An innovative approach for energy generation from waves

Sustainable energy generation is becoming increasingly important due to the expected limitations in current energy resources and to reduce pollution. Wave energy generation has seen significant development in recent years. This paper describes an innovative system for generating energy from wave power. A complete description of the system is presented including the general concept, configurations, mechanical design, electrical system, simulation techniques and expected power output of the system. The results from the hydraulic linear wave simulator, using a real wave profiles captured at a location in the UK using an ultrasound system, it was seen that a ±0.8 m wave at 10 s time period, produced a conditioned power output of approximately 22 kW at optimum load conditions for the tested 3-phase 44 kW permanent magnet generator type STK500. The results indicate that this new technology could provide an efficient and low cost method of generating electricity from waves

Ocean Energy in Belgium - 2019

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DFIG versus PMSG for marine current turbine applications

Emerging technologies for marine current turbine are mainly relevant to works that have been carried out on wind turbines and ship propellers. It is then obvious that many electric generator topologies could be used for marine current turbines. As in the wind turbine context, doubly-fed induction generators and permanent magnet generators seems to be attractive solutions to be used to harness the tidal current energy. In this paper, a comparative study between these two generators type is presented and fully analyzed in terms of generated power, maintenance and operation constraints. This comparison is done for the Raz de Sein site (Brittany, France) using a multi physics modeling simulation tool. This tool integrates, in a modular environment, the resource model, the turbine hydrodynamic model and the generators models

Electromagnetic rolling mass wave energy harvester for oceanic drifter applications

Ocean monitoring requirements have fomented the evolution of sensor platforms such as Lagrangian drifters, whose autonomy is a critical factor in the design process. Energy Harvesting (EH) has proven to be a sound option as an autonomous power source for sensor platforms. This paper deals with the design and simulation of a kinetic energy harvester (KEH) that captures energy from a drifter’s motion under wave excitation. This KEH is based on a rolling mass resonator with permanent magnets that oscillate with respect to a frame which includes a coil system. The induced current on the coil results from the relative motion of the rolling mass, whose natural frequency is tuned to match the drifter’s to achieve resonance. Preliminary simulations using OrcaFlex provide the motion vectors of the drifter, used to excite the KEH’s frame. A multi-body MSC.ADAMS model has been developed consisting of a simple DOF mass-spring-damper system that includes the frame motion and the electrical and electromagnetic models. Results provide an estimation of the power generated on a resistive load, showing 23 mJ harvested during a one-minute simulation.Postprint (author's final draft

State of the Art and Perspectives of Wave Energy in the Mediterranean Sea: Backstage of ISWEC

According to the European Commission, sea waves have a great potential as renewable energy source. Despite wave energy technology is a field in continuous development, it is not yet competitive with the other renewables, due to the small quantities of devices sold, most of them being prototypal solutions at level. So far, various Wave Energy Converter concepts have been developed and some of them tested in full scale. The most recurrent test environment is the North Atlantic Ocean, which possesses high energy potential. The Mediterranean Sea on the other hand is less energetic, but also possesses less dangerous extreme conditions. It represents a favourable starting point to develop technologies that later will be scaled up to more powerful sites. This article illustrates the wave energy potential of the Mediterranean and analyses the wave energy converters engineered according to sea states characteristic of the Mediterranean Sea. Focus is brought to the Inertial Sea Wave Energy Converter (ISWEC) technology, which is one of the few Mediterranean concept to have reached Technology Readiness Level (TRL) 7. The article will document the deployment and the following open sea test campaign of a full scale prototype off the shore of Pantelleria Island, Italy

Sustainability of the Renewable Energy Extraction Close to the Mediterranean Islands

The aim of this work is to explore the possibility of transitioning a fuel powered island to a renewable powered one. This transition is analyzed for the real MV/LV distribution system of the island of Pantelleria, in the Mediterranean Sea. Particularly, this work is focused on a renewable source nowadays totally unused: wave energy. Thanks to the innovative generator prototype designed by Department of Energy of University of Palermo (Italy), wave energy is able to represent a primary source for the production of electric energy in the Mediterranean islands. The procedures applied in the present article, as well as the main equations used, are the result of previous applications made in different technical fields that show a good replicability

Risk assessment for the installation and maintenance activities of a low-speed tidal energy converter

The study presented in this paper, is part of the Deep Green project, which includes the development of a power converter/device for employment in low-speed tidal currents. It mainly focuses on the initial steps to investigate the ways on how to minimize the risks during handling, operation and maintenance (O&M) activities of the full-scale device particularly in offshore operations. As a first tep, the full-scale device offshore installation and O&M tasks are considered. The overall risk analysis and decision making methodology is presented including the Hazard Identification (HAZID) approach which is complemented with a risk matrix for various consequence categories including personnel Safety (S), Environmental impact (E), Asset integrity (A) and Operation (O). In this way, all the major risks involved in the mentioned activities are identified and actions to prevent or mitigate them are presented. The results of the HAZID analysis are also demonstrated. Finally, the last section of this paper presents the discussion, conclusions and future actions for the above-mentioned activities regarding the full-scale device

The Desalination Process Driven by Wave Energy: A Challenge for the Future

The correlation between water and energy is currently the focus of several investigations. In particular, desalination is a technological process characterized by high energy consumptionnevertheless, desalination represents the only practicable solution in several areas, where the availability of fresh water is limited but brackish water or seawater are present. These natural resources (energy and water) are essential for each otherenergy system conversion needs water, and electrical energy is necessary for water treatment or transport. Several interesting aspects include the study of saline desalination as an answer to freshwater needs and the application of renewable energy (RE) devices to satisfy electrical energy requirement for the desalination process. A merge between renewable energy and desalination is beneficial in that it is a sustainable and challenging option for the future. This work investigates the possibility of using renewable energy sources to supply the desalination process. In particular, as a case study, we analyze the application of wave energy sources in the Sicilian context.Univ Palermo UNIPA, Dept Energy Informat Engn & Math Models, I-90128 Palermo, ItalyUniv Fed Sao Paulo UNIFESP, Dept Ciencias Exatas & Terra, BR-09910720 Sao Paulo, BrazilDepartament of Ciências Exatas e da Terra, Universidade Federal de São Paulo (UNIFESP), Sao Paulo 09910-720, BrazilWeb of Scienc

An Up-to-Date Technologies Review and Evaluation of Wave Energy Converters

International audience– The potential of electric power generation from marine renewable energy is enormous. Ocean waves are being recognized as a resource to be exploited for the sustainable generation of electrical power. The high load factors resulting from the fluid properties and the predictable resource characteristics make ocean waves particularly attractive for power generation and advantageous when compared to other renewable energies. Regarding this emerging and promising area of research, this paper presents a complete review of wave energy technologies describing, analyzing and fixing many of the concepts behind wave energy conversion. The proposed review will specifically highlights the main wave energy conversion projects around the world at different levels (demonstration stage, in production, and commercialized projects). In particular, mooring will be discussed, as it is a key feature behind massive deployment of wave energy converters. Finally, a discussion will highlight challenges that wave energy converters need to overcome to become commercially competitive in the global energy market. Nomenclature WEC = Wave Energy Converter; PTO = Power TakeOff ; P w_f = Power per meter of wave front; P w_mcl = Power per meter crest length; ρ = Water density (approximately 1000 kg/m 3); g = Gravity acceleration; A = Wave amplitude; T = Wave period