Knowledge Base

Vessel Operations — Operational Requirements

Draft Medium Research 4,538 words Created Mar 4, 2026

Vessel Operations — Operational Requirements for The Claw

A converted Aframax tanker operating as a mobile plasma processing vessel in the Great Pacific Garbage Patch (GPGP), ~1,000nm from Honolulu. This document covers the full operational picture: power, cycles, weather, crew, maintenance, safety, and annual costs.


1. Power Budget

Vessel Baseline

A standard Aframax tanker has:

  • Main engine: 11-14 MW (single slow-speed diesel)
  • Auxiliary generators: Typically 3x diesel generators, 1.5-2.5 MW each (4.5-7.5 MW total installed)
  • Emergency generator: 500-750 kW
For The Claw, the main propulsion engine is retained for transit. The conversion adds plasma processing equipment, syngas engines, and collection gear. The auxiliary power plant is significantly upgraded or replaced.

Power Demand by Mode

Transit Mode (Honolulu <-> GPGP)

SystemPower DrawNotes
Main engine (propulsion)11-14 MWFull ahead, 14-15 knots
Navigation & comms50 kWRadar, GMDSS, satcom
Hotel load400-600 kWCrew of 25, HVAC, lighting, galley
Steering gear100-150 kW
Total transit~12-15 MWAll diesel, no syngas generation
Fuel consumption in transit: ~45-55 tonnes/day of heavy fuel oil (HFO) or marine diesel oil (MDO) at 14-15 knots. At 1,000nm each way and ~15 knots, transit is ~67 hours (~3 days) each direction. Round trip burns ~270-330 tonnes of fuel.

Sources: Aframax specifications via Wikipedia, Wartsila tanker design data

Processing Mode (On Station, Full Operations)

SystemPower DrawNotes
Plasma reactor800-1,200 kWPyroGenesis PRRS at 5-10 TPD. Torch consumption ~0.8 MWh/ton at 10 TPD scale
Syngas cleanup & conditioning150-300 kWScrubbers, coolers, filters, compressors
Shredder / pre-processing200-400 kWSize reduction, dewatering, sorting
Collection equipment300-500 kWConveyor booms, winches, pumps, nets handling
Syngas engine/genset-1,500 to -3,000 kWGeneration — syngas converted to electricity
Hotel load400-600 kWFull crew operations
Water maker (RO desalination)50-80 kW10-15 m3/day capacity
HVAC150-250 kWTropical Pacific, full crew
Lighting & galley80-120 kW24-hour operations
Station-keeping (see below)500-1,500 kWIf DP; near-zero if drift mode
Gross demand~2,700-5,000 kWExcluding syngas generation
Syngas generation1,500-3,000 kWFrom processed plastic
Net from diesel~0-2,500 kWDepends on throughput and DP mode
Critical note: The energy loop math (detailed in energy-balance.md) suggests syngas from 5-10 TPD of plastic can generate 4-9 MWh/day net after powering the torch. At processing rates toward 10 TPD, syngas should cover most or all processing + hotel load. Below ~5 TPD, diesel backup is needed.

Sources: PyroGenesis PRRS specs via pyrogenesis.com, plasma energy balance via NETL, syngas energy output ~815-900 kWh/ton via Science Council for Global Initiatives

Station-Keeping

Two options:

ModePower DrawAccuracyCostRecommendation
Dynamic Positioning (DP1/DP2)500-1,500 kW continuousWithin 10mHigh fuel burn, high maintenance on thrustersOverkill for plastic collection
Drift mode with periodic repositioningNear-zero (occasional thruster use)Drifts with currentMinimal fuelRecommended
The GPGP is within the North Pacific Subtropical Gyre where currents are slow (0.1-0.3 knots). Plastic accumulates precisely because the water is relatively calm. Drift mode is the correct choice — the vessel drifts with the same currents that concentrate the plastic, repositioning with main engine or bow thruster only when needed to move to higher-density areas.

DP2 (redundant dynamic positioning) would be required if the vessel were holding station near a fixed structure (pipeline, wellhead). For plastic collection in open water with no collision risk, DP is unnecessary cost and fuel burn.

