Advancements and Challenges in Marine Renewable Energy and Marine Structures

Journal Name	Impact Factor	CiteScore	Launched Year	First Decision (median)	APC
Energies energies	3.2	7.3	2008	16.8 Days	CHF 2600	Submit
Inventions inventions	1.9	4.9	2016	21.9 Days	CHF 1800	Submit
Journal of Marine Science and Engineering jmse	2.8	5.0	2013	16.5 Days	CHF 2600	Submit
Processes processes	2.8	5.5	2013	14.9 Days	CHF 2400	Submit
Sustainability sustainability	3.3	7.7	2009	17.9 Days	CHF 2400	Submit

31 pages, 1255 KB

Open AccessArticle

Numerical Investigation on the Effect of Flexible Connector Configurations on the Hydrodynamic Behavior of Floating Photovoltaics

by Yuhan Li, Xiang Li, Deshen Chen, Xing Chen, Yan Zhang, Ming Sheng and Hongliang Qian

J. Mar. Sci. Eng. 2026, 14(10), 876; https://doi.org/10.3390/jmse14100876 - 8 May 2026

Viewed by 186

Abstract

During the global transition toward cleaner energy infrastructure, floating photovoltaic (FPV) systems have emerged as a research focus in renewable energy technologies due to their distinctive spatial utilization advantages. This study examines the hydrodynamic performance of a novel FPV system comprising multiple floating [...] Read more.

During the global transition toward cleaner energy infrastructure, floating photovoltaic (FPV) systems have emerged as a research focus in renewable energy technologies due to their distinctive spatial utilization advantages. This study examines the hydrodynamic performance of a novel FPV system comprising multiple floating modules connected via flexible connectors to a circular frame. Three distinct connection schemes among the floating modules were designed for comparative analysis. To ensure computational accuracy, a numerical model was established and validated against existing experimental data from a 2 × 3 scaled array. Although the validation setup differs from the novel configurations proposed in this study, the results confirm the reliability of the adopted numerical method. Based on this validated model, time-domain analyses were conducted to evaluate the six-degree-of-freedom (6-DOF) motions of the FPV, as well as the dynamic responses of the flexible connectors and mooring system under various wave periods, heights, and directions. The study shows that the motion differences in FPV under different connection schemes are mainly observed in short wave periods and oblique waves. At a wave direction of 45°, the maximum differences in surge and sway motions among the schemes reach 0.2 m. The disparity in mooring tension and connector tension for different connection schemes increases as the wave period decreases and the wave height increases. Specifically, the maximum difference in connector tension attains 10 kN under a wave period of 9 s and a wave direction of 45°, while the peak difference in mooring chain tension reaches 13 kN at a wave direction of 90°. The dynamic responses of the connectors and mooring chains in the second connection scheme are superior to those of the other two schemes. The numerical simulations identify the optimal connection scheme. The results provide theoretical guidance for the design and practical application of FPV system. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

19 pages, 14779 KB

Open AccessArticle

Numerical Investigation on the Thermal Management Performance of the PCM and Fin Network Structure for Lithium-Ion Batteries

by Yiyao Chu, Shian Li, Ruiyang Zhang and Qiuwan Shen

J. Mar. Sci. Eng. 2026, 14(9), 776; https://doi.org/10.3390/jmse14090776 - 23 Apr 2026

Viewed by 413

Abstract

With the accelerated transformation of green shipping and the advancement of ship electrification, lithium-ion batteries have become the core solution for ship propulsion due to their advantages of high energy density and zero emission. Efficient thermal management serves as a key technical support [...] Read more.

With the accelerated transformation of green shipping and the advancement of ship electrification, lithium-ion batteries have become the core solution for ship propulsion due to their advantages of high energy density and zero emission. Efficient thermal management serves as a key technical support to ensure the safe and stable operation of batteries, extend their service life, and mitigate the risk of thermal runaway. Lithium-ion batteries accumulate heat during discharge, and pure phase change material (PCM) cooling systems are limited by low thermal conductivity, leading to excessive battery temperature rise and poor temperature uniformity. To address this problem, RT42 (a paraffin-based PCM with a melting temperature range of 311.15–316.15 K) was selected as the PCM in this study. The battery thermal management system (BTMS) coupling RT42 with a three-dimensional fin network structure was designed. Numerical simulations were conducted via ANSYS Fluent, and the enthalpy-porosity method was adopted to simulate the PCM phase change process. The effects of fin distribution, spacing and layer number on BTMS performance were systematically investigated and compared. Results show that the heat transfer process in the PCM can be significantly improved due to the three-dimensional fin network, and the battery maximum temperature can be reduced by 7.53 K compared with the pure PCM system. This study provides theoretical support for the design and optimization of high-efficiency BTMS. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

