⚠ ECN Pending — MVDC Backbone Voltage Correction
Session 9 (April 2026) issued an ARM-2026-002 correction: MVDC Backbone voltage for >100 TPD facilities is
30kV MVDC, not 20kV. This page reflects Rev 0 content as authored (20kV throughout). An ECN will supersede with Rev 1 updating all 20kV references to 30kV MVDC. Stäubli MPC zone bus (1,500V DC) and Amphenol ePower-Lite device link (800V DC) are unchanged.
Document Control
| Document Number | CBT-ZEP-TDS-001 |
| Revision | Rev 0 — April 2026 |
| OER Classification | Class 2 (±15%) OEM Engineering Release — equivalent to "FEED / DOE FEL-3" [external regulatory reference — DOE LPO / AACE 18R-97 only] |
| Status | WORKING DOCUMENT — Pre-Release Engineering Development |
| Owner | Carbotura Inc. — Engineering |
| Quality Standard | ISO 9001:2015 |
| Governing ARMs | ARM-2026-001 │ ARM-2026-002 |
| Authorized Strategic Integrator (ASI) | Vendor to be selected per D-ASI-01. All references to "ASI" indicate role pending final partnership execution. |
| Canonical Basis | 400 TPD / 32 MW / 128 PEM Modules / 4 Zones |
| Scaling | 8 MW per 100 TPD increment — linear to 80 MW at 1,000 TPD Single-Building Maximum |
| Classification | ISC-2 Confidential |
Revision History
| Rev | Date | Author | Description |
|---|
| 0 | April 2026 | Lead Systems Architect | Initial release. Authorized ARM-2026-002 §14. Nested DC Topology established (Cluster A, D-HVDC-01 CLOSED). PEM architecture (Cluster B). BESS and Black Start (Cluster C). Zero-E Thermal Recovery Stream (Cluster G). Scale nomenclature (Cluster I). D-ZEP-APS-01 CLOSED — H₂ purge → NXS-Z3 recycle. Open: D-H2-01, D-48V-01, D-THM-02, D-ASI-01. |
1. Executive Summary
Document Boundary Statement
This Technical Design Specification defines module-level technical requirements, interfaces, testing, and warranty boundaries only. Commercial risk allocation, financing structures, delivery arrangements, and lender requirements are addressed in separate contractual documents.
Manufacturing Classification
This document describes module-level requirements for an Advanced Circular Manufacturing subsystem and does not define or imply waste treatment, storage, or disposal activities.
Near-Zero Design Intent
The Zero-E PowerBlock™ system is engineered as a closed-loop manufacturing subsystem designed for near-zero emissions, near-zero discharge, and near-zero residual through enclosed material handling, continuous negative-pressure operation, internal capture via the APS Capture Stream, and absence of routine discharge pathways. Environmental performance validated at SAT and FPT.
ASI Role Statement
Carbotura Inc. holds all design authority, engineering specifications, and OEM intellectual property. The Authorized Strategic Integrator (ASI) — vendor to be selected per D-ASI-01 — is responsible for packaging design, system integration, fabrication, factory assembly, Factory Acceptance Testing (FAT), quality assurance, third-party certifications, Unitized Warranty Passport issuance, and authorized spares provisioning, all executed to Carbotura OEM specification. The ASI holds no design authority. All engineering changes require Carbotura ECN authorization prior to ASI implementation.
American Manufacturing Preference
All Carbotura ACM Facility modules are assembled, tested, and warranted in the United States of America by the ASI. Equipment procurement adheres to Carbotura's American Manufacturing Preference Policy supporting DOE LPO domestic content requirements, Buy American Act alignment, and institutional investor supply chain transparency obligations.
Revenue Performance Baseline
All throughput guarantees and performance metrics baselined to RevCon 3: $150M–$325M/yr revenue floor at 400 TPD baseline factory configuration (128 PEM modules / 32 MW Zero-E PowerBlock / 10 Regenesis-REGMAX modules / one Pregenesis module at full nameplate throughput).
The Zero-E PowerBlock™ is the Carbotura-branded integrated power generation system that provides islanded, grid-independent electrical power to all ACM Facility loads. It comprises 128 point-of-use PEM Fuel Cell modules (at 400 TPD canonical basis), a facility-level Battery Energy Storage System (BESS), localized Supercapacitor banks at each PEM module, distributed hydrogen delivery infrastructure, a three-tier Nested DC distribution topology, and the Zero-E Thermal Recovery Stream collection loop. Hydrogen is the primary facility energy carrier. Electricity is generated at the point of consumption — not distributed from a central power house.
The Zero-E PowerBlock™ is a Carbotura OEM product specification. It is a serial-numbered, factory-assembled, FAT-tested system executed by the ASI. It delivers 8 MW per 100 TPD processing increment, scaling linearly to 32 MW at the 400 TPD canonical engineering baseline and 80 MW at the 1,000 TPD Single-Building Maximum configuration.
2. Facility Context & Module Boundaries
2.1 System Position in the ACM Facility
The Zero-E PowerBlock™ is the sole source of electrical power for the ACM Facility. It operates in islanded mode — no utility grid connection is required or relied upon for normal operation. Grid connection, if present, is an Owner option for commissioning and black start backup only.