Sources: DP system overview via Kongsberg Maritime, Seavium DP guidance-for-your-offshore-operation)

Hotel Load Only (Standby / Weather Hold)

SystemPower DrawNotes
HVAC150-250 kWCannot shut down in tropics
Lighting30-50 kWReduced to essential
Galley30-50 kWCrew still needs to eat
Water maker50-80 kWContinuous freshwater production
Navigation & comms50 kWRadar, AIS, satcom always on
Bilge/ballast pumps20-40 kWIntermittent
Medical bay5-10 kWStandby
Total hotel only~350-530 kWSingle diesel generator
This is the weather-hold or maintenance mode. One auxiliary diesel generator covers it comfortably.

Source: Offshore vessel hotel load data via ScienceDirect, Marine Insight

Emergency / Backup Power

RequirementCapacityNotes
Emergency generator500-750 kWSOLAS requirement, auto-start within 45 seconds
UPS for critical systems50 kWNavigation, comms, fire detection
Emergency lighting10 kW18-hour battery backup per SOLAS
Diesel fuel reserve30-day minimumFor transit home if syngas system fails completely
Diesel backup sizing: Even if the syngas system fails completely, the vessel must be able to run hotel load on diesel (~500 kW) for up to 30 days, plus transit home (~3 days at full power). This means carrying approximately 400-500 tonnes of diesel fuel as operational reserve, plus enough for the return transit.

Total Installed Power Summary

SourceCapacityRole
Main diesel engine11-14 MWPropulsion (transit only)
Syngas engine/genset(s)2-3 MWPrimary on-station power
Auxiliary diesel generators3x 1.5-2 MW (4.5-6 MW)Backup, transit aux, supplement
Emergency diesel generator750 kWSOLAS emergency power
Total installed~18-24 MW

2. Operating Cycle — The 28-Day Rotation

Cycle Breakdown

PhaseDaysActivity
Transit out3Honolulu to GPGP at 14-15 knots
Processing operations18-20Collection + plasma processing
Scheduled maintenance2-3Electrode replacement, equipment checks, repairs
Weather downtime2-4Built into processing days (estimated)
Transit return3GPGP to Honolulu
Port / crew change1-2In Honolulu (overlaps with next cycle crew)
Total cycle~28 days

Realistic Processing Uptime

Of the ~20 days on station:

  • Weather downtime: 2-4 days (sea state too high for collection; see Section 3). Processing MAY continue if feedstock buffer is loaded, but collection stops.
  • Maintenance: 1-2 days for plasma torch electrode swaps and equipment inspections
  • Net collection days: ~14-18 days
  • Net processing days: ~16-20 days (processing can continue from buffer stock during collection downtime)
Feedstock buffer strategy: Maintain a 2-3 day buffer of shredded, dewatered plastic in storage hoppers. This allows the plasma reactor to continue operating during short weather holds when collection is paused. Buffer capacity needed: ~15-30 tonnes (2-3 days at 5-10 TPD).

Crew Changeover

The changeover happens in Honolulu. The incoming crew flies commercial to Honolulu and boards while the outgoing crew departs. This is a hot swap — the vessel does not shut down systems. Key officers overlap for 4-8 hours for handover briefings.

Industry standard for remote offshore: 28/28 (equal time on/off) is standard for drilling and remote FPSO operations. Some operations use 28/14 (28 on, 14 off) to reduce crew costs, but 28/28 is better for retention and fatigue management at this distance.

Source: Offshore rotation standards via WTS Energy, Worldwide Recruitment Solutions

Supply Vessel Schedule

A dedicated supply run is needed once per cycle (every 28 days), plus the vessel carries supplies during its own transit.

What must be delivered (cannot generate on board):

  • Fresh food and provisions (frozen/dry stores for 28 days loaded in port; fresh provisions via supply vessel at ~day 14)
  • Diesel fuel (if burn rate exceeds carried reserves)
  • Plasma torch electrodes and consumables
  • Medical supplies and pharmaceuticals
  • Spare parts (pre-positioned based on maintenance schedule)
  • Potable water chemicals (RO membrane treatment)
  • PPE, cleaning supplies, operational consumables
What IS generated on board:
  • Freshwater (RO desalination — 10-15 m3/day for crew of 25)
  • Electricity (syngas + diesel)
  • Vitrified slag (byproduct, inert — stored or dumped per permit)
  • Metal ingots (from inorganic fraction — stored for port offload)