18 pages, 1100 KB

Open AccessReview

Environmental Policy and Risk Regulatory Framework for Sustainable Tidal Current Energy in China

by Ran Guo, Zhuzhou Liu, Hanbing Wei, Gang Wang, Shuyike Zhao and Yuncheng Deng

Sustainability 2026, 18(7), 3224; https://doi.org/10.3390/su18073224 - 25 Mar 2026

Viewed by 597

Abstract

The advancement of sustainable energy is a key component of the achievement of the Sustainable Development Goals. Technology advancements have made tidal current energy (TCE) a promising renewable energy source. China possesses abundant TCE resources and has gradually incorporated TCE into its energy [...] Read more.

The advancement of sustainable energy is a key component of the achievement of the Sustainable Development Goals. Technology advancements have made tidal current energy (TCE) a promising renewable energy source. China possesses abundant TCE resources and has gradually incorporated TCE into its energy and marine development policies. In China, TCE projects are currently being implemented on a large scale. However, despite policy-level recognition, TCE development in China has received limited regulatory attention, particularly with respect to environmental protection and ecological risk governance. Existing governance frameworks largely rely on general marine environmental and ecological policies, which are insufficient to address the three-dimensional, underwater characteristics and cumulative ecological risks. This study analyzes the evolution of China’s TCE-related laws and policies and identifies key deficiencies in current environmental regulation. To promote the sustainable TCE projects, the paper proposes tentative recommendations to promote the sustainable development of TCE in China, including the formulation of specialized environmental impact assessment guidelines grounded in the precautionary principle, future policies for addressing the cumulative environmental impact of large-scale TCE deployment, and the establishment of an environmental risk assessment system tailored to the data limitations and ecological characteristics of TCE exploitation. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

38 pages, 18338 KB

Open AccessArticle

Damage Characterisation of Scour in Riprap-Protected Jackets and Hybrid Foundations

by João Chambel, Tiago Fazeres-Ferradosa, Mahdi Alemi, Francisco Taveira-Pinto and Pedro Lomonaco

J. Mar. Sci. Eng. 2026, 14(2), 114; https://doi.org/10.3390/jmse14020114 - 6 Jan 2026

Cited by 1 | Viewed by 670

Abstract

The global transition towards sustainable energy has accelerated the development and deployment of offshore wind turbines. Jacket foundations, commonly installed in intermediate to deep water depths to access available space and higher load capacities, are built to withstand intensified hydrodynamic loads. Due to [...] Read more.

The global transition towards sustainable energy has accelerated the development and deployment of offshore wind turbines. Jacket foundations, commonly installed in intermediate to deep water depths to access available space and higher load capacities, are built to withstand intensified hydrodynamic loads. Due to their structural complexity near the seabed, however, they are prone to local and global scour, which can compromise stability and increase maintenance costs. While extensive research has addressed scour protections around monopiles, limited attention has been given to complex foundation geometries or even hybrid configurations that combine energy-harvesting devices with structural support. These hybrid systems introduce highly unsteady flow fields and amplified turbulence effects that current design frameworks appear to be unable to capture. This study provides an experimental characterisation of scour damage in riprap-protected jackets as well as additional tests for a hybrid jacket foundation. A novel adaptation of a high-resolution overlapping sub-area methodology was employed. For the first time, it was successfully applied to quantify the damage to riprap protections for a complex offshore foundation. Results revealed that, although hybrid jackets showed the capacity to attenuate incident waves, the scour protection experienced damage numbers (S_3D) two to six times higher than conventional jackets due to flow amplifications. The findings highlight the need for revised design guidelines that can account for the complex hydrodynamic-structural interactions of next-generation marine harvesting technologies integrated into complex foundations. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

