Preliminary Market Consultation – Compact SOV / Walk-to-Work offshore logistics and accommodation concept for the operation and maintenance (O&M) of the ONAS offshore substation platforms in the German Baltic Sea

50Hertz Transmission GmbH, acting as a utility contracting entity, is conducting a non-binding Preliminary Market Consultation pursuant to Section 26 SektVO. The purpose of this consultation is to explore whether, and under which operational and commercial conditions, a compact SOV-based (Service Operation Vessel) or Walk-to-Work (W2W) offshore logistics and accommodation concept could support the continuous operation and maintenance (O&M) of the offshore grid connection platforms (ONAS) in the German Baltic Sea. The consultation is intended to inform potential future procurement decisions. 50Hertz is interested in practical market solutions, indicative commercial logic and the main assumptions underlying such information. No offers, binding prices, detailed cost breakdowns or internal calculation models are requested. As an indicative size reference, a concept with approximately 30–50 persons on board (POB), DP2 capability, suitable W2W access to OSS interfaces, platform supply capability and Baltic Sea operability is being considered. This indication is for orientation only and does not constitute a preferred design, a preferred supplier or a mandatory technical specification. The market consultation pursues, in particular, the following objectives: Identifying the current market offering of compact, fit-for-purpose SOV / W2W concepts for continuous Baltic Sea O&M operations, as well as larger market-available SOV / CSOV tonnage. Assessing the technical feasibility of DP2 capability, W2W access up to approximately Hs 2.5 m, platform supply, transfer of fluids (diesel, oil, fresh water, grey water, waste water) and crane interfaces with the OSS. Understanding realistic market routes (newbuild, conversion, existing tonnage, shared use, campaign, winter, seasonal or back-charter models) and their associated lead times and availability drivers. Exploring the main commercial cost drivers and meaningful contractual and remuneration models. Exploring available and emerging propulsion, energy and emissions-reduction concepts, including Baltic Sea-specific framework conditions. Assessing whether such a concept can be economically implemented for the planned scope (9 relevant ONAS platforms, max. 24–48 POB per platform, approximately 3,000–10,000 person-days of offshore work per year, distributed over four campaigns).