Offshore Heavy Transport

Heavy Marine Transportation Servicesoht.no

Seaway7 is an offshore wind installation contractor offering transport, installation, and cable lay services for wind turbine foundations, substations, and heavy transport. It serves offshore wind developers and utilities across Europe, the US, and Asia-Pacific via project-based EPCI contracts.

Company typePrivate
Founded2009
HeadquartersOslo, Norway
Headcount101–250
GTM typeB2B
OfferingServices

What Offshore Heavy Transport does

Seaway7 is an offshore wind installation contractor focused on the transport, installation, and commissioning of offshore wind farm components. The company's core service offerings include the installation of wind turbine generator (WTG) foundations, the transport and installation of offshore substations, inter-array and export cable lay, and heavy transport services for offshore energy infrastructure. Seaway7 also operates in the emerging floating offshore wind segment. The company serves offshore wind developers and utilities on a project-EPCI basis, with named project experience including Beatrice, Hornsea, Seagreen, Moray East, Hollandse Kust Zuid, and Hai Long, and a cumulative track record of over 800 WTG foundations installed, more than 30 substations delivered, over 2,500 km of cables laid, and 50+ projects completed.

Seaway7 operates a specialized fleet of vessels that constitutes the operational backbone of the business. The fleet includes six heavy transport vessels (Eagle, Falcon, Hawk, Osprey, Swan, Albatross), the heavy-lift vessel Seaway Strashnov, the cable lay vessel Seaway Ventus, and the foundation installation vessel Seaway Alfa Lift. The company operates across multiple geographies including the United Kingdom, Netherlands, Germany, Poland, the United States, and Taiwan, indicating both European offshore wind market concentration and selective international expansion. Seaway7 is a subsidiary of Subsea7 Group, publicly traded on the Oslo and Paris stock exchanges, with Stuart Fitzgerald as the current CEO and Lloyd Duthie appointed as incoming CEO effective 2026-04-01.

Seaway7's revenue model is project-based, multi-year EPCI contracting with offshore wind developers, where contracts are typically awarded through competitive tendering based on technical capability, fleet availability, and execution track record. Pricing is driven by vessel day rates, project scope, and installation complexity. The high capital intensity of the fleet and the project's long execution cycle create significant barriers to entry and strong switching costs, supporting a durable competitive position. Years of operational experience and accumulated know-how in offshore installation constitute a key intangible asset that influences developer selection of installation partners.

Offshore Heavy Transport firmographics

Firmographics

Name: Offshore Heavy Transport
Legal name: Seaway7
Website: https://oht.no
Company type: Private
Founded year: 2009
Operating status: Operating
Headcount range: 101–250 employees
Short description: Seaway7 is an offshore wind installation contractor offering transport, installation, and cable lay services for wind turbine foundations, substations, and heavy transport. It serves offshore wind developers and utilities across Europe, the US, and Asia-Pacific via project-based EPCI contracts.
Ownership category
akta.pro rank

Offshore Heavy Transport industry classification

Industry

Product category: Heavy Marine Transportation Services
NAICS: Water Transportation (483), Deep Sea Freight Transportation (483111), Deep Sea, Coastal, and Great Lakes Water Transportation (48311)
SIC: Water Transportation (4400), Arrangement Of Transportation Of Freight & Cargo (4731)
akta.pro primary industry: Heavy Lift / Breakbulk & RoRo Project Shipping (TLADAGAC)
akta.pro secondary industries: Oil & Gas / Energy Project Transport (Rigs, Pipe, Modules) (TLADAGAE), Marine & Offshore Assets (Rig Moves, FPSO/OSV Components) (TLACAIAE), Chartering & Heavy-Lift Vessel / Barge / RoRo Solutions (TLACAIAJ)

Keywords

Heavy transport vessels
Offshore wind logistics
Marine transportation services
Offshore module transport
Heavy lift vessels

Where Offshore Heavy Transport is headquartered

Location

Headquarters

HQ city: Oslo
HQ country: Norway
HQ region: Europe

Markets served

Offshore Heavy Transport business model

Business model

GTM type: B2B
Offering type: Services
Cost components: Operations, Personnel, Infrastructure, Supply Chain

Revenue model

Heavy Transport Services: Provides heavy transport vessel charter and operational services for offshore wind foundations, offshore modules, and oversized cargoes. Revenue is generated through project-based contracts for transportation services.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels2 records

Offshore Heavy Transport product offering

Product offering

Core offering

Offshore Heavy Transport operates as a transport and installation contractor and vessel operator in the specialized heavy transport vessel (HTV) market. The company provides heavy transport vessel charter and operational services for offshore wind foundations, offshore modules, and oversized floating and non-floating cargoes, using semi-submersible heavy transportation vessels, heavy deck carriers, and heavy lift vessels. Revenue is generated through project-based contracts for transportation services in the offshore energy sector.

Differentiator

Problem solved

Functional benefit

Products and services

Heavy Transport Vessel Charter Services Charter and operational services for heavy transport vessels, including semi-submersible heavy transportation vessels, heavy deck carriers, and heavy lift vessels. Designed for offshore wind developers, oil & gas operators, and clients requiring engineered transportation of oversized cargoes.
Offshore Wind Foundation Transportation Specialized transportation of offshore wind foundations using semi-submersible heavy transportation vessels. Serves offshore wind developers requiring transportation of foundations and related structures.
Offshore Module Transportation Heavy transport of offshore modules for oil and gas operators and offshore energy projects. Uses heavy lift vessels and semi-submersible carriers to deliver modules safely and on time.
Oversized Cargo Transportation Services Engineered transportation solutions for oversized floating and non-floating cargoes, supported by multi-modal logistics capabilities. Serves clients requiring complex, customized transportation projects in the offshore sector.

Companies that use Offshore Heavy Transport

Customer profile

Segments2 records

Ideal customer profiles2 records

Offshore Heavy Transport technology and API

Technology

Technology focussed No

API detail

Has API: No
API docs
API detail

Core technology

AI maturity

App detail

Feature1 record

Offshore Heavy Transport partnerships and signals

Strategic signal

Scale indicators1 record

Recent moves5 records

Expansion highlights4 records

Offshore Heavy Transport competitors and assessment

Company assessment

Direct peers

Royal Boskalis Westminster: Royal Boskalis is a leading Dutch maritime services company with a major heavy transport and offshore energy division. It directly competes with OHT in semi-submersible heavy transport vessel services for offshore wind foundations and oil & gas modules, operating one of the largest HTV fleets globally.
Van Oord: Van Oord is a Dutch marine contractor that operates heavy transport, heavy lift, and offshore installation vessels for offshore wind and oil & gas projects. It is identified as one of the key established Western operators competing with OHT in the heavy transport vessel market.
BigLift Shipping: BigLift Shipping is a Dutch heavy lift shipping company specializing in the worldwide transport of heavy and outsized cargo. It is a direct competitor in the project cargo and heavy transport vessel market, particularly for offshore and energy sector cargoes.
J. Ray McDermott: J. Ray McDermott is a US-based offshore construction and installation contractor with significant heavy lift and transport capabilities for offshore modules and structures. It is identified as a key Western competitor in the heavy transport vessel market.
Jumbo Maritime: Jumbo Maritime is a Dutch heavy lift shipping company specializing in complex offshore transport and installation projects. It competes directly with OHT in heavy lift and project cargo transport for offshore energy clients.

Broad incumbents

Subsea7: Subsea7 is the parent of Seaway7, a sister company in the offshore wind installation space that also operates heavy transport vessels. It is a major offshore energy services provider with strong overlap in offshore wind T&I services and heavy transport capabilities.
Saipem: Saipem is an Italian global engineering and construction company with a broad offshore EPCI (engineering, procurement, construction, installation) portfolio. It competes with OHT in offshore wind installation and oil & gas heavy transport, but operates as a much larger, diversified incumbent.
DEME Group: DEME is a Belgian dredging, marine engineering, and offshore renewable energy contractor with significant heavy lift and offshore installation capabilities. It competes with OHT in offshore wind T&I services as a broader marine contractor incumbent.

Emerging players

ZPMC (Shanghai Zhenhua Heavy Industries): ZPMC is a Chinese state-owned heavy equipment manufacturer and operator that has expanded into offshore wind installation and heavy transport vessels. It is an emerging competitor offering cost-competitive alternatives to Western operators.
COSCO Shipping Heavy Transport: COSCO Shipping operates heavy lift vessels and is expanding its presence in semi-submersible heavy transport for offshore wind. It represents an emerging Asian competitor that could pressure Western operators like OHT on pricing.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

Offshore Heavy Transport financial estimates

Financial estimate

Revenue estimate

Valuation estimate

Offshore Heavy Transport leadership team

Management profile

Number of profiles

Offshore Heavy Transport funding detail

Funding detail

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

Offshore Heavy Transport M&A and investment

M&A and investment

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Offshore Heavy Transport

What does Offshore Heavy Transport do?

Is Offshore Heavy Transport a public or private company?

Offshore Heavy Transport is a private company. It is classified as public and is currently operating.

When was Offshore Heavy Transport founded?

Offshore Heavy Transport was founded in 2009. It employs 101 to 250 people.

Where is Offshore Heavy Transport based?

Offshore Heavy Transport is headquartered in Oslo, Norway, in the Europe region.

How does Offshore Heavy Transport make money?

One revenue line is on record: heavy Transport Services.

Who are Offshore Heavy Transport's main competitors?

Direct peers on record are Royal Boskalis Westminster, Van Oord, BigLift Shipping, J. Ray McDermott and Jumbo Maritime. Broad incumbents are Subsea7, Saipem and DEME Group. Emerging players are ZPMC (Shanghai Zhenhua Heavy Industries) and COSCO Shipping Heavy Transport.

Does Offshore Heavy Transport have an API?

No public API is recorded for Offshore Heavy Transport.

What industry is Offshore Heavy Transport in?

Offshore Heavy Transport's product category is Heavy Marine Transportation Services. Its primary akta.pro industry code is TLADAGAC, Heavy Lift / Breakbulk & RoRo Project Shipping, with a secondary code of TLADAGAE, Oil & Gas / Energy Project Transport (Rigs, Pipe, Modules). Its NAICS code is 483 and its SIC code is 4400.