is $724/kWp — within memory range. Four of five typologies are at or below the lower bound; T1 is below range. The weighted average lands inside the range largely because T6W (highest absolute CAPEX share, 44%) is at $732 — close to the lower bound but above it.
C.8 Acknowledged Part C gaps¶
- T1 unit cost below memory range ($412 vs $700–1,100 floor) — WP2 engineering review priority. Confirm LC-specific advantages explain the gap or revise the LC v1.0 number.
- Per-typology methodology canonical CAPEX does not exist — AUDIT-040 / Annex H is the deliverable. WP2 + WP4 engineering review produces per-typology canonical via documented LC-specific cost drivers compared against engineering-validated cost stack. Annex H lock is the gating event for the v1.1.0 methodology document.
- C4 corrosion premium application (AUDIT-002) — across all typologies for coastal estates; needs verification in unit cost build-up
- Bifacial uplift typology-specific values (AUDIT-041) — model uses estate-canonical only; per-typology uplifts need application
- T4B-DC single-mob vs phased per-estate decision — methodology assumes single-mob; if procurement forces phased, +25% premium applies
- T6W LC2 Power Plant power-producer ESA sub-class — formalise this offtaker type
- BESS revenue stack composition per estate — Part D treatment needs to specify weighting
- Per-typology cleaning / O&M frequency — methodology has flat $20/kWp/yr O&M base; per-typology breakdown (T6W monthly vs others quarterly) needs explicit Part D treatment (AUDIT-016)
- Reserve typology promotion rules (T1X / T2X / T6X) — methodology needs explicit Phase 0A/0B promotion criteria
These gaps are tracked in audit register (R3 v0.3) and folded into v1.1 work plan.
C.9 References¶
- NC-IS-LC-001 LC Investment Segment Register v1.0 — per-segment data for 47 active + aspirational
- NC-IC-LC-001 IC Paper v1.1 — investment thesis with per-typology breakdown
- NC-FM-LC-001 LC Financial Model v1.0 — Active_Envelope tab with per-typology data
- NC-MN-001-R3_audit_v0_3 — live audit register
- Memory edits 1–30 (per
memory_user_edits view12 May 2026); particularly edit 16 for solar $700–1,100/kWp canonical range - NC-METH-001 v1.1.0 Part A — framing conventions
- NC-METH-001 v1.1.0 Part B — pipeline stages B.2, B.3, B.5
End of Part C v1.1.0-revA.