NEXUS Utilities — Technical Design Specification

NEXUS™ Modular Utilities Interconnect — Four-Zone Overhead Architecture

Overhead Spine · Z1 Electrical · Z2 Thermal · Z3 Gas · Z4 Material & APS · Module Swappability Infrastructure

Doc No.CBT-NXS-TDS-001

RevisionRev 0

OER ClassClass 2 Target — Not Yet Released

DateApril 2026

Canonical400 TPD / 32 MW

ClassificationConfidential

Working Document — Pre-Release Engineering Development

Initial release. Authorized ARM-2026-002 §14. Four-zone architecture established ARM-2026-002 Cluster D. D-ZEP-APS-01 CLOSED — ZEP H&sub2; purge recycle routed to NXS-Z3 (no flare path). Open: D-H2-01 (NXS-Z3 pressure / pipe class), D-THM-02 (NXS-Z2 high-temp connector physical standard), D-48V-01 (Z1 controls bus), D-66 (PIMB footprint), D-67 (RMB footprint), D-ASI-01.

Document Number	`CBT-NXS-TDS-001`
Revision	Rev 0 — April 2026
Scope	Overhead Spine · NXS-Z1 Electrical · NXS-Z2 Thermal/Fluid · NXS-Z3 Gas · NXS-Z4 Material & APS
Canonical Basis	400 TPD / 32 MW / PIMB + RMB
Governing ARMs	ARM-2026-001 · ARM-2026-002
Revenue Baseline	RevCon 3 — $150M–$325M/yr, 400 TPD baseline
ASI	Authorized Strategic Integrator — pending D-ASI-01
Chairman	Allen Witters

1. Executive Summary

Near-Zero Design Intent

The NEXUS™ Modular Utilities Interconnect is engineered as a closed-loop manufacturing subsystem designed for near-zero emissions, near-zero discharge, and near-zero residual. All APS Capture Streams route via NXS-Z4 to internal recovery — no atmospheric discharge. No utility fluid is discharged to drain or to ambient without internal recovery first. Environmental performance outcomes contingent on execution at commercial scale and validated through SAT and FPT procedures.

NEXUS as Module-Swappability Infrastructure

NEXUS is the physical infrastructure that enables true module-swappability as a Serial-Numbered OEM Product design requirement. Module replacement requires only isolation of four overhead zone drops — no building intervention, no civil work, no underground access.

NEXUS™ is the Carbotura-branded overhead Modular Utilities Interconnect system. NEXUS is a Carbotura OEM product specification — not a site utility system. It is designed, assembled, tested, and warranted by the ASI to Carbotura specification.

NEXUS routes all four utility categories — electrical, thermal, gas, and material/APS — overhead within the PIMB and RMB. Zero utilities are routed underfloor or at grade within manufacturing buildings. Every module position receives standardized drops from all four zones.

At the 400 TPD canonical engineering baseline, NEXUS serves 16 Recyclotron reactor positions, 4 T2 processing positions, all Pregenesis module positions in the PIMB, and all Regenesis module positions in the RMB. NEXUS routes continuously through both buildings with an inter-building crossing at the PIMB/RMB shared wall via the ASI-RFH-FLG interface point.

2. Facility Context & Module Boundaries

2.1 System Position in the ACM Facility

NEXUS is the connecting infrastructure between all protocol-zone modules and all facility utility sources. It physically enables the Serialized Product Model — every module in the ACM Facility connects to NEXUS at defined interface points and no other location.

Buildings served	PIMB (Pregenesis building, with airlocks) and RMB (Regenesis building)
Routing principle	100% overhead within both buildings — zero underfloor, zero at-grade
Zone count	Four — NXS-Z1 (Electrical), NXS-Z2 (Thermal/Fluid), NXS-Z3 (Gas), NXS-Z4 (Material/APS)
Canonical basis	400 TPD / 16 Recyclotron reactors / full Pregenesis and Regenesis module complements
Inter-building interface	Overhead spine crosses at shared wall; feed header (ASI-RFH-FLG) at shared wall crossing
PIMB footprint	D-66 OPEN — governing value pending modular design review
RMB footprint	D-67 OPEN — governing value pending modular design review

2.2 Module Boundaries

Zone	NEXUS Upstream Boundary	NEXUS Downstream (Module Drop)
`NXS-Z1-ELEC`	ZEP MVDC Backbone aggregation point (ZEP-MVB-001 output)	ASI-PBK-QC device link at each module skid; ASI-ZBK-MPC zone bus tap; ASI-DAT-MOD-TCP data port
`NXS-Z2 (High-Temp)`	REG-WHSG-001 High-Temp Thermal outlet → NXS-Z2 high-temp header inlet	ASI-THM-HT drop valve at each T2-ITD and PRE-EVP-001 position
`NXS-Z2 (Low-Temp)`	ZEP-TRL-001 Zero-E Thermal Recovery Loop outlet	Low-temp hot water drop at each module position requiring preconditioning heat
`NXS-Z3 (H&sub2;)`	REG-BSH-001 H&sub2; buffer storage outlet	Dual-stage pressure regulation (ZEP-H2R) + HVIL-linked fail-closed valve at each position
`NXS-Z3 (N&sub2;)`	GPU N&sub2; generation unit	N&sub2; drop valve at each reactor injection position
`NXS-Z3 (recycle)`	ZEP PEM enclosure purge → APS-ZEP-001	Recycle return inlet at NXS-Z3 header (D-ZEP-APS-01 CLOSED)
`NXS-Z4 (APS)`	All process APS capture points throughout PIMB and RMB	APS main collection header → APS fan/recovery equipment
`NXS-Z4 (RFH)`	PIMB Shredder Train / RFB output	ASI-RFH-FLG (12-in. ANSI 150# RF) at PIMB/RMB shared wall