19 pages, 7267 KB

Open AccessArticle

Experimental and Numerical Investigation of the Structural Behavior of Steel Cylindrical Shells Under Lateral Load Considering Fixed and Frictional Boundary Conditions

by Won Seok Choi, Jung Min Sohn and Sang Jin Kim

J. Mar. Sci. Eng. 2025, 13(11), 2179; https://doi.org/10.3390/jmse13112179 - 17 Nov 2025

Viewed by 646

Abstract

Wind turbine tower structures composed of slender steel cylindrical shells mainly serve as primary load-bearing components and can be particularly susceptible to buckling due to their thin walls. Ensuring the structural safety of wind turbines therefore requires a clear understanding of the behavior [...] Read more.

Wind turbine tower structures composed of slender steel cylindrical shells mainly serve as primary load-bearing components and can be particularly susceptible to buckling due to their thin walls. Ensuring the structural safety of wind turbines therefore requires a clear understanding of the behavior of slender cylindrical shells, which is influenced by material properties, boundary conditions, and loading scenarios. This study experimentally investigates the structural responses of scaled cylindrical structures representing wind turbine towers beyond the proportional limit including the ultimate and post-ultimate strength depending on boundary conditions (fully and frictionally supported). Lateral loads were applied at the top of the specimens to simulate concentrated loads transferred from wind forces on the blades. Furthermore, a numerical model was developed to analyze the structural behavior of the tower validated against the experimental test results. The results provide valuable insights into optimizing the structural design of both onshore and offshore wind turbine towers, contributing to enhanced safety and performance under varying load conditions. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

43 pages, 14490 KB

Open AccessArticle

Numerical Analysis of the Near-Wake Flow Field of Two Closely Spaced Wind Turbines with Passive Flow Control Ducts

by Maytham M. Abid and Marc Marín-Genescà

Inventions 2025, 10(6), 104; https://doi.org/10.3390/inventions10060104 - 13 Nov 2025

Cited by 1 | Viewed by 1271

Abstract

The growing demand for renewable energy in space-constrained environments highlights the need for compact, high-efficiency wind energy systems. Conventional bare wind turbine (BWT) arrays suffer from severe wake interactions and performance degradation when operated in tandem or closely spaced configurations. To address these [...] Read more.

The growing demand for renewable energy in space-constrained environments highlights the need for compact, high-efficiency wind energy systems. Conventional bare wind turbine (BWT) arrays suffer from severe wake interactions and performance degradation when operated in tandem or closely spaced configurations. To address these limitations, this study investigates the aerodynamic performance and near-wake dynamics of a novel multi-ducted wind turbine (MDWT) system that integrates passive flow-control technique (PFCT) into an innovative fixed-duct design. The objective is to evaluate how tandem ducted arrangements with this integrated mechanism influence wake recovery, vortex dynamics, and power generation compared with multi-bare wind turbine (MBWT) system. A numerical approach is employed using the Unsteady Reynolds-Averaged Navier–Stokes (URANS) formulation with the k–ω SST turbulence model, validated against experimental data. The analysis focuses on two identical, fixed-orientation ducts arranged in tandem without lateral offset, tested under three spacing configurations. The results reveal that the ducted system accelerates the near-wake flow and displaces velocity-deficit regions downward due to the passive flow-control sheets, producing stronger inflow fluctuations and enhanced turbulence mixing. These effects improve wake recovery and mitigate energy losses behind the first turbine. Quantitatively, the MDWT array achieves total power outputs 1.99, 1.90, and 1.81 times greater than those of the MBWT array for Configurations No. 1, No. 2, and No. 3, respectively. In particular, the second duct in Configuration No. 1 demonstrates a 3.46-fold increase in power coefficient compared with its bare counterpart. These substantial gains arise because the upstream duct–PFCT assembly generates a favorable pressure gradient that entrains ambient air into the wake, while coherent tip vortices and redirected shear flows enhance mixing and channel high-momentum fluid toward the downstream rotor plane. The consistent performance across spacings further confirms that duct-induced flow acceleration and organized vortex structures dominate over natural wake recovery effects, maintaining efficient energy transfer between turbines. The study concludes that closely spaced MDWT systems provide a compact and modular solution for maximizing energy extraction in constrained environments. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