| Parameter | Value |
|---|
| Building scope | PIMB (Pregenesis loads) and RMB (Regenesis loads) — both served from the shared Zero-E PowerBlock |
| Distribution architecture | Point-of-use: PEM modules co-located with load centers in both buildings |
| Interface to NEXUS | MVDC Backbone feeds into NXS-Z1; receives H₂ from NXS-Z3; delivers Zero-E Thermal Recovery Stream to NXS-Z2 |
| Canonical basis | 400 TPD / 128 PEM modules / 32 MW output |
2.2 Module Boundaries
| Module | Tag | Upstream Boundary | Downstream Boundary |
|---|
| PEM Fuel Cell Module | ZEP-PEM-001 to -128 | H₂ supply at NXS-Z3 zone drop (dual-stage regulator inlet) | 800V DC at ASI-PBK-QC device link connector |
| Battery Energy Storage System | ZEP-BSS-001 | MVDC Backbone bus connection | MVDC Backbone bus — grid-forming / Black Start output |
| Supercapacitor Bank (per PEM) | ZEP-SCB-001 to -128 | PEM module 800V DC output | Parallel load bus at device link |
| MVDC Backbone | ZEP-MVB-001 | PEM module aggregation point (via zone bus) | All facility-level load centers at 20kV MVDC ECN pending 30kV |
| Zone Bus Segment | ZEP-ZBS-001 to -004 | 1,500V DC aggregation from 32 PEM modules per zone | 20kV MVDC via DC/DC step-up |
| H₂ Regulation Station | ZEP-H2R-001 to -004 | NXS-Z3 H₂ header at zone drop (high-pressure) | Intermediate pressure (~20 bar — D-H2-01 parametric) to PEM module skids |
| DC/AC Inverter | ZEP-INV-001 to -016 | 800V DC device link (skid-local, per reactor) | 480V AC at magnetron transformer primary |
| Zero-E Thermal Recovery Loop | ZEP-TRL-001 | PEM module coolant outlet (water-glycol, 85–95°C) | ASI-THM-ZE connector → NXS-Z2-FLUID low-temp header |
2.3 Excluded Scope
| Item | Boundary | Governing Document |
|---|
| NXS-Z1 overhead routing spine | NEXUS scope — ZEP delivers to NXS-Z1 interface point | CBT-NXS-TDS-001 |
| NXS-Z3 H₂ header and storage | NEXUS scope — ZEP receives from NXS-Z3 drop | CBT-NXS-TDS-001 |
| REG-BSH-001 H₂ buffer storage vessel | Regenesis Protocol scope | CBT-REG-TDS-001 Rev 1 |
| Utility grid interconnect | Owner scope — not required for normal operation | — |
| 48V DC controls bus | Open — D-48V-01 (OER Gate 2) | D-48V-01 |
| SCADA software | Owner scope — Modbus TCP interface defined in §7 | — |
| APS main collection header | APS Protocol scope | CBT-APS-TDS-001 |
3. Process Description
3.1 Narrative Overview
The Zero-E PowerBlock™ operates on the following energy conversion sequence: hydrogen gas produced by the Regenesis Protocol is stored in REG-BSH-001 and distributed to the facility via NXS-Z3 at high pressure. At each zone, ZEP-H2R-001 through -004 regulate pressure from the NXS-Z3 header to an intermediate pressure for local distribution to PEM module skids. Each PEM module skid contains a second-stage regulator that reduces pressure to the PEM fuel cell stack operating pressure. The PEM fuel cell stack electrochemically oxidizes H₂ to produce 800V DC power and a water-glycol thermal output at 85–95°C. Multiple PEM module outputs aggregate through Supercapacitor banks to the 1,500V zone bus. Four zone bus segments aggregate to the 20kV MVDC Backbone. The MVDC Backbone distributes power facility-wide. The facility-level BESS (ZEP-BSS-001) provides Black Start capability, grid-forming voltage reference, and facility-level transient buffering. Skid-local DC/AC inverters (ZEP-INV-001 to -016) convert 800V DC device-link power to 480V AC for magnetron transformer inputs.
3.2 Process Flow
| Step | Stage | Equipment | Input | Output |
|---|
| 1 | H₂ Zone Regulation | ZEP-H2R-001 to -004 | NXS-Z3 H₂ header (high-pressure — D-H2-01) | Intermediate pressure H₂ ~20 bar (D-H2-01 parametric) |
| 2 | H₂ Stack Regulation | PEM skid local regulator | Intermediate H₂ ~20 bar | Stack inlet pressure (OEM-specified at RFQ) |
| 3 | PEM Electrochemical Conversion | ZEP-PEM-001 to -128 | H₂ + ambient O₂ | 250 kW DC at 800V │ Thermal output at 85–95°C │ Product water |
| 4 | Transient Buffering | ZEP-SCB-001 to -128 | PEM 800V DC output | Buffered 800V DC — absorbs inrush up to 120% rated load |
| 5 | Zone Aggregation | ZEP-ZBS-001 to -004 | 32 × 800V DC inputs per zone | 1,500V DC zone bus │ 8 MW per zone |
| 6 | Backbone Distribution | ZEP-MVB-001 | 4 × 1,500V zone inputs | 20kV MVDC facility backbone |
| 7 | AC Conversion (Magnetron Loads) | ZEP-INV-001 to -016 | 800V DC device link | 480V AC │ 750 kW per inverter |
| 8 | Thermal Recovery | ZEP-TRL-001 | PEM coolant at 85–95°C | Zero-E Thermal Recovery Stream → NXS-Z2-FLUID |
| 9 | Black Start / Grid-Forming | ZEP-BSS-001 | Stored energy (BESS) | Grid-forming 20kV MVDC reference at facility start |
3.3 Energy Balance — 400 TPD Canonical Basis
| Parameter | Value | Basis |
|---|
| Total Zero-E PowerBlock output | 32 MW | 128 × 250 kW — ARM-2026-002 §3.4 |
| Magnetron load (16 reactors × 720 kW AC draw) | 11.52 MW | D-30 LOCKED Session 5 |
| Available NXS-Z1 balance (non-magnetron loads) | ≤20.48 MW | 32 MW − 11.52 MW |
| Zero-E Thermal Recovery Stream output | 85–95°C water-glycol closed loop | ARM-2026-002 Cluster G |
| PEM module H₂ consumption (per module, 250 kW) | ~5.0–5.8 kg H₂/hr (parametric — D-H2-01) | PEM efficiency ~50–58% LHV basis — OER Gate 2 OEM confirmation |
| Total facility H₂ consumption (128 modules, 400 TPD) | ~640–742 kg H₂/hr parametric | OER Gate 2 OEM confirmation |
| BESS capacity (Black Start, minimum) | 1 MW / capacity sufficient for Stage 1–2 Black Start sequence | ARM-2026-002 §4.2 |
3.4 Scaling Table
| Configuration | TPD | PEM Modules | Zero-E Output | Zone Bus Segments | DC/AC Inverters |
|---|
| 100 TPD Minimum Factory Module | 100 | 32 | 8 MW | 1 | 4 |
| 200 TPD | 200 | 64 | 16 MW | 2 | 8 |
| 300 TPD | 300 | 96 | 24 MW | 3 | 12 |
| 400 TPD (Canonical Baseline) | 400 | 128 | 32 MW | 4 | 16 |
| 1,000 TPD Single-Building Maximum | 1,000 | 320 | 80 MW | 10 | 40 |
4. H₂ Feedstock Design Envelope
For CBT-ZEP-TDS-001, "feedstock" is the H₂ supply delivered to the Zero-E PowerBlock via NXS-Z3 from REG-BSH-001.