2.3 Excluded Scope

Zero-E PowerBlock generation equipment	ZEP scope — NEXUS receives at MVDC Backbone aggregation point
REG-BSH-001 H&sub2; buffer storage vessel	Regenesis scope
REG-WHSG-001 Process Gas Heat Recovery Unit	Regenesis scope
APS fan units, filters, and recovery equipment	APS Protocol scope — NEXUS provides Z4 ductwork collection spine only
GPU N&sub2; generation unit	Owner-supplied utility at battery limit
Instrument air compressors	Owner-supplied utility at battery limit
Module skid equipment	Per protocol TDS
PIMB and RMB structural steelwork for NEXUS support	Structural engineering scope — NEXUS provides load data

3. Process Description

3.1 Zone-by-Zone Narrative

NXS-Z1 — Electrical Spine

Zone 1 is the overhead electrical and data distribution spine serving all module positions in both buildings. The 20kV MVDC Backbone routes overhead from the Zero-E PowerBlock aggregation point through cable trays to each zone bus segment (ZEP-ZBS). From each zone bus segment, 1,500V DC zone bus drop cables feed local 250 kW PEM module device links via Amphenol ePower-Lite connectors (ASI-PBK-QC). Safety interlock chain hardwire and Modbus TCP/IP data cable run in the same Z1 cable tray zone, physically separated from power cables. The 48V DC controls bus routes in Z1 pending D-48V-01 resolution.

NXS-Z2 — Thermal and Fluid Spine

Zone 2 is the overhead insulated pipe rack carrying two thermally distinct circuits. The High-Temperature Thermal header (200–400°C, steam or thermal oil — D-THM-02 physical standard open) carries WHSG thermal recovery from REG-WHSG-001 to T2-ITD dryers and PRE-EVP-001 evaporators via ASI-THM-HT drop connections. The Low-Temperature Thermal header (85–95°C, water-glycol) carries the Zero-E Thermal Recovery Stream from ZEP-TRL-001. Both headers run on thermally isolated pipe rack sections. Process cooling water supply and return run in Z2 as a third circuit.

NXS-Z3 — Gas Spine

Zone 3 is the overhead pipe rack carrying H&sub2;, N&sub2;, compressed air, and recycle gas. The H&sub2; high-pressure distribution header supplies PEM module positions via dual-stage regulation stations (ZEP-H2R-001 to -004) and HVIL-linked fail-closed valves — no H&sub2; flows downstream of a failed HVIL. The N&sub2; header supplies the Dense-Phase N&sub2; Pneumatic Injection System at each Recyclotron reactor position. The ZEP H&sub2; purge recycle return line connects into the NXS-Z3 recycle header at each PEM enclosure — D-ZEP-APS-01 CLOSED, no flare path. NXS-Z3 sized for both primary H&sub2; distribution and recycle return (50–120 CFM aggregate purge, 400 CFM peak).

NXS-Z4 — Material and APS Spine

Zone 4 is the overhead APS Capture Stream ductwork collection spine and material transfer routing. All APS capture points throughout PIMB and RMB connect to the Z4 main collection duct via ASI-APS-FLG flange connections. Zone 4 also carries the Recyclotron Feed Header (RFH) — the 12-in. ANSI 150# RF carbon steel rubber-lined transfer pipe (ASI-RFH-FLG) — from PIMB Shredder Train RFB output to the PIMB/RMB shared wall crossing. Zone 4 is physically separated from Zones 1–3 on a dedicated structure to prevent APS Capture Stream cross-contamination of electrical or fluid infrastructure.

3.2 Module Drop Standard — Per Position

Every module position receives a standardized four-zone drop set. Module replacement requires only isolation of these four drop points:

Drop	Zone	Isolation Device	Reconnect Connector
Electrical device link	Z1	HVIL break — automatic H&sub2; isolation + circuit isolation	ASI-PBK-QC
Zone bus tap	Z1	DC isolator switch	ASI-ZBK-MPC
Data port	Z1	Network patch disconnect	ASI-DAT-MOD-TCP
High-temp thermal	Z2	Isolation valve (manual + actuated)	ASI-THM-HT
Low-temp thermal	Z2	Isolation valve (manual)	ASI-THM-ZE
H&sub2; supply	Z3	HVIL-linked pneumatic fail-closed valve	ASI-H2-HPS
N&sub2; supply	Z3	Manual isolation valve	1-in. NPT (standard)
Compressed air	Z3	Manual isolation valve	½-in. NPT (standard)
APS capture duct	Z4	Manual butterfly damper	ASI-APS-FLG
RFH (Recyclotron only)	Z4	Manual ball valve	ASI-RFH-FLG

3.3 Inter-Building Spine Crossing

All four NEXUS zones cross the PIMB/RMB shared wall via dedicated penetrations with fire-rated seals. The crossing is continuous routing through the wall — not a break in the spine. The RFH (ASI-RFH-FLG) is the only positively pressured manufacturing stream crossing this wall.