Maintenance Windows

During each 28-day cycle:

  • Daily: Equipment inspections, greasing, filter checks (1-2 hours)
  • Weekly: Comprehensive equipment inspection, fluid sampling (4-8 hours)
  • Per cycle: Plasma torch electrode inspection/replacement (8-16 hours downtime)
  • Per cycle: Collection equipment inspection, net/boom repair (4-8 hours)
During port calls:
  • Stores loading (8-12 hours)
  • Slag/metal offload (4-8 hours)
  • Shore-side specialist maintenance if needed
  • Crew medical checks

Bad Weather Protocol

Sea StateHs (Sig. Wave Height)CollectionProcessingTransit
0-3 (calm to slight)0-1.25mFull opsFull opsFull speed
4 (moderate)1.25-2.5mFull opsFull opsFull speed
5 (rough)2.5-4.0mReduced/stoppedContinue from bufferFull speed
6 (very rough)4.0-6.0mStoppedContinue if safeReduced speed
7+ (high+)6.0m+StoppedShutdown & secureWeather routing
Key principle: Collection is the weather-sensitive bottleneck. The plasma reactor, being internal, can operate in higher sea states than the collection equipment. The feedstock buffer bridges the gap.


3. Weather & Sea State — GPGP Conditions

Location

The GPGP is centered roughly at 25-35N, 135-155W, within the North Pacific Subtropical Gyre. This is the convergence zone of the North Pacific Current, the California Current, the North Equatorial Current, and the Kuroshio Extension.

Annual Wave Climate (Estimated from WAVEWATCH III Hindcast Data)

MonthAvg Hs (m)Max Hs (m)Avg Wind (knots)Notes
Jan2.5-3.56-1015-25Winter storms — worst month
Feb2.5-3.56-915-25Winter storm tracks active
Mar2.0-3.05-812-22Improving
Apr1.5-2.54-610-18Transition to calm season
May1.5-2.03-58-15Good operating window opens
Jun1.0-2.03-58-15Prime season
Jul1.0-1.52-48-12Prime season — calmest
Aug1.0-1.52-48-12Prime season — calmest
Sep1.0-2.03-58-15Good, but hurricane risk
Oct1.5-2.54-710-18Transition to winter
Nov2.0-3.05-812-22Winter storm tracks return
Dec2.5-3.56-1015-25Winter storms — bad
Note: These are estimates derived from North Pacific wave climate literature and NOAA WAVEWATCH III model outputs. The GPGP sits in the subtropical high, which is calmer than the storm track to the north (40N+) but still gets long-period swell from distant storms. Actual conditions vary year to year, especially with El Nino / La Nina cycles.

Sources: NOAA high seas forecast products, Copernicus satellite altimetry data, Colosi et al. 2021 — seasonal wave height cycles

Operational Season

There IS a season. The Ocean Cleanup pauses GPGP operations for winter (roughly November-March) because harsh winter conditions reduce collection efficiency and increase equipment damage risk.

SeasonMonthsViability
PrimeJun-Sep80-90% collection uptime. Calm seas, light winds. Best plastic concentration (less wind-driven submersion).
ShoulderApr-May, Oct60-75% collection uptime. Occasional weather holds.
WinterNov-Mar40-60% collection uptime. Frequent storm interruptions. Processing can continue from buffer but collection is unreliable.
Recommendation: Operate year-round but plan for reduced throughput in winter. Alternatively, use winter months for dry dock / major maintenance. The Ocean Cleanup returns to port for winter — a mobile processing vessel could do the same, scheduling the 5-year survey and major refits for November-February.

Sources: The Ocean Cleanup — System 002 seasonal operations, Ocean Cleanup — GPGP overview

Storm Frequency

The GPGP area (25-35N) is south of the main North Pacific storm track (which runs 40-50N). Direct hits from extratropical storms are rare in summer, more common in winter when the storm track dips south. Tropical cyclone (hurricane) risk exists June-November but the central Pacific rarely sees direct landfalls at this latitude.

Expected weather downtime: ~15-25% of on-station time annually (higher in winter, lower in summer).

Currents

Surface currents in the GPGP are typically 0.1-0.3 knots. This is the gyre's center — water moves slowly, which is why plastic accumulates. This is favorable for drift-mode station-keeping.