4.1 H₂ Supply Specification
| Parameter | P50 Design Basis | P90 Envelope | Status |
|---|
| H₂ purity | ≥99.97% — ISO 14687 Type D (fuel cell grade) | ≥99.95% minimum — below this PEM stack degradation begins | OER Gate 2 — PEM OEM to confirm |
| Supply pressure at NXS-Z3 header | D-H2-01 OPEN — 20–50 bar parametric | OPEN — D-H2-01 | OER Gate 2 |
| Supply temperature | Ambient (15–40°C) | 5–50°C operating range | OER Gate 2 OEM confirmation |
| H₂O content | ≤5 ppm | ≤10 ppm (P90) | ISO 14687 — PEM OEM spec governs |
| O₂ content | ≤5 ppm | ≤10 ppm | ISO 14687 |
| Total sulfur | ≤4 ppb | ≤10 ppb — stack contamination threshold | ISO 14687 — critical stack life parameter |
| Supply continuity | Continuous — no batch cycles | ≥95% supply uptime from REG-BSH-001 | REG-BSH-001 buffer sizing governs — D-29 open |
4.2 Prohibited Supply Conditions
| Condition | Consequence | Interlock Response |
|---|
| H₂ purity below 99.95% | Stack membrane contamination — irreversible degradation | SCADA alarm + isolate affected ZEP-PEM modules; HVIL activates |
| Sulfur content >10 ppb | Catalyst poisoning — permanent stack damage | Immediate PEM isolation — maintenance hold |
| Supply pressure below minimum regulation range | PEM under-pressure fault — output derate or shutdown | HVIL fail-closed at ZEP-H2R zone drop |
| Supply interruption >BESS autonomy duration | Facility power loss — Black Start sequence required | Stage 1 BESS activation per §5.3 Black Start protocol |
Guarantee Conditionality Statement
All Zero-E PowerBlock™ performance guarantees apply when H₂ supply meets P50 design specification at the NXS-Z3/ZEP-H2R interface. If H₂ supply is outside the P90 envelope, performance guarantees are suspended at that interface per the Unitized Warranty Passport boundary conditions.
5. Module Equipment Specifications
5.1 ZEP-PEM-001 to -128 — PEM Fuel Cell Modules (128 per 400 TPD)
| Parameter | Value | Status |
|---|
| Function | Electrochemical conversion of H₂ to DC electrical power at point of use. Co-located with load center. No central power house. | LOCKED — ARM-2026-002 Cluster B |
| Rated output per module | 250 kW DC | LOCKED — ARM-2026-002 §3.3 |
| Output voltage | 800V DC | LOCKED — ARM-2026-002 Cluster A |
| Output connector | Amphenol ePower-Lite — ASI-PBK-QC | LOCKED — D-HVDC-01 |
| HVIL circuit | Integrated — H₂ supply fail-closed valve activation <50 ms on HVIL break | LOCKED — ARM-2026-002 §2.3 |
| Module count at 400 TPD | 128 (32 per 100 TPD zone) | LOCKED |
| H₂ feed regulation | Dual-stage: zone header (~20 bar, D-H2-01) → stack inlet pressure at PEM skid via digital mass flow controller | LOCKED |
| Coolant output | Water-glycol closed loop — 85–95°C — Zero-E Thermal Recovery Stream | LOCKED — Cluster G |
| Installation | Skid-mounted; co-located with load center; <3 m device link runs | LOCKED |
| Stack design life | ≥40,000 hours continuous operation target | OER Gate 2 OEM confirmation |
| Duty cycle | Continuous at rated load; capacity factor ≥92% | OER Gate 2 OEM confirmation |
| APS interface | H₂ purge gas from PEM enclosure → APS-ZEP-001 → NXS-Z3 recycle | D-ZEP-APS-01 CLOSED |
| CAPEX per module | $250K–$800K parametric [Class 2 ±15%, 2026 USD] | Parametric — OER Gate 2 |
| CAPEX — 128 modules, 400 TPD | $32.0M–$102.4M parametric | — |
5.2 ZEP-BSS-001 — Battery Energy Storage System (1 per facility)
| Parameter | Value | Status |
|---|
| Function | Facility-level grid-forming voltage reference; Black Start Stage 1 cold-start energy source; facility-wide transient buffering at MVDC level | LOCKED — Cluster C |
| Minimum rated capacity | 1 MW Black Start BESS — capacity sufficient for Black Start Stages 1 and 2 | LOCKED — ARM-2026-002 §4.2 |
| Energy capacity | 500 kWh–2 MWh parametric; sufficient for Stage 1 + Stage 2 sequence | OER Gate 2 OEM sizing |
| Technology | LFP (lithium iron phosphate) preferred — thermally stable; no thermal runaway propagation risk; US-manufactured preferred | OER Gate 2 OEM selection |
| Grid-forming mode | Active at all times during normal facility operation — provides voltage reference for MVDC Backbone | LOCKED |
| Connection | MVDC Backbone — 20kV MVDC bus via DC/DC bidirectional converter | LOCKED |
| Safety | LFP cell chemistry. Fire suppression integrated (OEM scope). H₂ off-gas monitoring at enclosure. Vent to APS-ZEP-002. | §6 |
| CAPEX | $800K–$3.0M parametric [Class 2 ±15%, 2026 USD] | Parametric |
5.3 Black Start Protocol — Four-Stage Sequence
| Stage | Label | Action | Status |
|---|
| 1 | Cold Start | ZEP-BSS-001 energizes MVDC Backbone. Powers H₂ extraction/circulation pumps, gas sensing systems, SCADA, and safety systems. | LOCKED — §4.3 |
| 2 | Ignition | First 250 kW PEM module (ZEP-PEM-001) comes online; claims local 800V device bus; begins H₂ consumption from REG-BSH-001 | LOCKED |
| 3 | Zone Bootstrap | PEM modules in Zone 1 come online sequentially; ZEP-ZBS-001 energizes; Zone 1 loads released from BESS to PEM supply | LOCKED |
| 4 | Full Power | All 128 PEM modules at rated load; ZEP-BSS-001 shifts from Black Start mode to Grid-Forming steady-state; facility at full power | LOCKED |