29 pages, 7789 KB

Open AccessFeature PaperArticle

Wave Energy Conversion to Decarbonize Offshore Aquaculture: Multi-Level Techno-Economic Analysis for a Case Study in Peniche, Portugal

by Maïlys Bertrand, Gianmaria Giannini, Ajab Gul Majidi, Cassandre Senocq, Paulo Rosa-Santos and Daniel Clemente

Energies 2025, 18(22), 5934; https://doi.org/10.3390/en18225934 - 11 Nov 2025

Viewed by 1025

Abstract

By 2050, global population growth will lead to a significant increase in demand for animal-based products, including seafood. Aquaculture is a key solution to meet these needs while reducing pressure on wild aquatic stocks. However, its environmental footprint and energy demand remain open [...] Read more.

By 2050, global population growth will lead to a significant increase in demand for animal-based products, including seafood. Aquaculture is a key solution to meet these needs while reducing pressure on wild aquatic stocks. However, its environmental footprint and energy demand remain open concerns. This study explores the co-location of offshore aquaculture with a wave energy converter—WaveRoller—as a renewable power source. Using a 44-year dataset from the Portuguese coast near Peniche, the analysis evaluates the survivability and operation of the WaveRoller, long-term percentile trends, seasonal energy production, extrapolated extreme events using probabilistic modeling, and confidence intervals for energy costs. A scenario-based range of energy demand is constructed from a baseline blue mussel production of over 400 tons/yr. The K-Means clustering method is applied to reduce data size while maintaining its representativeness. Results show that a 600 kW WaveRoller is similarly suited to operational wave conditions compared to a 1000 kW device, though it excels when aquaculture energy demand peaks in Summertime. The probability that a single WaveRoller fails to meet annual aquaculture energy needs is nearly zero, though, during Summer, it can become statistically significant. The opposite is verified on survivability during Winter, under harsher wave conditions. The Levelized Cost of Energy is calculated for different expenditure scenarios, with minimum values slightly under 200 EUR/MWh being reported only under ideal conditions. Future work should include climate change scenarios and life cycle assessments to better evaluate environmental impacts and techno-economic viability. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

20 pages, 3950 KB

Open AccessArticle

Hydrodynamic Performance and Motion Response of a Novel Deep-Water TLP Floating Offshore Wind Turbine

by Ronghua Zhu, Zongyuan Lai, Chunlong Li, Haiping Qian, Huaqi Yuan, Yingchun Xie and Ke Sun

J. Mar. Sci. Eng. 2025, 13(11), 2131; https://doi.org/10.3390/jmse13112131 - 11 Nov 2025

Cited by 1 | Viewed by 1133

Abstract

The deployment of floating offshore wind turbines (FOWTs) in deep, typhoon-prone waters like the South China Sea requires platforms with exceptional stability. However, the performance validation of novel Tension Leg Platform (TLP) concepts under such extreme metocean conditions remains a significant research gap. [...] Read more.

The deployment of floating offshore wind turbines (FOWTs) in deep, typhoon-prone waters like the South China Sea requires platforms with exceptional stability. However, the performance validation of novel Tension Leg Platform (TLP) concepts under such extreme metocean conditions remains a significant research gap. This study addresses this by numerically evaluating a novel TLP design, including a regular hexagonal topology, a unique bracing structure and heave plates, and an increased ballast-tank height. A coupled numerical framework, integrating potential-flow theory and blade element momentum (BEM) theory within ANSYS-AQWA (2023), was established to simulate the TLP’s dynamic response to combined irregular wave, current, and turbulent wind loads. The resulting time-series data were analyzed using the Continuous Wavelet Transform (CWT) to investigate non-stationary dynamics and capture transient peak loads critical for fatigue sizing, which demonstrated the platform’s superior stability. Under a significant wave height of 11.4 m, the platform’s maximum heave was limited to 0.86 m and its maximum pitch did not exceed 0.3 degrees. Crucially, the maximum tension in the tendons remained below 22% of their minimum breaking load. The primary contribution of this work is the quantitative validation of a novel TLP design’s resilience in an understudied, harsh deep-water environment, confirming the feasibility of the concept and presenting a viable pathway for FOWT deployment in challenging offshore regions. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