4. Crew & Logistics

Crew Composition

Total crew: 24-28 per rotation (two full crews needed for 28/28 rotation)

RoleCountNotes
Master (Captain)1Unlimited Master license, STCW certified
Chief Officer1Navigation, cargo/collection ops, safety officer
2nd Officer1Navigation watch, collection operations
3rd Officer1Navigation watch, environmental monitoring
Chief Engineer1Overall engineering, plasma system oversight
2nd Engineer1Syngas engine, power plant
3rd Engineer1Auxiliary systems, water maker, HVAC
Electrician / ETO1Electrical systems, PLC, automation
Plasma Operations Lead1PyroGenesis-trained, reactor operations
Plasma Operator224-hour reactor watch coverage (with lead = 3 total)
Collection Operations Lead1Boom/net deployment, deck operations
Deck crew (ABs)4Collection equipment, deck maintenance, mooring
Bosun1Deck maintenance, rigging, seamanship
Motorman / Oiler2Engine room watch, mechanical maintenance
Medic / Paramedic1Advanced first aid, telemedicine, pharmacy
Cook / Steward2Galley, provisions, housekeeping
Environmental Officer1Emissions monitoring, waste tracking, regulatory compliance
Total~24-26
Key considerations:
  • Plasma operators are specialized — they need PyroGenesis training. Cannot be filled from general maritime crew pool.
  • 24-hour operations require 3-watch rotation for bridge, engine room, and plasma operations.
  • No helicopter crew — helicopter is not based on board (see below).
Sources: Maritime salary guide 2026, Crewlinker offshore vessel jobs

Rotation Model

Recommended: 28/28 (28 days on, 28 days off)

This is industry standard for remote offshore operations (drilling rigs, FPSOs far from shore). The key reasons:

  • Fatigue management: MLC 2006 and STCW mandate minimum rest hours. 28/28 prevents cumulative fatigue.
  • Crew retention: At 1,000nm from port, morale matters. Equal time on/off is the industry norm for remote work.
  • Total crew required: 2 full crews x 25 = 50 personnel on payroll (one crew on board, one crew on leave).
  • Travel: Crew flies commercial to/from Honolulu. The vessel transits to port for changeover.
Some FPSO operations in West Africa use 28/14 for cost savings (28 on, 14 off), but this requires a larger crew pool and leads to higher turnover.

Source: WTS Energy — 28/28 rotation

Helicopter Logistics

1,000nm is beyond the range of ANY offshore helicopter.

HelicopterMax RangeNotes
Sikorsky S-92539nmMost common offshore transport
AW139306nmMedium twin
AW169440nmMedium twin
At 1,000nm from Honolulu, helicopter crew transfer is not possible. Even the longest-range offshore helicopter (S-92) can only reach ~500nm, and that is one-way with no reserve fuel — operationally impossible.

Options for emergency medical evacuation: 1. USCG C-130 fixed-wing + rescue helicopter relay — USCG can deploy a C-130 from Barbers Point, HI to provide on-scene coordination and drop supplies. Rescue helicopter can be deployed from a USCG cutter if one is within range. 2. Vessel transit to meet helicopter — Steam toward Honolulu at 15 knots while helicopter flies out. Rendezvous at ~500nm from shore (~33 hours sailing + helicopter flight). 3. Medevac to passing vessel — Transfer patient to a faster vessel heading to port. 4. US Navy assets — Pearl Harbor is the closest major naval base. Navy can deploy long-range assets for life-threatening emergencies.

Cost: No helicopter operating budget needed for routine crew transfer (crew transfers happen in port). Emergency medevac would be a USCG operation (no direct cost, but insurance must cover it).

Sources: Fair Lifts — offshore helicopter guide

Supply Vessel Logistics

Frequency: Once per 28-day cycle (mid-cycle resupply of fresh provisions, mail, critical spares)

Supply vessel type: Platform Supply Vessel (PSV), ~60-80m, hired on spot or short-term charter from Honolulu.

Round trip for supply vessel: 1,000nm each way at 12 knots = ~83 hours each way = ~7 days round trip. This is expensive — the supply vessel is committed for a full week per delivery.