5.4 ZEP-SCB-001 to -128 — Supercapacitor Banks (1 per PEM module)
| Parameter | Value | Status |
|---|
| Function | Transient inrush buffering at each PEM module; absorbs load inrush up to 120% of rated module output | LOCKED |
| Sizing | 120% of peak inrush current at each 250 kW module | OER Gate 2 |
| Configuration | Wired in parallel with PEM module output at 800V device bus | LOCKED |
| Technology | EDLC (electrochemical double-layer capacitor) — high cycle life, no thermal runaway | OER Gate 2 OEM selection |
| CAPEX per bank | $8K–$25K parametric | Parametric |
| CAPEX — 128 banks, 400 TPD | $1.0M–$3.2M parametric | — |
5.5 ZEP-ZBS-001 to -004 — Zone Bus Segments (4 per 400 TPD)
| Parameter | Value | Status |
|---|
| Function | 8 MW zone aggregation from 32 PEM modules; provides 1,500V DC zone bus | LOCKED |
| Voltage | 1,500V DC | LOCKED |
| Current capacity | 5,300A in 19-in. rack width | LOCKED — §2.2 |
| Busbar type | Liquid-cooled laminated busbars | LOCKED — §4.2 |
| Connector | Stäubli MPC (MULTILAM contacts) — ASI-ZBK-MPC | LOCKED |
| CAPEX — 4 segments, 400 TPD | $2.4M–$7.2M parametric | — |
5.6 ZEP-MVB-001 — MVDC Backbone (1 per facility)
| Parameter | Value | Status |
|---|
| Function | Building-wide energy balancing; BESS link; inter-zone synchronization; facility-level power routing | LOCKED |
| Voltage | 20kV MVDC ECN pending — Session 9 correction to 30kV | LOCKED at Rev 0 / ECN pending |
| Connector | HARTING Han® HPR — ASI-MVDC-HPR | LOCKED |
| Physical routing | NXS-Z1 overhead spine — Backbone routing is NEXUS scope; ZEP scope is generation and aggregation | CBT-NXS-TDS-001 |
| CAPEX | $1.5M–$5.0M parametric | Parametric |
5.7 ZEP-H2R-001 to -004 — H₂ Regulation Stations (4 per 400 TPD)
| Parameter | Value | Status |
|---|
| Function | First-stage H₂ pressure regulation from NXS-Z3 high-pressure header to intermediate distribution pressure | LOCKED |
| Inlet pressure | NXS-Z3 H₂ header | OPEN — D-H2-01 (20–50 bar parametric) |
| Outlet pressure | ~20 bar intermediate — D-H2-01 parametric | OER Gate 2 |
| Safety interlock | Pneumatic fail-closed isolation valve; HVIL-linked; H₂ isolation <50 ms on HVIL break | LOCKED |
| Gas detection | Point H₂ gas detector; alarm at 10% LFL; auto-isolation at 25% LFL | OER Gate 2 |
| CAPEX — 4 stations, 400 TPD | $400K–$1.4M parametric | — |
5.8 ZEP-INV-001 to -016 — DC/AC Inverters (16 per 400 TPD)
| Parameter | Value | Status |
|---|
| Function | Skid-local conversion of 800V DC device-link power to 480V AC for magnetron transformer primary input | LOCKED — D-AC-01 Session 5 |
| Rated capacity | 750 kW per inverter | LOCKED |
| Input voltage | 800V DC (device link) | LOCKED |
| Output | 480V AC, 3-phase — magnetron transformer primary | LOCKED |
| Quantity at 400 TPD | 16 (one per reactor) | LOCKED — D-AC-01, D-37 |
| CAPEX — 16 inverters | $2.4M–$7.2M parametric | — |
5.9 ZEP-TRL-001 — Zero-E Thermal Recovery Loop (1 per facility)
| Parameter | Value | Status |
|---|
| Function | Collects PEM module coolant output (water-glycol, 85–95°C) across all 128 modules; delivers as Zero-E Thermal Recovery Stream to NXS-Z2-FLUID | LOCKED — Cluster G |
| Coolant medium | Water-glycol closed loop | LOCKED |
| Temperature | 85–95°C | LOCKED |
| Interface | ASI-THM-ZE — Zero-E Thermal Recovery connector → NXS-Z2-FLUID low-temp header | DEFINED — Cluster G |
| Downstream use | Facility heating, feedwater pre-heating, or Owner-scope thermal load — NOT primary thermal supply to T2-ITD or PRE-EVP-001 (those receive WHSG High-Temperature Thermal Recovery) | Cluster G |
| CAPEX | $300K–$900K parametric | Parametric |
6. APS Interface Register
APS Process-Capture Basis
CFM figures are process-capture basis only. No dilution air, comfort ventilation, or regulatory dispersion airflow is included. All APS Capture Stream flows represent product streams being recovered or contaminated air managed internally. APS system design is specified in CBT-APS-TDS-001.
| APS Point | Tag | Source | Normal CFM | Peak CFM | Recovery Value | Status |
|---|
| PEM enclosure H₂ purge vent | APS-ZEP-001 | ZEP-PEM module enclosures — H₂ purge gas and incidental off-gas | 50–120 CFM (aggregate, 128 modules) | 400 CFM (max purge event) | Recovered H₂ → NXS-Z3 recycle header. No flare. All H₂ purge gas is a recoverable energy stream returned to NXS-Z3 for reuse. | DEFINED — D-ZEP-APS-01 CLOSED |
| BESS enclosure battery off-gas vent | APS-ZEP-002 | ZEP-BSS-001 battery enclosure — LFP off-gas during charging or fault | 20–40 CFM normal | 200 CFM fault event | Safety stream — no recovery value | DEFINED |
Note: The Zero-E PowerBlock™ is primarily an electrical system. APS capture requirements are limited to H₂ purge ventilation and BESS off-gas management. H₂ purge gas (APS-ZEP-001) routes to NXS-Z3 recycle — recoverable energy stream, not disposal. BESS off-gas (APS-ZEP-002) is a safety capture. The dominant APS loads in the ACM Facility are from Pregenesis and Regenesis process modules.