25 pages, 6572 KB

Open AccessArticle

DLC-Organized Tower Base Forces and Moments for the IEA-15 MW on a Jack-up-Type Support (K-Wind): Integrated Analyses and Cross-Code Verification

by Jin-Young Sung, Chan-Il Park, Min-Yong Shin, Hyeok-Jun Koh and Ji-Su Lim

J. Mar. Sci. Eng. 2025, 13(11), 2077; https://doi.org/10.3390/jmse13112077 - 31 Oct 2025

Viewed by 1138

Abstract

Offshore wind turbines are rapidly scaling in size, which amplifies the need for credible integrated load analyses that consistently resolve the coupled dynamics among rotor–nacelle–tower systems and their support substructures. This study presents a comprehensive ultimate limit state (ULS) load assessment for a [...] Read more.

Offshore wind turbines are rapidly scaling in size, which amplifies the need for credible integrated load analyses that consistently resolve the coupled dynamics among rotor–nacelle–tower systems and their support substructures. This study presents a comprehensive ultimate limit state (ULS) load assessment for a fixed jack-up-type substructure (hereafter referred to as K-wind) coupled with the IEA 15 MW reference wind turbine. Unlike conventional monopile or jacket configurations, the K-wind concept adopts a self-installable triangular jack-up foundation with spudcan anchorage, enabling efficient transport, rapid deployment, and structural reusability. Yet such a configuration has never been systematically analyzed through full aero-hydro-servo-elastic coupling before. Hence, this work represents the first integrated load analysis ever reported for a jack-up-type offshore wind substructure, addressing both its unique load-transfer behavior and its viability for multi-MW-class turbines. To ensure numerical robustness and cross-code reproducibility, steady-state verifications were performed under constant-wind benchmarks, followed by time-domain simulations of standard prescribed Design Load Case (DLC), encompassing power-producing extreme turbulence, coherent gusts with directional change, and parked/idling directional sweeps. The analyses were independently executed using two industry-validated solvers (Deeplines Wind v5.8.5 and OrcaFlex v11.5e), allowing direct solver-to-solver comparison and establishing confidence in the obtained dynamic responses. Loads were extracted at the transition-piece reference point in a global coordinate frame, and six key components (Fx, Fy, Fz, Mx, My, and Mz) were processed into seed-averaged signed envelopes for systematic ULS evaluation. Beyond its methodological completeness, the present study introduces a validated framework for analyzing next-generation jack-up-type foundations for offshore wind turbines, establishing a new reference point for integrated load assessments that can accelerate the industrial adoption of modular and re-deployable support structures such as K-wind. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

23 pages, 2921 KB

Open AccessArticle

Investigating Ammonia as an Alternative Marine Fuel: A SWOT Analysis Using the Best–Worst Method

by Canberk Hazar and Alper Seyhan

Sustainability 2025, 17(20), 9314; https://doi.org/10.3390/su17209314 - 20 Oct 2025

Cited by 1 | Viewed by 2930

Abstract

The shipping industry remains heavily dependent on heavy fuel oils, which account for approximately 77% of fuel consumption and contribute significantly to greenhouse gas (GHG) emissions. In line with the IMO’s decarbonization targets, ammonia has emerged as a promising carbon-free alternative. This study [...] Read more.

The shipping industry remains heavily dependent on heavy fuel oils, which account for approximately 77% of fuel consumption and contribute significantly to greenhouse gas (GHG) emissions. In line with the IMO’s decarbonization targets, ammonia has emerged as a promising carbon-free alternative. This study evaluates the strategic viability of ammonia, especially green production, as a marine fuel through a hybrid SWOT–Best–Worst Method (BWM) analysis, combining literature insights with expert judgment. Data were collected from 17 maritime professionals with an average of 15.7 years of experience, ensuring robust sectoral representation and methodological consistency. The results highlight that opportunities hold the greatest weight (0.352), particularly the criteria “mandatory carbon-free by 2050” (O3:0.106) and “ammonia–hydrogen climate solution” (O2:0.080). Weaknesses rank second (0.270), with “higher toxicity than other marine fuels” (W5:0.077) as the most critical concern. Strengths (0.242) underscore ammonia’s advantage as a “carbon-free and sulfur-free fuel” (S1:0.078), while threats (0.137) remain less influential, though “costly green ammonia” (T3:0.035) and “uncertainty of green ammonia” (T1:0.034) present notable risks. Overall, the analysis suggests that regulatory imperatives and environmental benefits outweigh safety, technical, and economic challenges. Ammonia demonstrates strong potential to serve as viable marine fuel in achieving the maritime sector’s long-term decarbonization goals. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