ItemCost EstimateNotes
PSV charter$30,000-45,000/dayPacific rates; spot market data
7-day round trip$210,000-315,000Per supply run
Fuel for PSV~$50,000-80,0007 days steaming, 15-20 tonnes/day
Per-cycle supply cost~$260,000-400,000Charter + fuel
Annual (13 cycles)~$3.4M-5.2MEstimate
Alternative: Reduce supply runs by carrying more stores during the vessel's own port call at each crew change. If the vessel loads 28 days of everything in port, mid-cycle supply runs may be needed only for urgent/unplanned items (every other cycle instead of every cycle).

Medical Capability

At 1,000nm from the nearest hospital (Queen's Medical Center, Honolulu), the vessel is 24-48+ hours from shore medical care even at full speed.

Required medical capability (per STCW, MLC 2006, and flag state requirements):

CapabilityDetails
Medical officerParamedic or advanced EMT minimum; offshore medic certification required
Ship's hospitalDedicated medical bay with examination table, monitoring equipment
PharmacyCategory A medicine chest (highest category for vessels >3 days from port)
Telemedicine24/7 satellite link to shore-based physician (companies like MSOS, MedAire)
Surgical capabilityLimited — stabilization and suturing. No major surgery.
DefibrillatorAED + manual defibrillator
OxygenTherapeutic oxygen supply, minimum 48 hours
Stretcher / basketFor helicopter hoist extraction if USCG reaches vessel
Dental emergency kitBasic extraction and pain management
The reality: At this distance, the medical strategy is stabilize and evacuate. Serious trauma, heart attack, stroke, or appendicitis requires getting the patient to shore ASAP. The vessel can steam toward Honolulu while coordinating USCG medevac.

Sources: STCW medical care requirements, MLC 2006 Regulation 4.1, MSOS offshore medical support

Communication Systems

SystemPurposeRedundancy
VSAT (Ku/Ka-band)Primary data, voice, telemedicine, weatherPrimary
Inmarsat Fleet BroadbandBackup data, voiceSecondary
Iridium satellite phoneEmergency voice, low-bandwidth dataTertiary
GMDSS (MF/HF/VHF)Distress, SAR coordination, weatherSOLAS required
EPIRBEmergency position beaconSOLAS required
SARTSearch and rescue transponderSOLAS required
AISVessel trackingSOLAS required
Monthly satcom cost: $5,000-15,000 depending on bandwidth tier. Telemedicine requires reliable video capability.


5. Maintenance & Reliability

Plasma Torch Electrode Replacement

ComponentLife ExpectancyReplacement TimeCost per UnitNotes
Graphite electrodes200-1,000 hours4-8 hours$2,000-10,000Varies by torch design and operating power. Consumption is fastest at start and end of electrode life.
Refractory lining6-12 months24-48 hours (major maintenance)$20,000-50,000Requires reactor cooldown
Syngas filters / scrubbers500-2,000 hours2-4 hours$1,000-5,000
Torch nozzle~500 hours2-4 hours$1,000-3,000
At 10 TPD, 24-hour operation: The reactor runs ~480 hours per cycle (20 days on station). Electrode replacement is needed at least once per cycle, possibly twice. Carry minimum 4 sets of electrodes per cycle.

Sources: PyroGenesis PRRS, Plasma torch electrode life data, PyroGenesis technical papers

Planned Maintenance Schedule

IntervalSystemsDuration
DailyEquipment rounds, oil checks, filter inspections1-2 hours
WeeklyFluid sampling, belt/chain inspection, greasing4-8 hours
Per cycle (28 days)Electrode swap, collection gear inspection, safety equipment checks8-16 hours
QuarterlyMain engine governor, alternator checks, safety valve testing, lifeboat service24-48 hours (in port)
AnnualUnderwater hull inspection (divers or ROV), classification society survey items, safety equipment recertification5-7 days (in port)
2.5 yearsIntermediate survey / docking survey7-14 days dry dock
5 yearsSpecial survey (full dry dock)3-6 weeks dry dock

Critical Spares Inventory

Must carry on board at all times:

