Hydrodynamic Behavior of Overtopping Wave Energy Converters Built in Sea Defense Structures

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 3 ◽

10.1115/omae2010-20372 ◽

2010 ◽

Author(s):

Lander Victor ◽

Jens Peter Kofoed ◽

Peter Troch

Keyword(s):

Wave Energy ◽

Sea Water ◽

Wave Climate ◽

Wave Flume ◽

Wave Energy Converters ◽

Physical Model Tests ◽

Vertical Walls ◽

Linear Slope ◽

Energy Converters

Many sea defense structures need to be adapted to the rising sea water level and changing wave climate due to global warming. The accordingly required investments open perspectives for wave energy converters (WECs) — that are built as part of the sea defense structures — to become economically viable. In this paper the average overtopping discharges q of overtopping wave energy converters built in sea defense structures are studied. Physical model tests with this type of devices have been carried out in a wave flume leading to experimentally determined values for the average overtopping discharge q. These experimental data are compared with predicted average overtopping discharges using existing empirical formulae from literature — derived mainly for sea defense structures. Overtopping WECs have small relative crest freeboard heights and smooth slopes to maximize overtopping, which is contradictive to the basic role of sea defense structures. As a consequence, the experimentally achieved average overtopping discharges are situated in a range that is not well covered by the existing traditional prediction formulae. The presented results for linear-slope overtopping WECs fill the gap between those for smooth dikes and those for plain vertical walls. The overtopping behavior in that particular range is discussed in this paper.

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Wave Energy Assessment at Valencia Gulf and Comparison of Energy Production of Most Suitable Wave Energy Converters

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17228473 ◽

2020 ◽

Vol 17 (22) ◽

pp. 8473

Author(s):

Raúl Cascajo ◽

Emilio García ◽

Eduardo Quiles ◽

Francisco Morant ◽

Antonio Correcher

Keyword(s):

Renewable Energy ◽

Wave Energy ◽

Energy Demand ◽

Alternative Energy ◽

Average Energy ◽

Wave Climate ◽

Energy Output ◽

Renewable Sources ◽

Wave Energy Converters ◽

Energy Converters

Seaports’ energy strategy should rely on the use of renewable energy. Presently, the share of renewable energy used by many of the ports worldwide is negligible. Some initiatives are in the process of implementation to produce some of the energy used by the Port of Valencia, one the largest ports in the Mediterranean Basin. Among these initiatives, a photovoltaic plant with an installed capacity of 5.5 MW is under a tendering process and the assessment studies for the deployment of three to five windmills are close to being finished. However, this is not enough to make it a “zero emissions port” as some of the energy demand would still be covered by fossil fuels. Therefore, we should consider clean alternative energy sources. This article analyses the wave energy resources in the surroundings of the Port of Valencia using a 7-year series of data obtained from numerical modelling (forecast). The spatial distribution of wave power is analysed using data from 3 SIMAR points at Valencia Bay and is compared to the data obtained by the Valencia Buoy I (removed in 2005). The obtained results are used to estimate the power matrices and the average energy output of two wave energy converters suitable to be integrated into the port’s infrastructure. Finally, the wave energy converters’ production is compared to the average amount of energy that is forecast to be obtained from other renewable sources such as solar and wind. Due to the nature of the Gulf’s wave climate (mostly low waves), the main conclusion is that the energy obtainable from the waves in the Valencia Gulf will be in correlation with such climate. However, when dealing with great energy consumers every source of production is worthwhile and further research is needed to optimize the production of energy from renewable sources and its use in an industrial environment such as ports.

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The effect of arrays of wave energy converters on the nearshore wave climate

Ocean Engineering ◽

10.1016/j.oceaneng.2018.11.043 ◽

2019 ◽

Vol 172 ◽

pp. 373-384 ◽

Cited By ~ 6

Author(s):

Reduan Atan ◽

William Finnegan ◽

Stephen Nash ◽

Jamie Goggins

Keyword(s):

Wave Energy ◽

Wave Climate ◽

Wave Energy Converters ◽

Energy Converters

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Parametric Evaluation of the Performance Characteristics of Tight Moored Wave Energy Converters

24th International Conference on Offshore Mechanics and Arctic Engineering: Volume 2 ◽

10.1115/omae2005-67338 ◽

2005 ◽

Cited By ~ 1

Author(s):

Spyridon A. Mavrakos ◽

Georgios M. Katsaounis

Keyword(s):

Wave Energy ◽

Wave Climate ◽

The Body ◽

Performance Characteristics ◽

Hydrodynamic Characteristics ◽

Wave Forces ◽

Diffraction Radiation ◽

Climate Conditions ◽

Wave Energy Converters ◽

Energy Converters

The paper aims at presenting a numerical model to predict performance characteristics of tight moored vertical axisymmetric wave energy converters that are allowed to move in heave, pitch and sway modes of motion. The hydrodynamic characteristics (exciting wave forces, hydrodynamic parameters) of the floats are evaluated using a linearized diffraction–radiation method of analysis that is suited for the type of bodies under consideration. According to this method matched axisymmetric eigenfunction expansions of the velocity potentials in properly defined fluid regions around the body are introduced to solve the respective diffraction and radiation problems and to calculate the floats’ hydrodynamic characteristics in the frequency domain. Based on these characteristics, the retardation forcing terms are calculated, which account for the memory effects of the motion. In this procedure, the coupling terms between the different modes of motion are properly formulated and taken into account. The floating WEC is connected to an underwater piston that feeds a hydraulic system with pressurized fluid. Numerical results showing parametrically the performance characteristics in terms of the expected power production for several types of floats that are exposed to the wave climate conditions commonly encountered in the Mediterranean area are presented and discussed.

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