20 pages, 3732 KB

Open AccessArticle

Numerical Verification of an Anchor-Free Jack-Up Installation Method for Offshore Wind Turbine Structures Using Tugboat Fleet

by Min Han, Young IL Park, A Ra Ko, Jin Young Sung and Jeong-Hwan Kim

J. Mar. Sci. Eng. 2025, 13(10), 1906; https://doi.org/10.3390/jmse13101906 - 3 Oct 2025

Viewed by 935

Abstract

With the rapid expansion of offshore wind power, efficient installation methods for 10 MW offshore wind turbines (OWTs) are increasingly being required. Conventional approaches using installation vessels, heavy-lift barges, and mooring systems incur high costs, long schedules, and weather-related constraints, particularly in harsh [...] Read more.

With the rapid expansion of offshore wind power, efficient installation methods for 10 MW offshore wind turbines (OWTs) are increasingly being required. Conventional approaches using installation vessels, heavy-lift barges, and mooring systems incur high costs, long schedules, and weather-related constraints, particularly in harsh seas such as the West Sea and Jeju. This study investigates an anchor-free installation method for jack-up-type OWTs employing tugboats instead of specialized vessels. Environmental loads were estimated with MOSES and AQWA, and frequency-domain analyses were performed to evaluate wave responses and towline tensions. Results showed that maximum tensions remained below both the Safe Working Load of towlines and the Effective Bollard Pull of tugboats during all spudcan lowering stages. Even under conservative OPLIM conditions, feasibility was confirmed. The findings indicate that the proposed tug-assisted method ensures adequate station-keeping capability while reducing cost, construction time, and weather dependency, presenting a practical alternative for large-scale OWT installation. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

18 pages, 5248 KB

Open AccessProject Report

Laboratory Testing to Assess the Feasibility of Polyurethane Flat Belts for Marine Energy Applications

by Justin Panzarella, Scott Jenne and Andrew Simms

J. Mar. Sci. Eng. 2025, 13(9), 1652; https://doi.org/10.3390/jmse13091652 - 28 Aug 2025

Cited by 1 | Viewed by 1141

Abstract

Polyurethane flat belts have received limited scientific attention as load-bearing elements in marine energy systems, particularly in applications involving dynamic tensile and bending loads. This study evaluates their potential as a replacement for traditional wire ropes in marine energy applications, with a focus [...] Read more.

Polyurethane flat belts have received limited scientific attention as load-bearing elements in marine energy systems, particularly in applications involving dynamic tensile and bending loads. This study evaluates their potential as a replacement for traditional wire ropes in marine energy applications, with a focus on their ability to be integrated into winch-driven wave energy converters where bending and tensile stresses can make long-term operation difficult. Polyurethane belts are hypothesized to offer enhanced fatigue resistance due to their reduced thickness in the bending plane and therefore lower bending stresses. This research involves a series of tests utilizing the National Renewable Energy Laboratory’s (NREL) Large-Amplitude Motion Platform to replicate the dynamic conditions experienced by mooring lines of winch-based point-absorber-type marine energy converters. The conditions tested include unequal coiling and uncoiling tensions and load cases resulting from the device’s unconstrained movement relative to its anchor, such as twisting and off-axis loading. Results from this study show that polyurethane flat belts can achieve more than 198 percent of the fatigue life of a conventional wire rope under similar load profiles. The stress concentrations resulting from off-axis loading and cumulative twist beyond the system’s allowable limits have been identified as potential failure modes for flat belt mooring lines used in winch-driven wave energy converters deployed in ocean environments. To mitigate these risks, the use of anti-spin systems and fairleads designed to accommodate off-axis loading while limiting twist accumulation is recommended. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