4. Design Envelope

NEXUS distributes facility utilities and collects APS Capture Streams. It does not process manufacturing feedstock.

4.1 Utility Supply Specifications at NEXUS Battery Limit

Utility	Zone	Supply Spec	Status
20kV MVDC Backbone	Z1	32 MW at 400 TPD from ZEP-MVB-001	LOCKED — ZEP-TDS-001
WHSG High-Temp Thermal	Z2	200–400°C / 10–40 bar (steam or oil) — 2–8 MW thermal	CLOSED PARAMETRIC — D-35, D-THM-01
Zero-E Thermal Recovery Stream	Z2	85–95°C water-glycol — ~1.5–3.0 MW thermal	LOCKED — ZEP-TDS-001 Cluster G
H&sub2; supply	Z3	≥99.97% ISO 14687 Type D · Pressure D-H2-01 OPEN (20–50 bar parametric)	OER Gate 2 — D-H2-01
N&sub2; supply	Z3	≥99.999% (5N) · 8–12 bar · dew point ≤–40°C	OER Gate 2 OEM
Instrument compressed air	Z3	Oil-free · 7 bar · dew point ≤–40°C	OER Gate 2 OEM
APS capture pressure	Z4	Negative pressure at all Z4 APS capture points	APS Protocol scope
H&sub2; purge recycle return	Z3	50–120 CFM aggregate (400 CFM peak)	DEFINED — D-ZEP-APS-01 CLOSED

4.2 Design Envelope Limits

Condition	Consequence	Interlock Response
H&sub2; supply pressure below minimum regulation envelope	All HVIL-linked zones — PEM modules isolate	HVIL fail-closed at every Z3 H&sub2; drop
MVDC Backbone loss	All module positions lose power — Black Start sequence	ZEP-BSS-001 Black Start protocol
APS Z4 negative pressure loss	APS capture fails — process zones remain enclosed but recovery path interrupted	APS fault alarm
WHSG thermal supply loss	T2-ITD and PRE-EVP-001 lose heating — production derate	T2-ITD and EVP derate per OPS

5. Module Equipment Specifications

5.1 NXS-Z1 — Electrical Spine Infrastructure

Function	Overhead distribution of 20kV MVDC Backbone, 1,500V DC zone bus, 800V DC device links, 48V controls bus (D-48V-01), Modbus TCP/IP data, safety hardwire to all module positions
MVDC Backbone routing	Overhead cable tray — 20kV MVDC, HARTING Han® HPR (ASI-MVDC-HPR)
Zone bus routing	1,500V DC liquid-cooled laminated busbars — overhead per zone; Stäubli MPC (ASI-ZBK-MPC)
Device link drops	800V DC, Amphenol ePower-Lite (ASI-PBK-QC), <3 m run to module skid
Data routing	Modbus TCP/IP over shielded Cat6A — overhead cable tray, physically separated from power cables
Safety hardwire	HVIL chain hardwire — physically separate from data cables within Z1 tray
48V controls bus	D-48V-01 OPEN — overhead if retained; eliminated if D-48V-01 resolves against retention
Cable tray type	Aluminum ventilated cable tray — NEMA VE-1; NEC Article 392
CAPEX	$1.5M–$4.5M parametric [Class 2 ±15%, 2026 USD]

5.2 NXS-Z2 — Thermal and Fluid Spine Infrastructure

Function	Overhead insulated pipe rack routing WHSG High-Temp Thermal, Zero-E Thermal Recovery Stream, process cooling water, and building heating hot water
High-temp thermal header	200–400°C / 10–40 bar · 316L SS or Inconel-lined CS (pending D-THM-02) · mineral wool insulation · expansion loops each building section · Connector: ASI-THM-HT (D-THM-02 OPEN)
Low-temp thermal header	Water-glycol 85–95°C · 316L SS · closed-cell foam · ASI-THM-ZE
Process cooling water	CS with corrosion inhibitor · OER Gate 2 OEM cooling load confirmation
Pipe rack type	Overhead insulated pipe rack — thermally segregated sections per fluid service · minimum 3 m clearance above finished floor
CAPEX	$1.8M–$5.5M parametric [Class 2 ±15%, 2026 USD]

5.3 NXS-Z3 — Gas Spine Infrastructure

Function	Overhead pipe rack routing H&sub2; high-pressure, N&sub2;, instrument/utility compressed air, vacuum, and H&sub2; purge recycle return
H&sub2; high-pressure header	D-H2-01 supply pressure (20–50 bar parametric) · 316L SS (700-bar conservative per ZEP-TDS-001 R-02) · HVIL-linked pneumatic fail-closed valve at each drop · ASI-H2-HPS · H&sub2; point detectors at 10 m intervals
H&sub2; purge recycle return	ZEP PEM enclosure purge — 50–120 CFM aggregate / 400 CFM peak · 316L SS · check valve at each return inlet · flow totalizer at ZEP-BSH-001 inlet
N&sub2; header	8–12 bar · ≥99.999% · CS · sized for Dense-Phase N&sub2; peak demand (D-46 OPEN)
Instrument compressed air	Oil-free 7 bar · CS with stainless sub-headers at actuated valve drops
Gas detection	Continuous H&sub2; monitoring along full Z3 header · 10% LFL alarm · 25% LFL auto-isolation · SCADA via ASI-DAT-MOD-TCP
CAPEX	$1.2M–$3.8M parametric [Class 2 ±15%, 2026 USD]