7. Modular Installability & Interface Control
SAT/FPT Statement
Site Acceptance Testing (SAT) and Full Performance Testing (FPT) will be conducted following module assembly and initial startup. SAT verifies correct assembly and individual equipment function. FPT verifies integrated performance against guaranteed parameters. A 72-hour continuous Throughput Performance Guarantee Test (TPGT) is required with H₂ supply within the P90 envelope, witnessed by Carbotura Engineering, Owner's Engineer, and an independent third party.
| ICD Reference | Interface Description | Connection Type | ASI Standard | Status |
|---|
| ICD-ZEP-PEM-PWR-001 | ZEP-PEM module 800V DC output → device link bus | 800V DC, Amphenol ePower-Lite, <3 m runs | ASI-PBK-QC | DEFINED |
| ICD-ZEP-ZBS-001 | Zone Bus → MVDC Backbone (per zone) | 1,500V DC liquid-cooled laminated busbar | ASI-ZBK-MPC | DEFINED |
| ICD-ZEP-MVB-001 | MVDC Backbone → facility load distribution | 20kV MVDC, HARTING Han® HPR | ASI-MVDC-HPR | DEFINED — ECN pending 30kV |
| ICD-ZEP-H2-001 | NXS-Z3 H₂ header → ZEP-H2R zone regulation station | High-pressure H₂ pipe — ANSI 600# RF (parametric pending D-H2-01) | ASI-H2-HPS | OPEN — D-H2-01 |
| ICD-ZEP-BSS-001 | ZEP-BSS-001 → MVDC Backbone | 20kV MVDC bidirectional DC/DC | ASI-MVDC-HPR | DEFINED |
| ICD-ZEP-TRL-001 | ZEP-TRL-001 Zero-E Thermal Recovery → NXS-Z2-FLUID low-temp header | Water-glycol pipe — 316L SS | ASI-THM-ZE | DEFINED |
| ICD-ZEP-INV-001 | ZEP-INV (per reactor) 800V DC input → 480V AC magnetron transformer primary | 800V DC device link + 480V AC output | ASI-PBK-QC / Hardwire | DEFINED — D-AC-01 |
| ICD-ZEP-SCADA-001 | ZEP power management system → Facility SCADA | Modbus TCP over shielded Cat6A | ASI-DAT-MOD-TCP | DEFINED |
| ICD-ZEP-APS-001 | PEM enclosure H₂ purge vent → NXS-Z3 recycle header | APS duct flange to NXS-Z3 recycle inlet | ASI-APS-FLG | DEFINED — D-ZEP-APS-01 CLOSED |
8. Utilities Register
The Zero-E PowerBlock™ is the primary utilities provider for the ACM Facility. This section records utilities consumed BY the Zero-E PowerBlock itself during operation — not utilities it delivers.
8.1 NXS-Z1-ELEC — Electrical (Consumed by ZEP Internal Systems)
| Load | Tag | kW (P50) | kW (P90) | Notes |
|---|
| BESS parasitic (BMS, cooling, controls) | ZEP-BSS-001 | 15 kW | 25 kW | Internal BESS load — drawn from MVDC Backbone |
| H₂ regulation station controls | ZEP-H2R-001 to -004 | 2 kW | 5 kW | Valve actuators, instrumentation, gas detection |
| Zero-E Thermal Recovery Loop pump | ZEP-TRL-001 | 10 kW | 20 kW | Coolant circulation — 128 modules |
| 48V DC controls bus (ZEP scope) | D-48V-01 | OPEN | OPEN | D-48V-01 — OER Gate 2 |
| Total ZEP internal electrical consumption | | ~27 kW | ~50 kW | Negligible vs. 32 MW generation |
8.2 NXS-Z3-GAS — H₂ Supply (Primary Input)
| Parameter | P50 | P90 | Notes |
|---|
| H₂ consumption — 128 modules | 640–742 kg/hr | 742–820 kg/hr (derate) | Basis: ~50–58% LHV efficiency; OER Gate 2 |
| Supply pressure | D-H2-01 OPEN | D-H2-01 OPEN | OER Gate 2 |
| H₂ purity required | ≥99.97% ISO 14687 Type D | ≥99.95% minimum | §4.1 |
8.3 NXS-Z2-FLUID — Thermal (Delivered BY ZEP)
| Parameter | Value | Notes |
|---|
| Zero-E Thermal Recovery Stream output | 85–95°C water-glycol | Delivered to NXS-Z2-FLUID low-temp header |
| Thermal quantity | ~1.5–3.0 MW thermal (parametric) | Varies by load factor and ambient; OER Gate 2 OEM cooling load |
9. Vendor Matrix
American Manufacturing Preference — ARM-2026-002 Cluster H
US-domiciled OEMs preferred. All compliance status is preliminary — verification required at RFQ stage.
