There is a continuing and increasing need to develop renewable energy technologies that are efficient, cost-effective and produce usable forms of energy. Wave energy converters (WECs) have an opportunity to play a key and significant role in the integration of renewable energy technologies on a commercial scale.
It is estimated...
The world's oceans contain tremendous renewable energy potentials. It is estimated that if 0.2% of the ocean's untapped energy could be harnessed, it could provide power sufficient for the entire world [1]. This thesis provides a comprehensive description of the state-of-the-art of ocean energy extraction technologies and lessons learned from...
A significantly untapped renewable energy source exists in the world's oceans. It is estimated that if 0.2% of the ocean's untapped energy could be harnessed, it could provide power sufficient for the entire world. Ocean energy extraction is an old concept, and it is currently seeing the benefit of advancing...
Presented is an investigation into the modeling, active control design, and simulation of a generic horizontal pendulum wave energy converter, known as a PWEC. A description is provided of the dominant attributes PWECs have, showcasing their promising potential as wave energy converters. Seeking to further promote this potential, an active...
The substantial wave energy resource of the US Pacific Northwest (i.e. off the coasts of Washington, Oregon and N. California) is assessed and characterized. Archived spectral records from ten wave measurement buoys, operated and maintained by the National Data Buoy Center and the Coastal Data Information Program, form the basis...
Resulting from the action of wind over open water surfaces, water waves contain colossal amounts of energy that has not yet been harnessed. Seen as a very promising source for renewable energy generation, many studies have tried to make wave energy a cost competitive source by investigating optimal designs of...
This report deals with the current status of four promising
sources of electrical energy generation from the oceans. They
are, in sequence;
Ocean Thermal Energy Conversion: Where energy is obtained by
exploiting the temperature differences between warm surface
waters, and much deeper colder waters.
Tidal Energy: Where differences in water...
This paper describes a method for measuring nearshore ocean wave characteristics with a land-based, long-period vertical seismometer. The wavemeter system has proven to be highly reliable and produces continuous wave observations at low cost. It is now operational at six Coast Guard stations along the Oregon and Washington coasts; data...
Observations between 20 and 40 m depth were made with a towed thermostor
chain in the North Pacific. Despite the rapid vertical variation
of buoyancy frequency, spectra of isotherm displacements are in fair
agreement with other observations and with the Garrett-Munk model. The
spectra show evidence of a shoulder and...
The eventual deployment of wave energy converters (WECs) on a commercial scale will necessitate the grouping of devices into arrays or "wave farms," in order to minimize overhead costs of mooring, maintenance, installation, and electrical cabling for shoreward power delivery. Closely spaced WECs will interact hydrodynamically through diffracted and radiated...
The response on the continental shelf of a baroclinic ocean to
driving by an alongshore coastal wind stress and by barotropic and
baroclinic wind forced interior motions is studied as a function of
latitude. The relative excitation of continental shelf waves and
internal Kelvin waves is studied.
The response of...
The central Oregon coast was selected as an ideal site for wave energy
development and establishment of the Pacific Marine Energy Center (PMEC). PMEC will consist of two nearshore sites, one north (NETS) and one south (SETS) of the Yaquina River, Oregon. Our study aims to assess how the development...
Renewable energy resources, such as wind, solar, and wave, have a number of advantages compared to traditional fossil fuels. Numerous studies attest to the physical potential for wave energy development in Oregon. In transitioning from conventional fossil fuel to alternative energy provision, citizen understanding of the global energy problems and...
Wind energy is a cornerstone to the world of renewables. It is widely used in many parts of the world as a clean and effective form of power generation. However, wind power has a number of drawbacks, which limits its use in many regions. Solar power has been used not...
Oregon’s coastal communities grew from the booming logging and fishing industries of the 19th century, but in recent decades have faced not only major declines in both timber and fish resources but also an increasing reliance on tourists and retirees and the resultant glut of seasonal service-sector jobs. As a...
On July 9th, the Pacific Marine Energy Center (PMEC) and PacWave hosted national and international experts from government, academia and industry, and across maritime sectors, to explore future research and testing opportunities associated with the development of the PacWave testing facilities. This report summarizes the findings from the strategic break-out...
Underwater monitoring and manipulation with autonomous underwater vehicles (AUVs) are active avenues of research in the Field Robotics Community. The purpose of this document is to briefly summarize some of the more promising research applications as well as provide information from four companies working in the area of marine renewable...
Wave energy is emerging as a new potential source for renewable energy generation. However, wave energy technology is not currently cost competitive with other more mature renewable energy sources such as wind and solar. One approach that researchers and developers are taking to reduce the cost of wave energy is...
