Offshore floating photovoltaic (OFPV) plants require cable allowance at interfaces between floating blocks to support maintenance access and accommodate relative motion. Because synchronized relative-motion records are often unavailable during early design, this allowance cannot be calibrated directly. This study proposes a fixed-topology multi-objective method for joint inverter siting and low-voltage collector-cable routing. CAD polylines are decomposed into fixed segments, and route-specific inter-block crossings, and a bounded gap-allowance factor is applied only at the crossings. NSGA-II generates nondominated layouts that minimize cable investment and the present value of resistive-loss cost while satisfying equipment-capacity, string-count, current, and voltage-drop constraints. The method is applied to a 5.1212 MWp grid-connected OFPV plant under the nominal routing case (γs = 1). Compared with the manual design, the selected compromise layout reduces collector-cable investment by 7.0% and the present value of power-loss cost by 14.9%, producing a 9.76% reduction in the modeled total collection-system cost. The results demonstrate the economic value of coordinated inverter siting and cable routing while identifying the data required for future dynamic-allowance calibration.
Offshore wind power forecasting is challenging because rapidly varying metocean conditions induce strong non-stationarity and heterogeneous power-generation dynamics. This study proposes RegimeMoE-PatchTST, a metocean-conditioned mixture-of-experts framework for multi-step offshore wind power forecasting. For each historical window, four statistical descriptors of seven metocean variables are extracted to form a 28-dimensional condition vector. Three independently parameterized PatchTST networks serve as forecasting experts, while a gating network maps the condition vector to sample-dependent weights and softly fuses their multi-step predictions. The entire framework is trained end-to-end without predefined regime labels. Experiments on two offshore wind turbine datasets at 2-, 4-, 8-, and 16-h horizons show that the proposed model achieves the lowest mean squared error (MSE) in all eight turbine–horizon settings and reduces average MSE by 3.69% relative to PatchTST. Ablation results verify the importance of both metocean-conditioned routing and dynamic expert fusion, while regime-wise evaluation shows MSE reductions of 7.7% and 8.1% under high-wind and high-turbulence conditions. These results demonstrate improved adaptability and forecasting accuracy under heterogeneous offshore operating conditions.
Traditional onshore hydrogen production systems are constrained by limited land availability and freshwater resources, which restrict their potential for large-scale deployment. Offshore renewable energy-based hydrogen production systems provide an effective approach for accommodating abundant marine renewable energy resources and establishing integrated green hydrogen supply chains, representing a promising pathway toward future zero-carbon energy systems. However, system-level integration technologies remain in the stages of theoretical development and engineering demonstration, with several critical technical challenges that limit their commercial deployment and large-scale application. This paper presents a narrative review of the typical configurations and key technologies of offshore renewable energy-based hydrogen production systems. Based on recent global research advances and representative marine engineering demonstrations, major technical challenges, including stochastic fluctuations of renewable power generation, seawater corrosion, and multi-physics-field monitoring, are comprehensively analyzed. Corresponding mitigation strategies, such as multi-energy complementary integration and corrosion-resistant material optimization, are summarized. Furthermore, from a system-level perspective, the coupling mechanisms among multiple subsystems are investigated, and a whole-chain coordinated optimization framework is proposed. This review provides theoretical foundations and engineering references for the large-scale deployment and integrated development of offshore green hydrogen production systems.
