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Due to the density of water, tidal turbine blades are subject to significantly greater stresses than wind turbine blades. Multiple blade failures occurred during prototype testing as a result of loading conditions and protracted exposure to seawater, which created a severe work environment. The structural integrity of tidal turbine blades is essential for long-term reliability and performance…

Biofouling is a significant problem that affects renewable energy marine structures (REMS), such as wind turbines and those designed for wave or tidal energy exploitation. Marine organisms, including algae, barnacles, and mollusks, attach themselves to the surface of these structures, which can lead to reduced efficiency and increased maintenance costs. In addition, biofouling can also cause…

A single-degree-of-freedom Wave Energy Converter (WEC) that harvests energy from heave and surge motion of waves in nearshore conditions has been designed. The device targets supplying energy to aquafarms and attaches to an existing structure. The device consists of a buoy that slides up and down with waves along a linear rail, with this linear motion converted into the high-…

In order for Wave Energy Converters (WECs) to become economically viable they will have to be installed closely together in so-called WEC arrays. When WECs are placed closely together they influence each other’s motion, which is challenging to implement in a numerical model. The accurate modelling of WECs in WEC arrays is crucial for their further development into cost-effective renewable…

As one of the promising renewable energies, ocean renewable energy (ORE) in the form of tidal energy can be extracted through a horizontal-axis tidal turbine (HATT). HATT performance relies on various environmental factors, including the presence of waves, shear flow, blockage, and submersion depth. Several studies have been conducted regarding the effects of such factors on HATT’s performance…

Aiming to design and develop an affordable integrated floating breakwater and wave energy converter (WEC) system that has high performance in power absorption and wave attenuation, a novel integrated floater with a half-airfoil bottom is proposed. The genetic algorithm combined with the boundary element method is employed to optimize the half-airfoil bottom surface represented by the class-…

A lack of natural resources drives the oil dependency in Pacific Island Countries and Territories (PICTs), hampering energy security and imposing high electricity tariffs in the region. Nevertheless, the Western Equatorial Pacific is known for its large Sea Surface Temperature (SST) and deep-sea water (DSW) temperature difference favorable for harvesting thermal energy. In this study, we…

Wave energy represents a promising and sustainable source of energy with substantial potential. To promote the utilization of wave energy resources as well as develop new wave energy converters (WECs) with application prospects, an innovative elastic capsule oscillating water column (EC-OWC) WEC is proposed, and an initial experimental investigation is conducted on the device.…

Wave energy is a promising actor for the renewable energy-mix that needs to be increasingly prominent worldwide. However, wave energy often remains too neglected in energy-mix studies. To avoid pre-selecting locations with potential underestimation of Wave Energy Converter performances, indexes and methods have been developed to pair wave energy converter(s) and locations, but (a)…

This paper presents a novel Control Co-Design (CCD) methodology aimed at economically optimising the layout of wave energy converter (WEC) arrays. CCD ensures the synergy of optimised WEC and array parameters with the final control strategy, resulting in a comprehensive and efficient design of the array. By integrating a spectral-based control strategy into the array layout design, this study…

Self-powered smart buoys are widely used in sustainable sea, such as marine environmental monitoring. The article designs a self-powered and self-sensing point-absorber wave energy converter based on the two-arm mechanism. The system consists of the wave energy capture module, the power take-off module, the generator module and the energy storage module. As the core component of the wave…

Local atmospheric conditions surrounding an off-shore Oscillating Water Column device — OWC hereinafter —, in particular wind action, may affect OWC performance and efficiency, specially over long harvesting intervals, i.e. yearly energy production. This work proposes an experimental study of a simple off-shore OWC where different ambient conditions are compared. More specifically, it proposes…

In this paper, solar energy is used as the auxiliary heat source of the ocean thermal energy radial inflow turbine, and the thermodynamic model of the circulation system is established. In addition, the ejector is introduced into the ocean thermal power generation system, and the process simulation is carried out using Aspen Plus V12. To address performance attenuation of the radial turbine…

Conversion of the ocean’s vertical thermal energy gradient to electricity via Ocean Thermal Energy Conversion (OTEC) has been demonstrated at small scales over the past century, and represents one of the largest (and growing) potential energy sources on the planet. Here we describe how OTEC could be modified to provide a large source of CO₂-emissions-negative energy while also…

Ocean Thermal Energy Conversion (OTEC) plants will employ the temperature difference (ΔT) between the solar-heated surface layer of a tropical ocean (24–29.5°C) and the water at 500–1200 m depth (7-3.5°C) as the source and sink for a Rankine cycle system to generate electric power. An annual average ΔT near 24°C is available to grazing tropical OTEC plants. The resource is tremendous in terms…

Marine renewable energy (MRE) is a label that embraces a range of technologies used to harness ocean energy, including wave, tidal stream, tidal barrage, ocean thermal energy conversion (OTEC) and salinity gradient, as well as offshore wind (floating and fixed). For the current analysis, floating solar is omitted from the MRE set. With an increasing drive towards zero-carbon energy provision,…

On behalf of Ocean Energy Systems (OES) and the U.S. Department of Energy, the Portal and Repository for Information on Marine Renewable Energy (PRIMRE) team, led by the National Renewable Energy Laboratory (NREL), Pacific Northwest National Laboratory (PNNL), and Sandia National Laboratories (Sandia), hosted the fourth international workshop to explore marine…

We investigate the performance of a novel power takeoff (PTO) featuring belt-arc speed amplification for oscillating surge wave energy converters (OSWECs), aiming to address the PTO design challenges of extremely low rotary speed and large torque under the low-frequency and large energy density ocean wave excitations. The belt-arc design significantly increases the rotary speed of the…