Oregon State University conducted a series of laboratory experiments to measure and quantify the near-field wave effects caused within arrays of Wave Energy Converters (WEC). As the waves and WECs interact, the WECs generate radiated waves; these effects vary with the location within the array. Analyzing the near-field waves will...
Ocean Wave Energy Converters (WECs) operating on the water surface are subject to storms and other extreme events. In particular, high and steep waves, especially breaking waves, are likely the most dangerous to WECs. A method for quantifying the breaking severity of waves is presented and applied to wave data...
Wave energy research and development has been ongoing in Oregon for at least two decades. Substantial interest started in the early 2000’s, flattened in the 2010’s, and is on the rise again. The Oregon wave energy sector recently experienced several sizable developments in 2020 and 2021, making this a critical...
Much like wind energy in its early years, marine energy has vast potential, and wave energy converter (WEC) concepts are constantly in development. Consequently, wave energy faces many challenges for expansion and has a wide-ranging design space of WEC concepts. The large design space demands new methods for understanding the...
Wave energy has the potential to power large and small factions of economies around the world alike. Current methods for determining the amount of wave energy resource available to wave energy converter (WEC) devices entail capturing the look of the sea state at large by presenting characteristic wave heights, periods,...
The Pacific Northwest of the United States is characterized by one of the greatest annual mean wave power resources in the world. As a result, the wave energy resource offshore of Oregon has been characterized, through hindcast models and physical buoy data, throughout the past decade. Over the past 8...
North America’s West Coast represents some of the highest global potentials for wave energy output. We developed and conducted a survey of a sample of residents (N=2000) in California, Oregon, Washington and British Columbia matched on gender, age, race, and education to the general population. Respondents were asked how much...
Surface waves play a vital role in air-sea interactions, and being able to easily measure them in-situ validates and improves predictive models. Here, we diagnose surface wave properties in the Bay of Bengal using modified vertical SOLO II profiling floats, which are regularly used as part of the Argo ocean...
Realizing the vast amount of energy available in ocean waves, an industry has emerged that is progressing towards the deployment of grid–connected wave energy converters. Likely to be deployed in arrays, a challenge to the wave energy industry is maximizing the energy production of such arrays. We have been developing...
Abstract— A highly idealized model of an ocean-fjord system, in which the tide is forced astronomically by the gravitational force of the moon, is used to study effects of localized tidal energy extraction on regional and global tides. The modeled system is energetically complete in the sense that the model...
The potential for electric energy generation from ocean waves is substantial and much research is being conducted on the conversion process as a renewable, grid-connected, power source. Some of the same attributes that make wave energy harvesting attractive as a grid-connected source also make it attractive as a remote, or...
Ocean waves propagating over cohesionless seabed deposits
produce cyclic shear stresses within the deposit. Under certain
conditions these stresses may cause a progressive build-up of pore
pressure. Pore pressure accumulation can result in liquefaction or
a substantial decrease in the effective stress with attendant large
deformations of the seabed deposit....
Hydraulic power take-off (PTO) systems have been implemented in several wave energy converter (WEC) designs in recent years. Two popular hydraulic PTO configurations coupled to a point absorber hydrodynamic model are simulated in waves representative of an energetic sea state likely to be found in deep waters off the coast...
This thesis presents an examination of the nearshore wave bottom boundary layer
under conditions of significant sediment response. Using both field observations and
simple models, the response of the bottom boundary layer to random waves is shown to
have a complex behavior. First, the linearized wave bottom boundary layer governing...
A linearized model with two vertical modes has been developed to understand observed characteristics of monthly variability in the Equatorial Pacific from TOPEX/POSEIDON measurements of Sea Surface Height (SSH). The 2-mode model is obtained from an equatorial beta plane model that has been linearized about a geostrophically balanced mean flow...
Wave energy conversion is still in its infancy, and in order for it to become a commercially viable technology, developers, investors and utilities need to estimate a Wave Energy Converter's (WEC's) performance for the wave climate of a potential installation site. With the goal of estimating a design's power output...
This thesis presents the details of a large-scale laboratory experiment to study the
turbulence generated by waves breaking on a fixed barred beach. The data set includes
comprehensive measurements of free surface displacement and fluid velocity for one
random and one regular wave case.
Observations of the time-averaged turbulent kinetic...
We investigate, theoretically and experimentally, the problem of modeling depth-integrated (2DH) surf zone circulation on an alongshore-nonuniform natural beach, with waves approaching from an arbitrary angle. An approximate theoretical model is developed, which captures the important effect of advection in the alongshore dynamics, and shows that a nondimensional parameter Re[subscript]s...
