As wind turbine rotors grow in size and Greece advances its offshore wind energy initiatives, this study analyzes the structural behavior of offshore wind turbine blades using fluid–structure interaction (FSI) methods. The blade skin and shear webs of the International Energy Agency (IEA) 15 MW wind turbine, assumed to operate in the Aegean Sea, are examined. Computational fluid dynamics (CFD) simulations are conducted for two steady-state wind speeds based on local weather data, followed by finite element analysis (FEA) to assess advanced materials in terms of strength, cost, and carbon footprint. This is the first study to evaluate bamboo- and basalt-based composite materials under Greek offshore wind conditions using FSI methods. Bamboo composites are affordable and sustainable, but their limited durability reduces their viability in offshore environments. The simulation results indicate that using bamboo composites as blade skin may lead to damage due to the excessive loads on offshore wind turbine blades. In contrast, basalt fiber composites are also environmentally viable and offer superior strength, corrosion resistance, and long-term performance, making them a promising alternative. However, their naturally high density may impact the overall weight of the structure. This study concludes that offshore wind technology in the Aegean is feasible but remains costly and environmentally demanding. The further development and adoption of basalt fibers may serve as a gateway to more environmentally friendly offshore structures.

The use of liquid hydrogen (LH₂) as a zero-emission energy carrier is increasingly relevant for next-generation transport systems, requiring reliable cryogenic storage solutions operating at approximately −253 °C. This study presents a computational analysis of LH₂ storage tanks, focusing on the coupled thermal–structural behavior of insulated cryogenic vessels under varying design parameters. The present work expands upon our previous effort by employing the Finite Element Method (FEM) to perform a parametric investigation of these tanks. This is accomplished by examining the effect of the insulating material and the change in the storage volume of LH₂, as well as the change in the selected hydrogen boil-off rate (BOR). Results show that increasing the BOR from 0.1%/h to 1.0%/h reduces the required insulation thickness and mass by approximately 90% across all configurations, significantly altering system-level mass distribution. Substituting polyurethane foam (PUR-64) with lower-density equivalent (PUR-32) yields heat-flow reductions of up to 19.5% in two configurations, while producing an unexpected increase of approximately 10% in one case due to nonlinear thermal-gradient effects. Furthermore, increasing the hydrogen storage volume from 50 m³ to 150 m³ enhances gravimetric efficiency by 58%, 75%, and up to 104% depending on tank geometry. The results demonstrate the demand for robust numerical models, due to the nonlinear dependence of the materials involved with temperature.