50 pages, 15489 KB

Open AccessArticle

Comparative Analysis of Scour in Riprap-Protected Monopiles and Hybrid Foundations

by João Chambel, Tiago Fazeres-Ferradosa, Mario Welzel, Francisco Taveira-Pinto and Pedro Lomónaco

J. Mar. Sci. Eng. 2025, 13(9), 1639; https://doi.org/10.3390/jmse13091639 - 27 Aug 2025

Cited by 2 | Viewed by 1620

Abstract

As the demand for new sustainable solutions for harvesting energy increases, the offshore energy sector focuses on optimising well-established state-of-the-art solutions while striving for new innovative approaches. Hybrid foundation designs have introduced new challenges and raised questions regarding scour and effective countermeasures. To [...] Read more.

As the demand for new sustainable solutions for harvesting energy increases, the offshore energy sector focuses on optimising well-established state-of-the-art solutions while striving for new innovative approaches. Hybrid foundation designs have introduced new challenges and raised questions regarding scour and effective countermeasures. To further improve the knowledge regarding scour prediction, this paper presents and analyses the results from an experimental study behaviour of a riprap protection system for a monopile that determines and characterises scour on a flexible arrangement of overlapping sub-areas. The study was complemented by a novel series of tests using a hybrid foundation, where an oscillating surge wave energy converter (OSWEC) type was coupled to the monopile. Despite being submitted to similar hydrodynamic conditions, distinct differences in the scour rate and damage number (S_3D) were observed for both models. Although the OSWEC type contributed to local wave height attenuation (up to a 30% reduction on the leeward side of the hybrid monopile), its oscillatory motion severely aggravated scour, with measured damage rates two to three times higher than those observed in isolated monopiles. These results raise relevant questions about the applicability of existing design formulas for scour protection and underscore the necessity for revised criteria tailored to hybrid offshore foundations. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

31 pages, 946 KB

Open AccessArticle

Performance Analysis of a Floating Seawater Desalination Structure Based on Heat Pipes

by Juan J. Vallejo Tejero, María Martínez Gómez, Francisco J. Muñoz Gutiérrez and Alejandro Rodríguez Gómez

Inventions 2025, 10(4), 72; https://doi.org/10.3390/inventions10040072 - 14 Aug 2025

Viewed by 1792

Abstract

This study presents a comprehensive numerical simulation and thermal performance analysis of a novel modular floating solar still system, featuring integrated heat-pipe vacuum tube collectors, designed for seawater desalination. This innovative system—subject of International Patent Application WO 2023/062261 A1—not only aims to enhance [...] Read more.

This study presents a comprehensive numerical simulation and thermal performance analysis of a novel modular floating solar still system, featuring integrated heat-pipe vacuum tube collectors, designed for seawater desalination. This innovative system—subject of International Patent Application WO 2023/062261 A1—not only aims to enhance efficiency and scalability beyond traditional solar stills, but also addresses the significant environmental challenge of concentrated brine discharge inherent in conventional desalination methods. The study evolved from an initial theoretical model to a rigorous dynamic thermal model, validated using real hourly meteorological data from Málaga, Andalusia, Spain. This modelling approach was developed to quantify heat transfer mechanisms and accurately predict system performance. The refined hourly simulation forecasts an annual freshwater production of approximately 174 L per unit. Notably, a preliminary economic assessment estimates the Cost of Produced Water per Litre (CPL) at 0.7509 EUR/litre, establishing a valuable baseline for future optimisation. These findings underscore the critical importance of dynamic hourly simulations for realistic performance prediction and validate the technical and preliminary economic feasibility of this novel approach. The system’s projected output, modular floating design, and significant environmental advantages position it as a promising and sustainable solution for freshwater production, particularly in coastal regions and sensitive marine ecosystems. This work provides a solid foundation for future experimental validation, cost optimisation, and scalable implementation of renewable energy-driven desalination. Full article

(This article belongs to the Topic Advancements and Challenges in Marine Renewable Energy and Marine Structures)

► Show Figures

Figure 1

Topic Menu

Topic Editors

Advancements and Challenges in Marine Renewable Energy and Marine Structures

Topic Information

Keywords

Participating Journals

Published Papers (14 papers)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI