For a containerized, three-leg SWATH-flavored seastead: 44′ equilateral triangle living structure, NACA 0035 foil legs, battery-electric rim-drive propulsion, solar topsides, tension-leg helical-anchor mooring, and twin-vessel underway coupling.
| Parameter | Value |
|---|---|
| Overall footprint | Equilateral triangle, 44.0 ft (13.4 m) per side; 7 ft (2.13 m) wall height |
| Legs / buoyancy bodies | 3 × NACA 0035, 21.5 ft (6.55 m) long, ~8.5 ft (2.59 m) chord, truncated trailing edge; 50% submerged |
| Displacement at target waterline | ~27,500 lb (~12.5 t) |
| Battery mass fraction | ~25% of displacement (≈3.1 t → roughly 400–450 kWh usable LiFePO₄) |
| Propulsion | 6 × 1.5 ft (0.46 m) fixed rim-driven thrusters, differential steering; per-leg independent power |
| Energy | Solar roof across triangle (~70–78 m²; est. 12–14 kWp); triple-redundant inverters/charge controllers |
| Station-keeping | 3 pairs of helical mooring screws, tension-leg pull-down (~3 ft), Caribbean deployment |
| Shipping | All parts in one 45′ High Cube container (62,000 lb max payload) |
| Extras | Bolt-on heave plates, grating walkway, stern dinghy (14′ RIB + HARMO), inter-vessel walkway mode |
Note: “LiPo4” is treated here as LiFePO₄ (LFP), which is what you want for marine safety and cycle life anyway — classification societies scrutinize lithium installations heavily.
| Firm / Institution | Location | Best Role on Your Project | Est. Duration | Est. Cost (USD) | Fit |
|---|---|---|---|---|---|
| Shanghai Bestway Marine Engineering Design | Shanghai | Lead designer & integrator (basic + detail design) | 6–10 months | $140k–$280k | ★★★★★ |
| MARIC (Marine Design & Research Inst. of China, 708th Inst., CSSC) | Shanghai | Alternative lead designer; deepest special-hull-form bench | 9–15 months | $300k–$650k | ★★★★☆ |
| GMEC (Guangzhou Marine Engineering Corp., CSSC) | Guangzhou | Regional lead designer near the southern yacht/workboat cluster | 7–12 months | $170k–$360k | ★★★★☆ |
| CIMC Raffles (offshore engineering) | Yantai | Mooring / global-performance / heave-plate specialist (or heavyweight lead) | 8–14 mo (lead) 3–6 mo (specialist) | $250k–$600k (lead) $80k–$200k (specialist) |
★★★★☆ |
| CSSRC (China Ship Scientific Research Center, 702nd Inst.) | Wuxi | Towing-tank / seakeeping model-test partner | 2–4 months per campaign | $60k–$160k per campaign | ★★★★★ |
| 712th Research Institute (Wuhan Inst. of Marine Electric Propulsion) | Wuhan | Battery / DC-grid / rim-drive system specification & integration | 3–6 months | $50k–$150k | ★★★★☆ |
| University groups (SJTU, HEU, WUT, JUST) | Shanghai / Harbin / Wuhan / Zhenjiang | Low-cost CFD, seakeeping simulation, structural FEA, tank time | 3–8 months | $40k–$130k per study | ★★★★☆ |
| SSSRI (Shanghai Ship & Shipping Research Institute) | Shanghai | Alternate lead designer; research-heavy culture | 7–12 months | $150k–$330k | ★★★☆☆ |
| China Classification Society (CCS) | Nationwide | Rule guidance + plan approval + survey (partner, not designer) | Ongoing | $30k–$90k | Essential |
Considered but deprioritized: SDARI (merchant-ship focus), COOEC (oil-&-gas scale), Hudong-Zhonghua / Jiangnan / DSIC design institutes (large military & commercial tonnage), and Zhuhai yacht-builder engineering departments (Heysea, Sunbird, Jet Tern — useful later for DFM/build partnering, not as lead NA).
An independent, privately held design house with a long track record in tugs, ferries, workboats, patrol craft, and yachts, including regular work for foreign clients. Accustomed to delivering to CCS, BV, DNV, and ABS rule sets and to producing CNC-friendly aluminum and steel production packages.
Estimated scope/time/cost: Concept freeze through detail/production drawings, weight & stability book, scantlings, container-packing drawings, class liaison: 6–10 months, $140k–$280k.
China’s largest comprehensive ship and offshore design institute. Broad portfolio spanning unconventional hull forms, small-waterplane concepts, passenger vessels, dredgers, and offshore structures, with strong in-house hydrodynamics and close class relationships.
