SeaRenergy Offshore Holding

What SeaRenergy Offshore Holding does

SeaRenergy Offshore Holding GmbH is a Hamburg-based, privately held provider of integrated professional services for the offshore wind industry, operating across the full value chain from transport and installation concepts through commissioning to operations and maintenance. Founded in 2010 by Jan Boje Steffens, the group delivers engineering and consultancy through subsidiaries Elbe1, Con4Mare, and Seartec; marine coordination, port logistics, vessel inspection, and crew transfers via Con4Mare; QHSE services; and project staffing plus crew change management. Following the November 2025 acquisition of hemmerschütz Solutions GmbH, the group now also offers in-house offshore maintenance and repair capabilities, including corrosion protection, welding, concrete repairs, and rotor, tower, and foundation services.

The company sells exclusively to enterprise customers, including transmission system operators (notably TenneT), OEMs (Siemens Energy under a multi-year framework covering 13+ converter platforms), and offshore wind developers (Baltic Power, Ailes Marines, Ørsted, Vattenfall). GTM is direct and consultative, secured via competitive tenders and multi-year framework contracts, with delivery supported by a chartered Platform Supply Vessel fleet (BOS Prelude under a 7-year firm charter, Spirit of Emden operated under parent ownership) and technology partnerships for vessel traffic management (Vissim AS) and subsea robotics (Tethys Robotics AG). Geographic footprint spans Germany, the Netherlands, the UK, Poland, France, and Cyprus, with regional offices in Hamburg, Den Haag, Emden, Limassol, and Gdynia. Pricing is project-specific and quote-based, with no public tiers, and revenue is generated through professional services and managed services streams tied to long-duration frameworks and vessel charters.

Name

SeaRenergy Offshore Holding

Legal name

SeaRenergy Offshore Holding GmbH

Website

https://searenergy.com

Company type

Private

Founded year

2010

Operating status

Operating

Headcount range

101–250 employees

Short description

SeaRenergy Offshore Holding is a Hamburg-based independent provider of integrated engineering, marine, QHSE, staffing, and maintenance services for the European offshore wind value chain, serving transmission system operators, OEMs, and wind farm developers via subsidiaries and chartered vessels.

Ownership category

akta.pro rank

Headquarters

HQ city

Hamburg

HQ country

Germany

HQ region

Europe

Offices5 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Technology or R&D, Infrastructure, Marketing or Sales

Revenue model

1. Engineering and Technical Consultancy Services: Professional services including owners engineering, technical project management, EPCI management, market intelligence, compliance, and engineering design provided through subsidiaries Elbe1, Con4Mare, and Seartec. Revenue is project-based with multi-year framework contracts.
2. Marine Services: Marine coordination, platform supply logistics, crew transfers, vessel inspection, and port logistics services. Includes chartered vessel operations (BOS Prelude, Spirit of Emden) providing regular supply runs to offshore platforms.
3. QHSE Services: Quality, Health, Safety, and Environment consultancy services including concepts, on-site support, risk and safety management, and certification services.
4. Offshore Experts and Contract Staffing: Project staffing for onshore and offshore positions, crew change and travel management, visa application management, and training management services.
5. Vessel Charter Services: Long-term vessel charter arrangements (e.g., 7-year firm charter for BOS Prelude with options to extend) providing offshore supply capabilities as part of integrated service packages.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels4 records

Core offering

SeaRenergy Offshore Holding provides integrated engineering, marine coordination, QHSE, and offshore staffing services for the offshore wind energy value chain. The company supports transmission system operators, wind farm developers, and OEMs from transport and installation through operations and maintenance, leveraging proprietary logistics software, vessel traffic management systems, and a chartered platform supply vessel fleet.

Product overview

SeaRenergy Offshore Holding is an independent provider of comprehensive services for the offshore wind industry, involved in the whole value chain from T&I concepts to installation and operation & maintenance. The company operates through four main service categories: Engineering Services (provided by subsidiaries Elbe1, Con4Mare, and Seartec), Marine Services, QHSE Services, and Offshore Experts Services. Key named offerings include the Cargo Run Service using chartered vessels like the Spirit of Emden and BOS Prelude, and the Tethys ONE Subsea Inspection service delivered through strategic partnership with Tethys Robotics. Founded in 2010, the company provides integrated onshore and offshore logistics, marine coordination, and specialized maintenance services for offshore wind farms and grid connection systems.

Differentiator

Problem solved

Functional benefit

Products and services

• Engineering Services
• Marine Services
• QHSE Services
• Offshore Experts (Staffing)
• Platform Supply Logistics
• Cargo Run Service (CRS)

Quantifiable outcome

• Supporting first build offshore wind farm in Poland
• +1 more outcomes

Named customers6 records

Segments3 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature3 records

Partnerships

Four partnerships are on record, tiered strategic and core.

• Tethys Robotics AGstrategicTechnology or Integration · 27 May 2025Strategic partnership integrating the Tethys ONE underwater robot system into SeaRenergy's offshore service portfolio. The Tethys ONE is a compact underwater robot with advanced navigation and acoustic/contact-based sensors for automated subsea inspections. Partnership to commence with pilot projects in North Sea and Baltic Sea focusing on offshore wind farm structures and subsea cables.
• Asian Spirit Steamship Company GmbH & Cie. KGcoreOthers · 1 April 2025Parent company ownership of PSV Spirit of Emden, which SeaRenergy operates under its Cargo Run Service for regular offshore supply runs to converter platforms in German Bight and UK waters.
• Britoil Offshore ServicescoreChannel Partner/ Reseller/ Distributor · 25 March 2025Long-term charter agreement for Platform Supply Vessel (PSV) BOS Prelude with firm duration of seven years and options to extend for up to three additional years. Vessel to be deployed under SeaRenergy's multi-year offshore infrastructure contract with Siemens Energy and available for other supply duties in German Bight and UK sector.
• Vissim ASstrategicTechnology or IntegrationPartnership for Vessel Traffic Management and Maritime Surveillance Systems providing innovative solutions for construction site monitoring. Currently supporting two projects in operation with a third project to be added. Partnership enables SeaRenergy to provide comprehensive marine coordination services including ship registration, personnel check-in, inspection, and construction site monitoring.

Scale indicators4 records

Recent moves7 records

Expansion highlights6 records

Market position

Competitive moat5 records

Customer concentration

• LinkedInde.linkedin.com/company/searenergy-offshore-holding-gmbh

Revenue estimate

Valuation estimate

Number of profiles

Profiles5 records

Subsidiaries6 records

Funding overview

Funding rounds

Investors

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

M&A

Investments

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

Frequently asked questions about SeaRenergy Offshore Holding