CategoryItemsEstimated Value
Plasma system4x electrode sets, 2x nozzles, 2x igniter assemblies, refractory patch kit$80,000-120,000
Syngas engineInjector set, turbocharger cartridge, fuel pump, gaskets$40,000-60,000
Diesel generatorsInjector set, fuel pump, governor actuator, filters (6-month supply)$30,000-50,000
Collection equipmentSpare conveyor belts, hydraulic hoses, winch motor, boom cylinder seals$20,000-40,000
ElectricalSpare PLC module, VFD, contactors, fuses, cable$15,000-25,000
Hull/marinePump impellers, valve internals, shaft seals, RO membranes$20,000-30,000
SafetySCBA bottles, fire hose, extinguisher charges$5,000-10,000
Total spares inventory$210,000-335,000

Dry Dock

EventFrequencyDurationEstimated Cost
Intermediate surveyEvery 2.5 years7-14 days$800K-1.2M
Special surveyEvery 5 years3-6 weeks$1.2M-1.6M
LocationHonolulu (limited capacity) or US West Coast (LA, San Francisco, Portland, Seattle)
Tanker vessels cannot apply for extended dry docking under current classification rules — The Claw must follow the standard schedule.

Sources: Marine Insight — dry dock cost estimation, ResearchGate — tanker dry docking cost modeling

At-Sea Repair Capability

The engineering team (Chief Engineer + 2nd + 3rd + ETO + 2 motormen) must be capable of:

  • Plasma electrode replacement without shore support
  • Diesel generator overhaul (top-end)
  • Hydraulic system repair (collection equipment)
  • Electrical fault-finding and motor replacement
  • Welding and fabrication (dedicated workshop on board)
  • Basic hull patching (above waterline)
What cannot be repaired at sea:
  • Main engine crankshaft / bottom-end failure (tow to port)
  • Propeller / shaft damage (tow to port)
  • Major structural damage (emergency response)
  • Reactor refractory rebuild (port-side maintenance)

6. Safety & Emergency

Emergency Response at 1,000nm

AgencyCapabilityResponse Time
USCG District 14 (Honolulu)C-130 Hercules (airborne SAR coordination, supply drop)4-6 hours
USCG cutterIf one is in area — medical, firefighting, towVariable (hours to days)
US Navy (Pearl Harbor)Long-range assets for major emergency12-48 hours
Commercial vesselsAMVER system — nearby merchant ships can divertVariable
Self-rescueLifeboats, life rafts, EPIRB, SARTImmediate
Reality check: At 1,000nm from shore, the vessel is largely on its own for the first 4-6 hours minimum. Self-sufficiency in firefighting, flooding, and medical emergencies is essential.

Firefighting for Plasma Operations

Plasma gasification involves:

  • Temperatures exceeding 3,000C in the plasma arc
  • Syngas (hydrogen + carbon monoxide — flammable and toxic)
  • Molten slag at 1,400-1,600C
SystemCoverage
Fixed CO2 floodingReactor compartment, syngas piping area
Water mist / delugeReactor room, engine room
Foam systemFuel storage areas, deck
Portable extinguishersThroughout vessel
Fire detectionFlame detectors, smoke detectors, gas detectors (H2, CO) in all processing spaces
Gas-free ventilationForced ventilation with gas monitoring in all confined spaces
Emergency shutdown (ESD)One-button reactor shutdown, syngas system isolation
Syngas-specific hazards: CO is odorless and lethal. H2 is explosive in air at 4-75% concentration. Fixed gas detection with automatic ventilation and alarm is mandatory in all spaces where syngas is present.

Evacuation Procedures

ScenarioResponse
Abandon ship2x enclosed lifeboats (capacity: 100% crew each side), life rafts, immersion suits
Man overboardMOB procedures, fast rescue craft, dan buoy, EPIRB-equipped life ring
Medical evacuationSteam toward shore + USCG C-130 coordination for helicopter rendezvous at ~500nm
Fire / explosionMuster, boundary cooling, fight fire. If uncontrollable, prepare to abandon.

Environmental Spill Response

RiskMitigation
Diesel fuel spillSOPEP (Shipboard Oil Pollution Emergency Plan), absorbent booms, dispersant
Slag / residue overboardSlag is vitrified (inert glass-like solid) — minimal environmental risk, but still regulated
Syngas releaseLighter than air, disperses rapidly. Toxic if inhaled. Gas detection + forced ventilation
Collected plastic lossRe-release of collected plastic overboard during storm — net/containment system design must prevent this
Hydraulic oilBiodegradable hydraulic fluid for deck equipment where possible
MARPOL compliance: The vessel must meet MARPOL Annex I-VI requirements. Plasma processing emissions need to meet applicable air quality standards (MARPOL Annex VI, possibly EPA requirements given US flag/port).