Wave-induced circulation is the defining characteristic of the nearshore. Within this region, the constant feedback cycle between incoming waves, wave-generated currents, and the mobile sediment bed is responsible for the evolution of complex patterns in nearshore and beach morphology. Central to our understanding of this system is knowledge of the...
Radiation stresses, defined as the excess flow of momentum due to the presence of waves (Longuet-Higgins, 1964), are the main drivers behind the cross-shore and longshore forcing that results in wave setup, set-down, and longshore currents (e.g. Svendsen, 2006). Longshore currents entrain and transport sediment and therefore play an important...
Ocean testing of Wave Energy Converter (WEC) prototypes is necessary to facilitate commercial WEC development. The Ocean Sentinel Instrumentation Buoy, completed in August 2012, provides a stand-alone load for WEC prototypes during ocean testing. The first part of this work was to develop the power conversion and data acquisition equipment...
This thesis investigates the effects of wave energy converters (WECs) on water waves through the analysis of extensive laboratory experiments, as well as subsequent numerical simulations. Data for the analysis was collected during the WEC-Array Experiments performed at the O.H. Hinsdale Wave Research Laboratory at Oregon State University, under co-operation...
A sharp temperature front, oriented along the south-west corner of the leading edge of a Tropical Instability Wave (TIW) warm trough, was encountered at 0°N, 140°W on November 2, 2008 and detected by a 0.45°C increase in SST that occurred over 7 s. The distinct SST signal was observed at...
Caissons on permeable seabeds have been designed and constructed
for a variety of needs in coastal and offshore engineering. An evaluation of the adequacy of the foundation beneath the structure is
required for an economic and safe design. To address this requirement, a two-dimensional analytical model of the foundation response...
A theory is developed to provide an analytical solution to an
unsteady flow field which is partially occupied by a porous structure.
The flow is induced by a small amplitude incident wave
train. The porous structure may contain multi-layer anisotropic but
homogeneous media. Three typical porous structures are investigated:
a...
Development of wave and offshore wind-based marine renewable energy is anticipated on the Outer Continental Shelf (OCS) off Oregon and much of the Pacific Northwest in the coming decade. Multiple issues related to environmental considerations and information needs remain for these emerging industries. The Oregon Marine Renewable Energy Environmental Science...
A field experiment designed to test the hypothesis that infragravity and lower frequency waves influence the patterns of erosion and deposition on the beach foreshore has been carried out. The data show coherent fluctuations in the foreshore sediment level which can be related to low frequency wave motions. The fluctuations...
The performance of the power take-off (PTO) system for a wave energy converter (WEC) depends largely on its control algorithm. This paper presents an adaptive damping control algorithm that improves power capture across a range of sea states. Validation for the numerical model was performed using data from two sources;...
Knowledge of wave conditions in nearshore regions supports the development of
ocean wave energy technology by providing wave climatology for device design
considerations, and power output estimates. By modeling wave transformation
over the continental shelf, wave conditions were predicted in nearshore regions
where potential wave energy conversion sites are located....
The reliability and survivability of a wave energy converter (WEC) is highly dependent on the variability and non-linearity of the ocean itself. Ocean variability occurs on many time scales. Climate variability occurs decade-to-decade, and year-to-year in the number and intensity of winter storms. Seasonal variation of wave height and period...
Ocean wave energy converter technology continues to advance and new developers continue to emerge, leading to the need for a general design, modeling, and testing methodology. This work presents a development of the process of taking a wave energy converter from a concept to the prototype stage. A two body...
The Coordinated Eastern Arctic Experiment (CEAREX) was a multi-platform geophysical study covering the period from winter 1988 to spring 1989 in the vicinity of the Yermak Plateau and Fram Strait. The Oceanography ("0") Camp component of CEAREX was designed to study the physical oceanographic conditions from the deep Nansen Basin...
This report presents moored observations of velocity, temperature, and conductivity
made at the "0" Camp during CEAREX (Coordinated Eastern Arctic Experiment).
The measurements were made in the Arctic Ocean, near 83 ON and 5 ° to 11 °E, from
sensors suspended below the ice during March-April 1989.
The circular wave basin provides a means of physically modeling the nearshore
without the typical problems associated with end walls. Three different coastal
processes were examined to demonstrate the use of a spiral wavemaker in a circular
wave basin. These were longshore currents, shear waves, and groin circulation. A
beach...
This dissertation has focused on the charateristics of bubbles generated by breaking waves and the feedback of wave-current interaction on the forcing mechanism of low frequency wave especially basin seiching wave. For the first study, Optical image capture observations of breaking waves in a laboratory surf zone are presented. The...