| Equipment | Vendor | Country | Procurement | Lead Time |
|---|
| PEM Fuel Cell Module (250 kW) | Plug Power Inc. | USA (Latham, NY) | Direct — US | 30–52 wks |
| PEM Fuel Cell Module (250 kW) | Cummins Inc. (Hydrogenics) | USA (Fridley, MN) | Direct — US | 26–48 wks |
| PEM Fuel Cell Module (250 kW) | Ballard Power Systems | Canada | ASI-Integrated | 30–52 wks |
| BESS — LFP (1–2 MWh) | Powin Energy | USA (Portland, OR) | Direct — US | 20–36 wks |
| BESS — LFP (1–2 MWh) | Saft (TotalEnergies) | USA (Valdosta, GA) | Direct — US | 24–40 wks |
| Supercapacitor Banks | Kyocera AVX (Maxwell) | USA (Fountain Inn, SC) | Direct — US | 12–20 wks |
| Supercapacitor Banks | KEMET Electronics (Yageo) | USA (Greenville, SC) | Direct — US | 10–18 wks |
| Liquid-Cooled Zone Busbars | Mersen USA | USA (Greenville, SC) | Direct — US | 20–32 wks |
| Liquid-Cooled Zone Busbars | Methode Electronics | USA (Chicago, IL) | Direct — US | 18–30 wks |
| MVDC Switchgear / Backbone | Eaton Corporation | USA (Pittsburgh, PA) | Direct — US | 30–52 wks |
| MVDC Switchgear / Backbone | ABB Ltd. | USA (Cary, NC) | Direct — US | 28–48 wks |
| H₂ Regulation Stations | Emerson (Fisher Controls) | USA (Marshalltown, IA) | Direct — US | 16–28 wks |
| H₂ Regulation Stations | Parker Hannifin | USA (Cleveland, OH) | Direct — US | 14–26 wks |
| DC/AC Inverters (750 kW) | SMA America | USA (Rocklin, CA) | Direct — US | 20–32 wks |
| DC/AC Inverters (750 kW) | Siemens Energy | USA (Wendell, NC) | Direct — US | 20–36 wks |
9.1 Excluded Vendors — Preliminary INELIGIBLE
| Vendor | Reason | Authority |
|---|
| CATL, BYD, SVOLT (BESS) | China-domiciled manufacturer | ARM-2026-002 §9.2 — pending compliance verification |
| Huawei (Inverters) | China-domiciled — ITAR/BIS concern | ARM-2026-002 §9.2 |
INELIGIBLE designation is preliminary pending verified documentation per ARM-2026-002 §9.3.
10. CAPEX Estimate
| Line Item | Low | High | Basis |
|---|
| ZEP-PEM-001 to -128 — PEM Fuel Cell Modules (128 units) | $32.0M | $102.4M | $250K–$800K per unit |
| ZEP-BSS-001 — BESS (1–2 MWh, LFP) | $0.8M | $3.0M | Commercial LFP BESS market |
| ZEP-SCB-001 to -128 — Supercapacitor Banks | $1.0M | $3.2M | $8K–$25K per bank |
| ZEP-ZBS-001 to -004 — Zone Bus Segments (liquid-cooled) | $2.4M | $7.2M | $600K–$1.8M per zone segment |
| ZEP-MVB-001 — MVDC Backbone Switchgear | $1.5M | $5.0M | Industrial MVDC — 32 MW basis |
| ZEP-H2R-001 to -004 — H₂ Regulation Stations | $0.4M | $1.4M | Industrial H₂ pressure regulation |
| ZEP-INV-001 to -016 — DC/AC Inverters (16 units, 750 kW) | $2.4M | $7.2M | $150K–$450K per inverter |
| ZEP-TRL-001 — Zero-E Thermal Recovery Loop | $0.3M | $0.9M | Piping, pumps, manifold |
| E&I — Electrical and Instrumentation | $2.0M | $5.0M | 5–8% of equipment subtotal |
| ASI Integration, Assembly, FAT | $3.0M | $8.0M | 8–10% of equipment subtotal |
| Contingency (15%) | $6.9M | $21.5M | AACE Class 2 — 15% |
| Total Module CAPEX — 400 TPD | $52.7M | $164.8M | [Class 2 ±15%, 2026 USD] |
| Per 100 TPD scaling increment | $13.2M | $41.2M | Linear scaling |
AACE Classification: Class 2 ±15% — 2026 USD basis. OER Gate 2 OEM quotes required. CAPEX range will narrow significantly upon PEM module OEM selection (dominant line item at 61–62% of total).
Included: All ZEP-tagged equipment, E&I, ASI assembly and FAT, Unitized Warranty Passport.
Excluded: NXS-Z1 overhead routing spine (NEXUS scope), REG-BSH-001 H₂ buffer storage (Regenesis scope), site civil works, Owner's contingency, financing costs, owner's costs.
11. TIC WBS Reconciliation
| WBS Item | In Module CAPEX | Notes |
|---|
| PEM module equipment and factory assembly | ✅ | Per §10 |
| BESS equipment and integration | ✅ | — |
| SuperCap banks — factory installed per PEM skid | ✅ | — |
| Zone bus segments — factory assembled | ✅ | — |
| MVDC backbone switchgear | ✅ | — |
| H₂ regulation stations | ✅ | — |
| DC/AC inverters — skid-local per reactor | ✅ | — |
| Zero-E Thermal Recovery Loop — piping and pumps | ✅ | — |
| E&I (ZEP scope) | ✅ | — |
| ASI Factory Acceptance Testing (FAT) | ✅ | — |
| Unitized Warranty Passport | ✅ | — |
| NXS-Z1 routing spine | ❌ | NEXUS scope — CBT-NXS-TDS-001 |
| NXS-Z3 H₂ header (backbone routing) | ❌ | NEXUS scope |
| REG-BSH-001 H₂ buffer | ❌ | Regenesis scope |
| Site foundations and slab preparation | ❌ | Owner scope — standard flat slab; no precision cuts required |
| Utility grid connection (if Owner-elected) | ❌ | Owner scope |
| SCADA software licensing | ❌ | Owner scope |
All-in TIC estimate (ZEP scope only, 400 TPD): $52.7M–$164.8M [Class 2 ±15%, 2026 USD]. The PEM module cost is the dominant TIC driver. OER Gate 2 OEM quote from minimum two US-domiciled vendors is the single highest-leverage action for TIC accuracy improvement.
12. Lead Time Schedule
Critical Path
PEM modules and MVDC Backbone switchgear are co-critical at 30–52 weeks. D-ASI-01 (ASI selection) is the prerequisite to issuing any PEM or MVDC RFQ. All lead times are contingent on D-ASI-01 closure.
| Equipment | Tag | Lead Time | Critical Path? | Notes |
|---|
| PEM Fuel Cell Modules (128 units) | ZEP-PEM-001 to -128 | 30–52 wks | 🔴 YES | Largest quantity; volume OEM negotiation may compress. Batch ordering required. |
| MVDC Backbone Switchgear | ZEP-MVB-001 | 30–52 wks | 🔴 YES | Custom MVDC ratings; limited US OEM base |
| BESS (1–2 MWh LFP) | ZEP-BSS-001 | 20–40 wks | 🟡 Float ~10 wks | Standard commercial product |
| Zone Bus Segments (liquid-cooled) | ZEP-ZBS-001 to -004 | 20–32 wks | 🟡 Float ~10 wks | Custom liquid-cooled design |
| DC/AC Inverters (16 units) | ZEP-INV-001 to -016 | 20–36 wks | 🟡 Float ~10 wks | Standard industrial product; 750 kW class |
| H₂ Regulation Stations | ZEP-H2R-001 to -004 | 14–28 wks | 🟢 Float ~20 wks | Standard pressure regulation equipment |
| SuperCap Banks (128 units) | ZEP-SCB-001 to -128 | 12–20 wks | 🟢 Float ~25 wks | Standard EDLC product |
| ZEP Thermal Recovery Loop piping | ZEP-TRL-001 | 16–26 wks | 🟢 Float | Standard 316L SS piping |
Module Delivery Schedule milestone: First module delivery target is 52 weeks from D-ASI-01 closure and NTP issuance. Full 128-module delivery at 60–72 weeks from NTP.
13. TRL / ERL / IRL Assessment
| Equipment | TRL | ERL | IRL | Notes |
|---|
| PEM Fuel Cell Modules (250 kW) | 8 | 7 | 6 | Commercially deployed at scale. Integration into Carbotura Nested DC topology is novel but interfaces well-defined. IRL limited by D-ASI-01 and D-H2-01. |
| BESS — LFP | 9 | 8 | 7 | Fully commercial. Grid-forming mode standard for modern BMS. |
| Supercapacitor Banks | 9 | 8 | 7 | Fully commercial EDLC. Integration at PEM module level straightforward. |
| Nested DC Topology (20kV MVDC) | 7 | 6 | 5 | 20kV MVDC at facility scale less common than lower-voltage microgrids. Industrial precedent exists (offshore, mining). |
| Zone Bus (1,500V Liquid-Cooled) | 8 | 7 | 6 | Liquid-cooled laminated busbars at 1,500V commercially available. |
| DC/AC Inverters (750 kW) | 9 | 8 | 7 | Fully commercial. Skid-local per reactor is established architecture. |
| H₂ Regulation Stations | 9 | 8 | 6 | Commercial high-pressure gas regulation. IRL limited by D-H2-01. |
| Zero-E Thermal Recovery Loop | 8 | 7 | 6 | Standard heat exchanger and piping. Temperature range (85–95°C) is low-risk. |
| System-Level Zero-E PowerBlock | 7 | 6 | 5 | System TRL limited by Nested DC topology novelty at scale. IRL limited by D-ASI-01 and D-H2-01. |
14. Confidence Factor
| Dimension | Weight | Score (1–5) | Weighted | Basis |
|---|
| Technology maturity (PEM, BESS, busbars) | 25% | 4.2 | 1.05 | All major components commercially deployed |
| Interface definition completeness | 20% | 3.5 | 0.70 | D-H2-01 and D-48V-01 open; others defined |
| Vendor availability (US market) | 15% | 4.0 | 0.60 | Strong US PEM/BESS market; MVDC narrower |
| CAPEX basis quality | 20% | 2.5 | 0.50 | No OEM quotes; parametric only; PEM range wide |
| Open decision exposure | 10% | 3.0 | 0.30 | D-H2-01, D-48V-01, D-ASI-01 — all procurement scope |
| Scaling precedent | 10% | 3.8 | 0.38 | 128-module PEM arrays exist; 20kV MVDC less common at scale |
| Total Confidence Factor | 100% | | 3.53 / 5.00 (71%) | Class 2 working document at first release |
Interpretation: Consistent with Class 2 working document at first release — underlying technology commercially mature, OEM quotes not yet received, two OER Gate 2 decisions remain open. Primary confidence limiter is CAPEX basis quality (no OEM quotes) and 20kV MVDC novelty at facility scale. Confidence factor will increase significantly at OER Gate 2 upon PEM module and MVDC OEM quote receipt and D-ASI-01 closure.
15. Availability Model
Guarantee Conditionality
All throughput, performance, and availability guarantees apply when: (1) H₂ supply is within P90 design envelope per §4; (2) utilities per §8; (3) operation follows OPS procedures; (4) Planned Maintenance Intervals adhered to per §17; (5) ASI has completed FAT and issued Unitized Warranty Passport.