Coast Guard / SAR Coordination

  • File voyage plans with USCG before each transit
  • Maintain AMVER (Automated Mutual-Assistance Vessel Rescue System) reporting
  • Daily position reports via Inmarsat
  • USCG District 14 duty officer contact maintained at all times
  • Nearest USCG cutter position tracked (USCG publishes positions for SAR planning)

7. Annual Operating Cost Model (OPEX)

Assumptions

  • 10-12 operating cycles per year (2-3 cycles lost to dry dock, major maintenance, or winter weather stand-down)
  • 28/28 crew rotation, 2 full crews
  • Honolulu as home port
  • Vessel is owned (not chartered) — no charter/lease cost in OPEX
  • All figures in USD, 2025 estimates

Crew Costs

RoleAnnual Salary (per person)Headcount (x2 crews)Annual Cost
Master$160,000-200,0002$320,000-400,000
Chief Officer$120,000-150,0002$240,000-300,000
2nd Officer$90,000-110,0002$180,000-220,000
3rd Officer$80,000-100,0002$160,000-200,000
Chief Engineer$150,000-180,0002$300,000-360,000
2nd Engineer$110,000-140,0002$220,000-280,000
3rd Engineer$85,000-105,0002$170,000-210,000
ETO / Electrician$90,000-110,0002$180,000-220,000
Plasma Ops Lead$120,000-150,0002$240,000-300,000
Plasma Operators (x2)$80,000-100,0004$320,000-400,000
Collection Ops Lead$90,000-110,0002$180,000-220,000
Bosun$70,000-85,0002$140,000-170,000
ABs (x4)$55,000-70,0008$440,000-560,000
Motormen (x2)$60,000-75,0004$240,000-300,000
Medic$90,000-120,0002$180,000-240,000
Cook/Steward (x2)$50,000-65,0004$200,000-260,000
Environmental Officer$85,000-110,0002$170,000-220,000
Subtotal salaries50$3,980,000-4,860,000
Benefits & insurance (30%)$1,194,000-1,458,000
Rotation travel (flights to/from Honolulu)$150,000-250,000
Total crew$5,324,000-6,568,000
Sources: Maritime Salary Guide 2026, Securewest salary guide

Fuel

ItemQuantityCost
Transit fuel (HFO/MDO)~300 tonnes x 10 round trips = 3,000 tonnes/year$1,800,000-2,400,000
Backup diesel (on-station generator use)~500-1,000 tonnes/year (depends on syngas reliability)$300,000-600,000
Lubricating oil~50 tonnes/year$100,000-150,000
Total fuel$2,200,000-3,150,000
Note: If syngas system achieves target reliability, on-station diesel backup drops significantly. First-year costs will be higher as the system is commissioned.

Consumables

ItemAnnual CostNotes
Plasma torch electrodes$100,000-200,000~20 sets/year at $5,000-10,000 each
Refractory lining repairs$50,000-100,000Partial relining 1-2x/year
Syngas filters & catalysts$30,000-60,000
RO membranes & chemicals$15,000-30,000
Collection equipment wear parts$50,000-100,000Nets, booms, conveyor belts
Provisions (food & stores)$200,000-300,00050 crew-months on board per year
PPE & safety consumables$20,000-40,000
Total consumables$465,000-830,000

Maintenance & Repair

ItemAnnual CostNotes
Planned maintenance (routine)$300,000-500,000Parts, contractor support in port
Unplanned repairs$200,000-400,000Contingency — things break
Dry dock (annualized)$400,000-600,000$1.2M-1.6M every 2.5-5 years
Classification society fees$50,000-80,000Annual survey, flag state fees
Total maintenance$950,000-1,580,000

Supply Vessel

ItemAnnual CostNotes
Mid-cycle supply runs$2,600,000-5,200,00010 runs/year at $260K-520K each
Alternative (reduced runs)$1,300,000-2,600,0005 runs/year if heavy loading in port
This is one of the largest variable costs. Minimizing supply runs by maximizing stores at each port call is critical.

