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This paper runs forecasting experiments for wave energy over a range of 22 sites worldwide. The wave parameters are derived from physics-based model simulations. In order to better represent the sea state variability, the model values are embedded in noise drawn from several distributions, with seasonal weights, based on wave buoy data. Converter matrices are used to calculate the power output…

Global warming and high oil price have made the world to look into renewable energy like solar, wind, fuel cells etc. A massive amount of energy is released in the process of mixing of water of different salinity. This process is known as reverse electrodialysis. In this method, the production of electricity is free from thermal pollution, no output of pollutant, no radioactive waste. The…

The tidal current turbine is the most efficient way to extract energy from the sea. This system can be prone to critical loads such as impact accidental in the installation and maintenance phase. Indeed, several complex modes of damage susceptible to harming the stability of the structure are studied to conceive hybrid composite nozzles with better resistance to damage. For this reason, two…

Wave Energy Scotland has investigated some alternative methods of electricity generation from the motion of the waves. This technical note highlights the motivation for this, what the opportunities are and what challenges remain.

TC 114 - Marine energy - Wave, tidal and other water current converters - Part 4: Specification for establishing qualification of new technology

IEC TS 62600-4:2020 specifies the requirements of the technology qualification process for marine renewable technologies. Technology Qualification is a process of providing evidence and arguments to support claims that the…

This paper addresses the sizing and design problem of a permanent magnet electrical machine power take-off system for a two-body wave energy converter, which is designed to support ocean sensing applications with sustained power. The design is based upon ground truth ocean data bi-spectrums (swell and wind waves) from Martha’s Vineyard Coastal Observatory in the year 2015. According to the…

Performance characterization of oscillating water column (OWC) wave energy converters (WEC) is commonly assessed by conducting physical scale model experiments of OWC models fitted with orifice plates to the air chamber to both; simulate the power take off (PTO), and measure the air flow rate. Generally it is assumed that a single calibration factor can be used for bi-directional air flow…

The mooring system of floating wave energy converters (WECs) has a crucial impact on power generation efficiency, cost of delivered energy, proper operation, reliability and survivability. An effective design, addressing such competing objectives, requires appropriate mathematical models to predict mooring loads and dynamic response. However, conversely to traditional offshore engineering…

Wave energy is among the many renewable energy technologies being researched and developed to address the increasing demand for low-emissions energy. The unique design challenges for wave energy converter design—integrating complex and uncertain technological, economic, and ecological systems, overcoming the structural challenges of ocean deployment, and dealing with complex system dynamics—…

This paper presents a theoretical solution for the dynamic stability of the ocean current turbine system developed in Taiwan. This system is tethered to the sea floor and uses the Kuroshio Current to produce electricity. To maintain the performance of the turbine system in the presence of the Kuroshio Current, the stability of the surfaced turbine needs to be considered. The proposed system is…

Mathematical models are essential for the design and control of offshore systems, to simulate the fluid–structure interactions and predict the motions and the structural loads. In the development and derivation of the models, simplifying assumptions are normally required, usually implying linear kinematics and hydrodynamics. However, while the assumption of linear, small amplitude motion fits…

During the optimization phase of a wave energy converter (WEC), it is essential to be able to rely on a model that is both fast and accurate. In this regard, Computational Fluid Dynamic (CFD) with Reynolds Averaged Navier–Stokes (RANS) approach is not suitable for optimization studies, given its computational cost, while methods based on potential theory are fast but not accurate enough. A…

This paper analyses the numerical outcome of applying three different well-known mooring design approaches to a floating wave energy converter, moored by means of four catenary lines. The approaches include: a linearized frequency domain based on a quasistatic model of the mooring lines, a time domain approach coupled with an analytic catenary model of the mooring system, and a fully coupled…

Absorbing wave power from oceans for producing a usable form of energy represents an attractive challenge, which for the most part concerns the development and integration, in a wave energy device, of a reliable, efficient and cost-effective power take-off mechanism. During the various stages of progress, for assessing a wave energy device, it is convenient to carry out experimental testing…

This paper presents a novel method to extract energy from tidal currents by using a permanent magnet linear synchronous generator for an  scillating hydrofoil. In this work, an initial design of a linear generator is proposed for a biomimetically inspired oscillating hydrofoil system as a tidal energy generator. The device is designed to manipulate the flow stream and contained energy. It…

Marine current turbines (MCTs) has progressively attracted wider interest from the industry and many research initiatives due to its potential as a novel world energy resource. However, several technological issues amongst others fault detection of MCT blades still require further progress for their successful implementation. Indeed, power generation is likely to progressively degrade due to…

Fossil fuel is scanty and negatively affects the earth by inducing climate change. As a result, alternative and renewable energy (RE) sources are being investigated to replace fossil fuel. Wind and solar energy are leaders in the RE market, but huge and accessible other energy sources such as salinity gradient power (SGP) exist and need to be collected to contribute to the global energy demand…

One approach to support floating tidal current turbines is by using a moored catamaran, a barge type platform. Considering its low draft, one might expect that it performs best at typical straits with sea states of small wavelets to small waves. The problem is that the high rotational motion responses of the catamaran due to wave loads tend to reduce the turbine performance. This paper looks…

The development of wave power generation has been carried out since the 1790s. The technology involves capturing the energy of the wave using an actuation mechanism and converting it into useful work. Over the years many kinds of wave energy converters have been designed with varying rates of success. Novige has redesigned the buoy to a rectangular form thereby increasing the wetted area…

A numerical model for the optimization of the performance of an innovative overtopping breakwater for wave energy conversion is proposed. The model is based on the stochastic description of the overtopping phenomenon based on the results of extensive laboratory tests, and it is able to simulate the behavior of the device operating under any assigned sequence of sea states, thus allowing to…