5.4 NXS-Z4 — Material and APS Spine Infrastructure

Function	Overhead APS Capture Stream ductwork collection spine and Recyclotron Feed Header (RFH) routing. Physically isolated from Zones 1–3.
APS collection duct	16-gauge galvanized steel · fan-maintained negative pressure · ASI-APS-FLG at each capture point · OER Gate 2 sizing
Recyclotron Feed Header	Conditioned Manufacturing Feedstock from SHRD-RFB to Recyclotron feed airlock · 12-in. ANSI 150# RF CS rubber-lined · ASI-RFH-FLG · overhead through PIMB/RMB shared wall
Zone 4 physical isolation	Z4 structure physically separated from Z1/Z2/Z3 throughout both buildings. No shared cable tray, pipe rack, or structural member. (ARM-2026-002 §5.3)
CAPEX	$0.8M–$2.5M parametric [Class 2 ±15%, 2026 USD]

5.5 Overhead Structural Spine

Function	Structural support for all four NEXUS zones within both PIMB and RMB · transfers NEXUS loads to building structure at Owner-specified support points
Minimum clearance	3 m clear above finished manufacturing floor at all module positions (ARM-2026-002 §5.2)
Material	Structural steel — hot-dip galvanized
Span	Building column spacing — pending D-66/D-67 footprint resolution
Load data	NEXUS provides loads to Owner structural engineer at OER Gate 2
CAPEX	Included in zone CAPEX line items above

6. APS Interface Register

APS Process-Capture Basis Statement

All Zone 4 APS capture points represent internal recovery streams — not atmospheric emissions. NXS-Z4 is the collection spine only. APS fan units, filters, and recovery equipment are APS Protocol scope (CBT-APS-TDS-001).

APS Point	Tag	Source	Normal CFM	Connector	Status
Pregenesis module APS capture points (aggregate)	APS-PRE-NXS	All Pregenesis process APS points	Per PRE-TDS §6 — not summed at Rev 0	ASI-APS-FLG	DEFINED per protocol TDS
Regenesis module APS capture points (aggregate)	APS-REG-NXS	All Regenesis process APS points	Per REG-TDS §6 — not summed at Rev 0	ASI-APS-FLG	DEFINED per protocol TDS
ZEP PEM H&sub2; purge recycle return	APS-ZEP-001	ZEP-PEM enclosure purge — routes to NXS-Z3, not Z4	50–120 CFM / 400 CFM peak (Z3 scope)	ASI-APS-FLG (APS side)	D-ZEP-APS-01 CLOSED — Z3 recycle
BESS off-gas	APS-ZEP-002	ZEP-BSS-001 battery enclosure	20–40 CFM / 200 CFM fault	ASI-APS-FLG	DEFINED — Z4 APS

Note: Total facility APS CFM will be formally summed at OER Gate 2 when CBT-APS-TDS-001 is produced. The Z4 duct shall be sized on basis of the consolidated APS CFM register.

7. Modular Installability & ICD

SAT/FPT Statement

SAT and FPT will be conducted following module assembly and initial startup. A 72-hour continuous TPGT is required witnessed by Carbotura Engineering, Owner's Engineer, and an independent third party.

ICD Reference	Interface	Connection Type	ASI Standard	Test Requirement	Status
ICD-NXS-Z1-MVDC-001	ZEP MVDC Backbone → NXS-Z1 spine inlet	20kV MVDC, HARTING Han® HPR	ASI-MVDC-HPR	FAT: full 32 MW energize through NXS-Z1; cable tray continuity and insulation resistance	DEFINED — ARM-2026-002
ICD-NXS-Z1-ZBS-001	NXS-Z1 zone bus → ZEP Zone Bus Segment tap	1,500V DC liquid-cooled busbar	ASI-ZBK-MPC	FAT: 8 MW per zone at tap; busbar temperature within limits at full load	DEFINED
ICD-NXS-Z1-PBK-001	NXS-Z1 device link drop → module skid	800V DC, Amphenol ePower-Lite, <3 m	ASI-PBK-QC	FAT: each module position live at 250 kW; HVIL trip test per position	DEFINED
ICD-NXS-Z1-DAT-001	NXS-Z1 data drop → module SCADA connection	Modbus TCP over shielded Cat6A	ASI-DAT-MOD-TCP	FAT: all positions in SCADA with GREEN; alarm propagation test	DEFINED
ICD-NXS-Z2-THM-HT-001	REG-WHSG-001 → NXS-Z2 high-temp thermal header	200–400°C / 10–40 bar	ASI-THM-HT	FAT: thermal header at operating temp; drop valves operable; insulation surface <60°C	OPEN — D-THM-02 physical standard OER Gate 2
ICD-NXS-Z2-THM-ZE-001	ZEP-TRL-001 → NXS-Z2 low-temp thermal header	Water-glycol 85–95°C	ASI-THM-ZE	FAT: coolant 85–95°C at all drops; pump flow confirmed	DEFINED — ARM-2026-002 Cluster G
ICD-NXS-Z3-H2-001	REG-BSH-001 → NXS-Z3 H&sub2; header	High-pressure H&sub2; — pipe class pending D-H2-01	ASI-H2-HPS	FAT: H&sub2; header pressure at all drops; HVIL isolation <50 ms per position; no-leak at rated pressure	OPEN — D-H2-01 OER Gate 2
ICD-NXS-Z3-H2R-001	NXS-Z3 H&sub2; header → ZEP-H2R regulation station	H&sub2; high-pressure → intermediate (~20 bar D-H2-01)	ASI-H2-HPS	FAT: regulation accuracy ±2%; HVIL function per station	OPEN — D-H2-01
ICD-NXS-Z3-RCY-001	ZEP PEM enclosure purge → NXS-Z3 recycle return	316L SS — ambient pressure recycle return	ASI-APS-FLG (APS side)	FAT: recycle flow via totalizer; check valve no backflow; H&sub2; sensor <10% LFL	DEFINED — D-ZEP-APS-01 CLOSED
ICD-NXS-Z4-APS-001	All process APS capture → NXS-Z4 collection duct	APS duct flange	ASI-APS-FLG	FAT: negative pressure at all Z4 connection points; no APS stream at non-capture points	DEFINED per protocol APS registers
ICD-NXS-Z4-RFH-001	PIMB SHRD-RFB → shared wall → Recyclotron feed	12-in. ANSI 150# RF CS rubber-lined	ASI-RFH-FLG	FAT: flow continuity; no blockage at crossing; rubber lining intact	LOCKED — ECN-004

8. Utilities Register

NEXUS is primarily a utilities distribution system. Internal parasitic consumption is the electrical loads of valve actuators, instrumentation, gas detection, and SCADA within the spine itself.

NXS-Z1-ELEC — Electrical (Consumed by NEXUS Internal Systems)

Load	P50 (kW)	P90 (kW)	Notes
HVIL solenoid valve actuators (Z3 H&sub2; drops, all positions)	3	8	~16 valves at 400 TPD; energized to open, fail-closed
Thermal isolation valve actuators (Z2 high-temp drops)	2	4	Motorized valves at T2-ITD and EVP positions
Gas detection system (H&sub2; sensors, Z3)	1	2	Continuous 24/7 monitoring
NEXUS SCADA I/O	1	2	Valve position feedback, gas detection, thermal monitoring
Pipe heat tracing (Z2 high-temp startup assist)	5	15	Active during startup only
Total NEXUS internal electrical	~12 kW	~31 kW	Negligible vs. 32 MW facility generation

NXS-Z2-FLUID — Thermal (Distributed)

Stream	Value	Notes
WHSG High-Temp Thermal → T2-ITD and EVP	2–8 MW thermal at 400 TPD	200–400°C / 10–40 bar (D-THM-01 CLOSED PARAMETRIC)
Zero-E Thermal Recovery → preconditioning	~1.5–3.0 MW thermal at 400 TPD	85–95°C

NXS-Z3-GAS — Gas (Distributed)

Stream	Rate	Notes
H&sub2; to PEM modules	640–742 kg/hr at 400 TPD (parametric)	Per ZEP-TDS-001 §8
N&sub2; to Dense-Phase Injection System	D-46 OPEN — SLR test required	Per 16 reactors at 400 TPD
H&sub2; purge recycle return	50–120 CFM aggregate at 400 TPD	D-ZEP-APS-01 CLOSED — Z3 recycle

9. Vendor Matrix

American Manufacturing Preference Policy (ARM-2026-002 Cluster H) applies throughout. All compliance status preliminary — verification required at RFQ stage.

Equipment	Vendor	Country	Procurement Path	Lead Time
Aluminum Cable Tray (Z1)	Legrand (Cablofil)	USA (Franklin, TN)	Direct — US Manufacturer	8–14
Aluminum Cable Tray (Z1)	Atkore International	USA (Harvey, IL)	Direct — US Manufacturer	8–12
20kV MVDC Cable (Z1 backbone)	Southwire	USA (Carrollton, GA)	Direct — US Manufacturer	12–20
20kV MVDC Cable (alt)	General Cable (Prysmian US)	USA (Highland Heights, KY)	Direct — US Manufacturer	12–20
Insulated Pipe Rack (Z2/Z3)	Bergen-Power Pipe Supports	USA (Rutland, VT)	Direct — US Manufacturer	14–22
Pipe Rack Structural Steel	Any AISC-certified US fabricator	USA	Direct — US Manufacturer	16–24
316L SS Piping (Z2/Z3 service)	Outokumpu Stainless USA	USA (Calvert City, KY)	Direct — US Manufacturer	10–18
High-Temp Thermal Insulation (Z2)	Owens Corning	USA (Toledo, OH)	Direct — US Manufacturer	6–12
H&sub2; HVIL Pneumatic Fail-Closed Valves	Emerson (Fisher Controls)	USA (Marshalltown, IA)	Direct — US Manufacturer	14–26
H&sub2; HVIL Valves (alt)	Parker Hannifin	USA (Cleveland, OH)	Direct — US Manufacturer	12–22
H&sub2; Gas Detection (Z3)	MSA Safety	USA (Cranberry Township, PA)	Direct — US Manufacturer	10–16
H&sub2; Gas Detection (alt)	Industrial Scientific (Fortive)	USA (Pittsburgh, PA)	Direct — US Manufacturer	10–16
APS Ductwork (Z4)	Any SMACNA-certified US sheet metal fabricator	USA	Direct — US Manufacturer	10–18
Thermal Expansion Joints (Z2)	Flexicraft Industries	USA (Chicago, IL)	Direct — US Manufacturer	12–20
Pipe Insulation — Closed-Cell (Z2 LT)	Armacell	USA (Mebane, NC)	Direct — US Manufacturer	6–10

10. CAPEX Estimate

Line Item	Low	High	Basis
NXS-Z1 — Electrical spine	$1.5M	$4.5M	Linear infrastructure per building footprint — pending D-66/D-67
NXS-Z2 — Thermal/fluid spine	$1.8M	$5.5M	Insulated pipe rack at 200–400°C service; D-THM-02 open adds uncertainty
NXS-Z3 — Gas spine	$1.2M	$3.8M	H&sub2; pipe class conservative basis (700-bar); D-H2-01 resolution may reduce
NXS-Z4 — Material/APS spine	$0.8M	$2.5M	Standard galvanized ductwork + RFH pipe
Overhead structural support	$0.5M	$1.5M	Standard structural steel — pending D-66/D-67
E&I — NEXUS-scope instrumentation	$0.5M	$1.5M	8–10% of equipment subtotal
ASI Integration, Assembly, FAT	$0.6M	$1.8M	8–10% of equipment subtotal
Contingency (15%)	$1.0M	$3.2M	AACE Class 2
TOTAL Module CAPEX — 400 TPD	$7.9M	$24.3M	[Class 2 ±15%, 2026 USD]
Per 100 TPD increment	$2.0M	$6.1M	Approximately linear

AACE Classification: Class 2 ±15% — 2026 USD basis. Primary uncertainty drivers: (1) building footprint (D-66/D-67 — spine length unknown); (2) H&sub2; service pipe class (D-H2-01 — 700-bar conservative may overstate); (3) high-temp thermal connector (D-THM-02).

Included: All NXS-tagged spine infrastructure, overhead structure, valve actuators, gas detection, E&I, ASI assembly and FAT. Excluded: APS fan units and recovery (APS Protocol), module skid equipment (protocol TDS), building structure (Owner).

11. TIC WBS Reconciliation

WBS Item	Incl.	Notes
NXS-Z1 cable tray, cable, connectors	✅	Per §10
NXS-Z2 pipe rack, thermal piping, insulation, valves	✅	Per §10
NXS-Z3 gas headers, gas detection, HVIL valves, recycle sub-header	✅	Per §10
NXS-Z4 APS ductwork spine, RFH pipe	✅	Per §10
Overhead structural steel for NEXUS support	✅	Per §10
E&I (NEXUS scope)	✅	Per §10
ASI FAT and Unitized Warranty Passport	✅	Per §10
APS fan units, filters, recovery equipment	❌	APS Protocol scope
Building structure (columns, roof, floor)	❌	Owner scope
Site utility connections at battery limit	❌	Owner scope
GPU N&sub2; generation unit	❌	Owner-supplied utility
Instrument air compressors	❌	Owner-supplied utility

12. Lead Time Schedule

Equipment	Lead Time	Critical Path?	Notes
H&sub2; HVIL valve assemblies	14–26 wks	MEDIUM	Safety-critical custom H&sub2; service; order early
20kV MVDC cable (Z1 backbone)	12–20 wks	MEDIUM	Custom voltage rating; limited US suppliers
High-temp thermal piping (Z2)	10–18 wks	LOW	Standard stainless; adequate supplier base
APS ductwork (Z4)	10–18 wks	LOW	Standard fabrication
Structural steel (overhead support)	16–24 wks	MEDIUM	Requires D-66/D-67 before fabrication drawings
Cable tray (Z1 aluminum)	8–14 wks	LOW	Catalog product
Pipe insulation and expansion joints	6–12 wks	LOW	Standard industrial

Critical path note: NEXUS is not the facility critical path — Recyclotron reactors, PEM modules, and MVDC switchgear have longer lead times. However, NEXUS structural support design cannot begin until D-66/D-67 building footprints are resolved. Issue structural steel RFQ within 4 weeks of D-66/D-67 closure.

13. TRL / ERL / IRL Assessment

Equipment / Zone	TRL	ERL	IRL	Notes
NXS-Z1 — Cable tray, MVDC cable	9	8	7	Fully commercial. 20kV DC less common than AC but available from US OEMs. IRL limited by D-ASI-01.
NXS-Z1 — Zone bus and device link	8	7	6	Liquid-cooled busbars at 1,500V DC — commercial with custom sizing. HVIL integration well-defined.
NXS-Z2 — High-temp thermal header	8	6	5	Industrial pipe at 200–400°C is standard. IRL limited by D-THM-02 and D-THM-01.
NXS-Z2 — Low-temp thermal header	9	8	7	Standard water-glycol closed loop — fully commercial.
NXS-Z3 — H&sub2; header	8	6	4	H&sub2; high-pressure piping at facility scale has refinery/HRS precedent. IRL=4 reflects D-H2-01 open and D-ASI-01 open.
NXS-Z3 — N&sub2; header	9	8	6	Standard nitrogen piping. IRL limited by D-46 (flow rate unknown).
NXS-Z3 — Purge recycle sub-header	8	7	6	Ambient-pressure recycle return — standard SS. D-ZEP-APS-01 CLOSED.
NXS-Z4 — APS ductwork	9	8	6	Standard negative-pressure ductwork — SMACNA design.
NXS-Z4 — RFH (12-in. CS rubber-lined)	9	8	7	Standard industrial pipe. ECN-004 locked.
System-Level NEXUS	8	6	4	Limited by H&sub2; piping and high-temp thermal. IRL=4 driven by D-H2-01 and D-THM-02. Both resolve at OER Gate 2.

14. Confidence Factor

Assessment Dimension	Weight	Score (1–5)	Weighted	Basis
Technology maturity	25%	4.5	1.13	Primarily standard industrial infrastructure — cable tray, pipe rack, ductwork
Interface definition completeness	20%	3.0	0.60	D-H2-01 and D-THM-02 open — Z3 and Z2 interfaces partially defined
Vendor availability (US market)	15%	4.5	0.68	Strong US market for all NEXUS equipment categories
CAPEX basis quality	20%	2.5	0.50	Building footprint open (D-66/D-67) — spine length determines cost
Open decision exposure	10%	2.8	0.28	D-H2-01, D-THM-02, D-66, D-67 all open — four primary confidence limiters
Scaling precedent	10%	4.0	0.40	Industrial overhead pipe rack and cable tray at this scale is well-established
Total Confidence Factor	100%	—	3.59 / 5.00 (72%)	Consistent with Class 2 working document at first release

Interpretation: 72% — NEXUS underlying technology entirely commercially mature. Confidence limited by open design decisions (D-66/D-67 footprint, D-H2-01 H&sub2; pressure, D-THM-02 connector) rather than technology uncertainty. All four confidence limiters are procurement/OEM decisions, not engineering unknowns. Confidence will increase substantially at OER Gate 2.

15. Availability Model

Zone	MA (%)	MTBF (hrs)	MTTR (hrs)	Notes
NXS-Z1 — Electrical spine	99.9%	175,200	16	Static passive infrastructure; primary failure mode is connector degradation
NXS-Z2 — Thermal/fluid headers	99.5%	43,800	44	Isolation valve actuators primary maintenance; expansion joints periodic inspection
NXS-Z3 — Gas spine	99.5%	43,800	44	HVIL valve function primary maintenance item; annual leak test
NXS-Z4 — APS/RFH	99.7%	87,600	28	APS dampers periodic inspection; RFH rubber lining inspected annually
System-Level NEXUS	99.2%	—	—	Individual zone outages don't take down entire facility — zone isolation maintained

Availability note: A single zone outage does not shut down the facility. Module-level isolation means only the affected module position goes offline during a zone maintenance event. Zone-level maintenance can be sequenced to minimize production impact.

16. Risk Register

R-01 HIGH — Building Footprint Open (D-66 / D-67) — Scope / Schedule

NEXUS spine length, structural support span, pipe/cable quantities, and total CAPEX are directly proportional to building footprint. D-66 (PIMB) and D-67 (RMB) are both open. Without footprint confirmation, CAPEX range remains wide and structural steel RFQs cannot be issued.

Mitigation: (1) Complete modular design review and close D-66/D-67 — highest-impact action for NEXUS scope definition. (2) Proceed with NEXUS zone architecture, connector family confirmation, and equipment vendor qualification in parallel. (3) At OER Gate 2, issue structural steel RFQ within 4 weeks of D-66/D-67 closure.

R-02 HIGH — D-H2-01 Open: H&sub2; Header Pressure and Pipe Class — Integration / Safety

NXS-Z3 H&sub2; header pipe wall thickness, material grade, fitting ratings, and HVIL valve specifications are governed by supply pressure (D-H2-01 — 20–50 bar parametric). Until D-H2-01 closes with REG-BSH-001 OEM confirmation, Z3 H&sub2; spine cannot be detailed designed or procured. The conservative 700-bar basis protects against rework but may overstate cost.

Mitigation: (1) Close D-H2-01 at OER Gate 2 with REG-BSH-001 OEM selection. (2) Maintain 700-bar conservative basis until D-H2-01 closes. (3) Pre-qualify Emerson and Parker Hannifin HVIL valve assemblies for both 350-bar and 700-bar service.

R-03 MEDIUM — D-THM-02 Open: Z2 High-Temp Connector Physical Standard — Integration / ICD

The ASI-THM-HT physical connector standard for NXS-Z2 high-temperature thermal drops is open (D-THM-02). Until fluid type (steam vs. thermal oil) and operating pressure are confirmed by WHSG OEM, drop valve spec and flange rating for T2-ITD and PRE-EVP-001 connections cannot be finalized.

Mitigation: (1) Close D-THM-02 at OER Gate 2 with WHSG OEM confirmation. (2) Design Z2 pipe rack to accommodate either steam or thermal oil service. (3) Leave drop valve positions unspecified at Class 2 stage.

R-04 LOW — N&sub2; Header Sizing (D-46 Open) — Scope / Integration

N&sub2; header flow rate and pipe sizing are open pending D-46 (N&sub2; injection SLR). Dense-Phase N&sub2; System demand at 16 reactors (400 TPD) not confirmed.

Mitigation: (1) Size N&sub2; header at OER Gate 2 per D-46 SLR test result. (2) Conservatively size at Class 2 stage for 150% of estimated peak demand.