Insurance

CoverageAnnual PremiumNotes
Hull & Machinery (H&M)$400,000-800,000Based on ~$50-100M vessel value, 0.5-1.5% premium
P&I (Protection & Indemnity)$200,000-400,000Crew liability, pollution, third-party
Environmental liability$100,000-300,000Plasma operations add risk premium
Cargo/processing liability$50,000-100,000Unusual cargo = unusual coverage
War risk / piracy$50,000-100,000Low risk in GPGP area
Total insurance$800,000-1,700,000
Note: This is a novel vessel class performing a novel operation. Underwriters will price uncertainty. First-year premiums may be higher until loss history is established. Estimates based on general FPSO and tanker insurance data.

Sources: Lloyd's List — vessel insurance

Helicopter Operations

$0 for routine operations — crew transfer happens in port. No ship-based helicopter.

Emergency medevac is covered by USCG (no direct cost) and insurance.

Port Fees & Shore Support

ItemAnnual CostNotes
Honolulu port fees (berthing, pilotage, tugs)$300,000-500,000~10-12 port calls/year
Waste disposal (slag offload)$50,000-100,000Vitrified slag disposal or sale
Shore-based management office$400,000-600,000Operations manager, logistics coordinator, admin, office lease
Regulatory & compliance$50,000-100,000EPA, USCG, flag state, classification
Satellite communications$100,000-180,000VSAT + Inmarsat + Iridium
Telemedicine service$30,000-50,00024/7 physician access
Weather routing service$20,000-40,000Professional meteorological support
Total port & shore$950,000-1,570,000

TOTAL ANNUAL OPEX SUMMARY

CategoryLow EstimateHigh Estimate
Crew costs$5,324,000$6,568,000
Fuel$2,200,000$3,150,000
Consumables$465,000$830,000
Maintenance & repair$950,000$1,580,000
Supply vessel$1,300,000$5,200,000
Insurance$800,000$1,700,000
Port fees & shore support$950,000$1,570,000
TOTAL ANNUAL OPEX$11,989,000$20,598,000

Rounded Estimate: $12M - $21M per year

Central estimate: ~$15-16M/year assuming moderate supply vessel frequency, reasonable syngas reliability, and no major unplanned events.

Cost per Tonne of Plastic Processed

ScenarioAnnual ThroughputAnnual OPEXCost per Tonne
Conservative (5 TPD, 200 processing days)1,000 tonnes$15M$15,000/tonne
Target (7.5 TPD, 220 processing days)1,650 tonnes$15M$9,100/tonne
Optimistic (10 TPD, 240 processing days)2,400 tonnes$16M$6,700/tonne
For context: The Ocean Cleanup's cost per tonne is not publicly disclosed but is estimated at $5,000-20,000/tonne for collection alone (no processing). The Claw's cost includes full plasma destruction.


Key Uncertainties & Risks

ItemImpactConfidence
Syngas energy recovery rateDetermines diesel backup needs — swings fuel budget by $500K+/yearMEDIUM — lab-proven, not field-proven on ocean plastic mix
Plasma system reliability at seaNovel installation — first years may have more downtimeLOW — no precedent for shipboard plasma at this scale
Supply vessel costsLargest variable OPEX item — charter rates volatileMEDIUM — can be managed with better port logistics
Insurance premiumsNovel operation = uncertain underwritingLOW — no loss history to anchor premiums
Crew retention for plasma opsSpecialized roles in remote location — recruitment challengeMEDIUM — premium pay and 28/28 rotation help
Winter weather downtimeCould reduce annual throughput 20-30% vs. optimistic estimatesHIGH — well-documented seasonal patterns
Electrode consumption rateCould be higher than lab data suggests due to salt contamination in feedstockMEDIUM — saltwater residue on ocean plastic may accelerate electrode wear

Data Sources & Confidence Key

  • KNOWN: Published specifications, regulatory requirements, established industry data
  • ESTIMATED: Derived from analogous operations (FPSO, offshore drilling, tanker operations) with reasonable adjustments
  • SPECULATIVE: Novel aspects of this operation with no direct precedent — flagged explicitly
Most cost figures are ESTIMATED based on analogous offshore operations. The plasma-specific costs are the least certain, as shipboard plasma gasification at this scale has no operational precedent.


Last updated: 2026-03-04 Research compiled from public sources including PyroGenesis technical papers, NOAA oceanographic data, maritime industry publications, and offshore operations benchmarks.