15.1 Equipment-Level Availability
| Equipment | MA (%) | MTBF (hrs) | MTTR (hrs) | Notes |
|---|
| PEM Module (per unit) | 97–99 | 40,000+ | 4–8 | Stack replacement on degradation; swap time skid-local |
| PEM Array — 128 modules, N+1 | ≥99.5 | — | — | Any single module fault absorbed by reserve capacity |
| BESS (ZEP-BSS-001) | 98–99 | 15,000+ | 8–16 | LFP cell degradation; BMS diagnostic-driven maintenance |
| Zone Bus Segments | 99.5+ | 50,000+ | 4–8 | Liquid cooling failures rare; laminated busbars long-life |
| MVDC Backbone switchgear | 99.5+ | 50,000+ | 8–16 | Industrial-grade equipment; periodic inspection |
| DC/AC Inverters (per reactor) | 98–99 | 30,000+ | 4–8 | Standard industrial inverter reliability |
| Zero-E PowerBlock System OA | ≥99.2% | — | — | Redundancy throughout; no single point of failure for critical loads |
16. Risk Register
| Risk ID | Description | Severity | Mitigation |
|---|
| R-01 | D-ASI-01 Open — ASI Vendor Not Selected | HIGH | No PEM or MVDC RFQ can be issued until D-ASI-01 closes. Competitive RFQ to ≥3 qualified ASI candidates per ARM-2026-002 American Manufacturing Preference Policy. |
| R-02 | D-H2-01 Open — H₂ Header Pressure Undefined | HIGH | Close D-H2-01 at OER Gate 2 with H₂ storage OEM. Design ZEP-H2R for 350-bar inlet max conservatively. Specify NXS-Z3 pipe class for 700-bar as conservative basis. |
| R-03 | 20kV MVDC Topology at Facility Scale | MEDIUM | Engage Eaton and ABB (US mfg) early. Evaluate 1,500V DC backbone fallback. Design NXS-Z1 for both 20kV and 1,500V options. |
| R-04 | D-48V-01 Open — 48V Controls Bus | MEDIUM | Resolve at OER Gate 2. Specify PEM module skids with provision for local 800V → 48V DC/DC conversion as backup. |
| R-05 | NXS-Z3 Recycle Header Sizing for H₂ Purge Volume | LOW | Size NXS-Z3 recycle to include ZEP purge (50–120 CFM aggregate) in design flow. Include purge flow totalizer on APS-ZEP-001. Check valve on recycle return. |
17. Spares Register
| Crit. | Equipment / Item | Tag | First Fill | Operating Stock |
|---|
| A | PEM Fuel Cell Stack (full replacement, per module) | ZEP-PEM-001 to -128 | 4 spare stacks | Per OEM degradation schedule |
| A | BESS Battery Module (replacement set) | ZEP-BSS-001 | 1 module set | Per cell degradation |
| A | HVIL Connector Assembly (ASI-PBK-QC) | ZEP-PEM (all) | 10 spare connectors | 5/yr |
| A | H₂ Regulation Station — pneumatic fail-closed valve | ZEP-H2R-001 to -004 | 2 valve assemblies | 1/yr |
| B | PEM Membrane Electrode Assembly (MEA) inspection kit | ZEP-PEM-001 to -128 | 1 kit per OEM schedule | Per OEM |
| B | Zone Bus MULTILAM contact set (per segment) | ZEP-ZBS-001 to -004 | 1 set per segment | Per degradation |
| B | SuperCap Bank (full replacement) | ZEP-SCB-001 to -128 | 4 spare banks | Per cycle life |
| B | DC/AC Inverter — control board assembly | ZEP-INV-001 to -016 | 2 spare boards | 1/yr |
| C | H₂ gas detection sensor (point detector) | ZEP-H2R (all) | 8 sensors | 4/yr |
| C | Zero-E Thermal Recovery Loop pump mechanical seal | ZEP-TRL-001 | 2 seal sets | 1 set/yr |
| C | Coolant (water-glycol) charge | ZEP-TRL-001 | Full system charge | Annual top-up |
18. Warranty Register
| Equipment | Warranty Period | OEM Guarantee | Coverage |
|---|
| ZEP-PEM-001 to -128 — PEM Fuel Cell Modules | 24 mo from FAT | Yes — ASI (OEM pass-through) | Output power at rated conditions. Stack degradation limited to OEM-specified rate. Membrane contamination excluded if H₂ supply deviates from §4.1 spec. |
| ZEP-BSS-001 — BESS | 24 mo from FAT | Yes — OEM direct | Capacity ≥90% of nameplate at end of warranty. Black Start per §5.3. LFP — no thermal runaway. |
| ZEP-SCB-001 to -128 — SuperCap Banks | 18 mo from FAT | Yes — OEM via ASI | Capacitance retention ≥90%. Cycle life ≥500,000 cycles. |
| ZEP-ZBS-001 to -004 — Zone Bus Segments | 24 mo from FAT | Yes — ASI | Current rating and thermal at 5,300A. Liquid cooling leak-free. |
| ZEP-MVB-001 — MVDC Backbone | 24 mo from FAT | Yes — OEM direct | Interrupting capacity, voltage rating, switching function. |
| ZEP-H2R-001 to -004 — H₂ Regulation Stations | 18 mo from FAT | Yes — OEM via ASI | Pressure regulation ±2% of setpoint. Fail-closed <50 ms. |
| ZEP-INV-001 to -016 — DC/AC Inverters | 24 mo from FAT | Yes — OEM direct | Output power at rated load; efficiency ≥96% at 75–100% load. |
| ZEP-TRL-001 — Zero-E Thermal Recovery Loop | 18 mo from FAT | Yes — ASI | Piping leak-free. Coolant at 85–95°C confirmed at FAT. |
18.1 Warranty Administration
The ASI is the single point of warranty contact for all sub-tier OEM suppliers within Zero-E PowerBlock scope. The Unitized Warranty Passport issued at FAT covers all ZEP-tagged modules as an integrated system. Carbotura Engineering maintains the warranty log per ISO 9001:2015 Clause 8.7. PEM module performance warranty is conditional on H₂ supply meeting §4.1 specification at the NXS-Z3/ZEP-H2R interface.
18.2 Open Decisions Governing This Document
| D-# | Description | Priority | Blocks |
|---|
| D-H2-01 | H₂ distribution header pressure in NXS-Z3 — 20–50 bar parametric | 🔴 OER Gate 2 | ZEP-H2R spec; NXS-Z3 pipe class; PEM inlet regulator design |
| D-48V-01 | 48V DC controls bus — retained in Nested DC topology? | 🟡 OER Gate 2 | ZEP module skid design; ICD tables |
| D-ASI-01 | ASI Vendor Selection | 🔴 OER Gate 0 | All procurement; FAT; Unitized Warranty Passport |
| D-ZEP-APS-01 | H₂ purge gas routing (Session 8) | CLOSED | Routes to NXS-Z3 recycle. No flare path. |
END OF DOCUMENT — CBT-ZEP-TDS-001 | Rev 0 | April 2026 | CONFIDENTIAL — CARBOTURA INC. — ALL RIGHTS RESERVED
RevCon 3 Performance Baseline | ASI Integration Model | Class 2 OER ±15% Target | ECN Pending: 20kV → 30kV MVDC