Estimated scope/time/cost: Full concept→detail package incl. seakeeping reports and class plans: 9–15 months, $300k–$650k.
The CSSC-affiliated design house in Guangzhou, working a mixed portfolio of ferries, small commercial craft, and offshore support vessels. Geographically adjacent to the Pearl River Delta yacht and aluminum-boat manufacturing cluster (Zhuhai, Foshan, Guangzhou).
Estimated scope/time/cost: 7–12 months, $170k–$360k for a comparable scope to Bestway.
One of China’s premier offshore engineering organizations: semi-submersibles, jack-ups, wind-turbine installation vessels, aquaculture ships. Deep competence in global performance analysis, station-keeping, and wave-response mitigation — i.e., your heave plates and tension-leg scheme.
Estimated scope/time/cost: Mooring + global analysis + heave-plate package: 3–6 months, $80k–$200k. Full lead-designer role: 8–14 months, $250k–$600k.
China’s flagship hydrodynamics laboratory: among Asia’s largest towing tanks, seakeeping/maneuvering basins, and cavitation facilities. This is where novel Chinese hulls get validated.
Estimated scope/time/cost: $60k–$160k per campaign (model build + tests + report); a two-campaign program (resistance/propulsion, then seakeeping with heave plates on/off) typically lands at $120k–$300k total, 2–4 months per campaign.
China’s dedicated marine electric-propulsion institute: podded and rim-driven thrusters, marine battery systems, DC distribution grids, fuel cells, and high-redundancy architectures.
Estimated scope/time/cost: Power-system design package: 3–6 months, $50k–$150k; alternatively engage them as a hardware supplier and fold the fee into equipment pricing.
Shanghai Jiao Tong University (State Key Lab of Ocean Engineering), Harbin Engineering University, Wuhan University of Technology, and Jiangsu University of Science and Technology all take contracted studies: CFD hull-form optimization, seakeeping simulation, structural FEA, and tank time in their own or partner facilities.
Estimated scope/time/cost: $40k–$130k per study package, 3–8 months depending on queue and scope.
A research-and-design institute with strong seakeeping and ship-systems heritage. A reasonable alternate lead if Bestway/GMEC are unavailable, though its center of gravity is merchant and fleet-support work. Estimate: 7–12 months, $150k–$330k.
Not a designer, but engage them early. A first-of-kind battery-electric, tension-leg, container-shipped habitable platform will raise novel-rule questions: damaged stability, lithium-battery fire safety, habitability, bolted-aluminum fatigue, and mooring factor applicability. Early pre-agreement on the applicable rule set (CCS sea-going rules, small-craft provisions, ISO 12215 where appropriate) prevents expensive redesign. If you target international insurance or resale, parallel conversations with BV/DNV/ABS China offices are worthwhile — CCS will simply be the fastest and cheapest domestically. Estimate: $30k–$90k for approval + surveys through build (excluding travel).
For this project the highest-value configuration is a lean lead + specialists model rather than a single mega-institute:
| Phase | Content | Duration | Est. Cost (USD) |
|---|---|---|---|
| P0 — Specification & RFQ | Freeze requirements, issue RFQ to 3–4 firms, evaluate bids | 4–6 weeks | $5k–$15k (internal/legal) |
| P1 — Concept freeze | Weight loop, GA, initial stability, foil/leg placement study | 2–3 months | $40k–$80k |
| P2 — Analysis & testing (parallel) | CFD parametrics; CSSRC resistance/propulsion then seakeeping; mooring analysis | 3–4 months | $150k–$350k |
| P3 — Basic design + class submission | Scantlings, damage stability, battery-system basis, CCS plan approval round 1 | 2–3 months | $60k–$120k |
| P4 — Detail / production design | Kit-ready drawings, CNC data, weld/bolt specs, packing plan, assembly manual | 3–4 months | $80k–$160k |
| P5 — Build support | Shipyard queries, survey attendance, trials support | Ongoing | $20k–$50k |
Total elapsed: roughly 10–15 months. Overlaps compress this; class approval rounds and model-basin queues extend it.
| Scenario | Configuration | Total Est. Cost | Elapsed |
|---|---|---|---|
| Lean | University-led analysis + Bestway production design + CCS; desk studies instead of tank tests | $220k–$420k | 9–13 months |
| Balanced (recommended) | Bestway/GMEC lead + CSSRC two-campaign test program + CIMC Raffles mooring package + 712 power spec + CCS + peer review | $300k–$550k | 10–15 months |
| Premium | MARIC or CIMC Raffles as full lead, expanded test program, dual-class consultation | $450k–$850k | 12–18 months |
Hold a 20–30% contingency on whatever figure you budget — first-of-kind concepts almost always generate one extra analysis or redesign loop.