17. Spares Register

Crit.	Item	Qty First Fill	Qty Operating	Notes
A	HVIL pneumatic fail-closed valve assembly (Z3 H&sub2;)	4 assemblies	2/yr	Safety-critical; H&sub2; service; 14–26 week lead
A	Z2 high-temp thermal isolation valve (ASI-THM-HT compatible)	2 valves	1/yr	High-temp; failure isolates T2-ITD or EVP position
A	H&sub2; gas detection sensor (point detector, Z3)	8 sensors	4/yr	Replace on drift or annual calibration failure; 10–16 week lead
B	Thermal expansion joint — Z2 high-temp header	2 joints	1/yr	Inspect annually; replace at first sign of bellows fatigue
B	ASI-PBK-QC connector assembly (Z1 device link)	10 assemblies	4/yr	Connector cycling during module replacement
B	ASI-APS-FLG duct flange and gasket set	8 sets	2/yr	Z4 APS connection point; replace gasket on any maintenance
B	ASI-RFH-FLG flange and rubber-lined spool (12-in.)	2 spools	Per inspection	RFH rubber lining inspected annually; replace on >10% wear
C	Cable tray splice connector set (Z1 aluminum)	1 box per type	Per need	Low failure rate
C	Pipe insulation repair kit (Z2 mineral wool)	4 kits	1/yr	Repair damaged insulation; annual inspection
C	Closed-cell foam insulation repair kit (Z2 LT)	2 kits	Per need	Low failure rate

18. Warranty Register

Equipment	Warranty Period	OEM Guarantee	Coverage / Notes
NXS-Z1 — Cable tray and racking system	18 months from FAT	Yes — OEM via ASI	Structural integrity and finish quality guaranteed. Cable tray load rating confirmed at FAT.
NXS-Z1 — 20kV MVDC cable (Z1 backbone)	24 months from FAT	Yes — OEM direct	Insulation integrity, current capacity, dielectric strength guaranteed.
NXS-Z1 — ASI-PBK-QC and ASI-ZBK-MPC connectors	18 months from FAT	Yes — OEM via ASI	Electrical rating and mechanical function guaranteed. HVIL function per connector.
NXS-Z2 — High-temp thermal header piping	24 months from FAT	Yes — ASI	Leak-free at rated pressure/temperature. Insulation surface <60°C at rated service.
NXS-Z2 — Thermal expansion joints	18 months from FAT	Yes — OEM via ASI	Rated cycle life guaranteed. Bellows leak-free during warranty.
NXS-Z2 — Low-temp thermal header	18 months from FAT	Yes — ASI	Leak-free. Coolant delivery at 85–95°C confirmed at FAT.
NXS-Z3 — H&sub2; high-pressure header	24 months from FAT	Yes — ASI	Leak-free at rated H&sub2; service pressure. HVIL valve isolation <50 ms per position.
NXS-Z3 — H&sub2; purge recycle sub-header	18 months from FAT	Yes — ASI	Leak-free. Check valve function confirmed at FAT.
NXS-Z3 — N&sub2; and compressed air headers	18 months from FAT	Yes — ASI	Leak-free at rated service pressure.
NXS-Z4 — APS collection ductwork	18 months from FAT	Yes — ASI	Negative pressure at all capture points. Duct leak-free at design static pressure.
NXS-Z4 — RFH (12-in. CS rubber-lined)	18 months from FAT	Yes — ASI	Rubber lining integrity confirmed at FAT. Flow continuity at rated capacity.

18.1 Warranty Administration

The ASI (pending D-ASI-01) is the single point of warranty contact for all NEXUS sub-tier OEM suppliers. The Unitized Warranty Passport issued at FAT covers the full NEXUS system as an integrated overhead infrastructure product. Individual zone warranties pass through the Unitized Warranty Passport framework. Carbotura Engineering maintains the warranty log per ISO 9001:2015 Clause 8.7.

Open Decisions — NXS-TDS-001 Governing

D-#	Description	Priority	Blocks
`D-H2-01`	H&sub2; distribution header pressure — 20–50 bar parametric	OER Gate 2	NXS-Z3 pipe class, HVIL valve spec, ASI-H2-HPS physical standard
`D-THM-02`	ASI-THM-HT physical connector standard	OER Gate 2	NXS-Z2 high-temp drop valve spec; ICD-NXS-Z2-THM-HT-001 finalization
`D-48V-01`	48V DC controls bus — retained in NXS-Z1?	OER Gate 2	Z1 cable tray capacity; ICD tables
`D-66`	PIMB footprint	Modular design review	NXS spine length, structural steel RFQ, total CAPEX
`D-67`	RMB footprint	Modular design review	NXS spine length, structural steel RFQ, total CAPEX
`D-46`	N&sub2; injection SLR — conveying test	OER Gate 2	NXS-Z3 N&sub2; header sizing
`D-ASI-01`	ASI Vendor Selection	OER Gate 0	All procurement, FAT, Unitized Warranty Passport

Closed This Document

D-#	Resolution
`D-ZEP-APS-01`	CLOSED — H&sub2; purge gas routing = NXS-Z3 recycle. No flare path. NXS-Z3 recycle sub-header confirmed NEXUS scope. Forward input from CBT-ZEP-TDS-001 Rev 0.