This repository item contains the files needed to reproduce the results reported in the published work entitled "Runups of unusual size: rogueness and variability of swash" in the Journal of Geophysical Research. As described in the publication, the results described within it pertain to simulations of wave runup for various...
Recently, there has been peaked interest in developing high energy producing and optimized power take-off topologies for Wave Energy Converters (WEC). As large as the potential of the oceans may seem, harnessing that energy and effectively converting it to electricity in significant amounts is a challenge. Currently, there are no...
This study presents a methodology for power take off (PTO) forecasting for an array of heave wave energy converters (WECs). Based on spectral data obtained directly from the National Data Buoy Center, representative realistic sea states are generated at the location of the WECs, and by using two wave-structure interaction...
Directional wave spectra have been estimated in this study based
upon simultaneous subsurface measurements of current and pressure.
Two previously developed methods, the stochastic and deterministic
approaches, have been reviewed and restudied. It is demonstrated by
means of the Correlation Theorem that the stochastic and deterministic
approaches are, under certain...
In 1996, Beach et al. first proposed the idea of mounting an echo-sounder on a Waverunner to measure nearshore beach profiles. This thesis discusses the Coastal Profiling System, an extension of the original work, which has been utilized to measure nearshore bathymetry at selected sites along the coasts of North...
Ocean wave energy has great potential to develop into a strong and reliable form of renewable energy. As the technology develops, more wave energy converters will be grid interconnected and the variable nature of the ocean will begin to influence the stability of the electrical grid system. There are many...
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Annette R. von Jouanne
Oceanwaveenergy has great potential to develop into a strong
Ocean wave energy shows great potential as a developing form of renewable energy. However, challenges arise in maturing this technology to achieve cost-effective energy conversion. Development and testing of wave energy converters can be problematic due to the harsh environment in which they are operated. To promote development of this...
Beach response to overwash processes is a topic of significant importance. Two
particular aspects of this topic were chosen for detailed analysis: the distribution of
maximum wave runup elevations and the cross-beach celerity gradient of overwash bores
on natural beaches. Data were collected using both traditional nearshore instrumentation
and recently...
With the increasing effort to identify alternative methods of energy generation, extraction of ocean energy has gathered a large interest. Research and industry have begun considering wave energy as the next new alternative energy. The unique challenges of ocean energy requires a wave energy converter to be both robust and...
This report documents oceanographic and meteorological measurements made from instruments deployed on four moorings over the continental shelf west of Oregon, from spring through
summer, 1999. These moorings were a component of an observational and numerical modeling program to study the response of the coastal ocean to wind forcing.
The...
This report presents observations from moorings of temperature, conductivity
and pressure, made during the Arctic Internal Wave Experiment (AIWEX)
in March-April 1985.
The purpose of the temperature and conductivity measurements was to
provide time series from which inferences could be made about the vertical
displacement of the internal waves.
The Arctic Internal Wave Experiment (AIWEX) was designed to study the internal wave and microstructure fields in the Beaufort Sea in the early spring. A major goal of the experiment was to verify the hypothesis that the internal wave and microstructure fields beneath the ice are far less energetic than...
Commonly proposed ocean wave energy converters (OWEC) use inefficient and maintenance demanding intermediate hydraulic and pneumatic systems. We propose a novel rotary direct-drive OWEC that eliminates these intermediate stages. The new device employs a contactless force transmission system (CFTS) comprising a “piston” and a “cylinder” and a ball screw to...
Rip currents pose a serious danger to visitors of bathing beaches; they are also an important process in surf zone circulation. Haller et al. [2014] demonstrated that shore-based X-band radar can be used to compliment in situ measurements of rip currents. However, little is known of the underlying radar imaging...
The characterization of bathymetry and its time evolution is very important for both oceanographic science applications, and for societal reasons relating to coastal engineering
and development. Historically, the process of depth surveying has been costly and labor-intensive.
This is especially true in nearshore regions, hence a method that is both...
Waves are the primary input of energy in the nearshore region, and together with the currents forced through the transfer of momentum that occurs during the wave breaking process they are the principal mechanism for sediment transport in the nearshore. The basic physics of waves and currents are thought to...
The ocean off Oregon's coast is a busy place with many activities occurring that can sometimes be in competition or cooperation. Deciding how new uses fit with existing ocean uses is complex, but there are some tools available to help decision-makers. Generating energy from waves is an emerging ocean use...
Power generation has been an ever growing exigency since the invention of electric power. The world is gradually inching away from conventional generation toward renewable generation. Advancements in renewable energy generation have been at a steady positive pace over the past few decades with different resources developing to be feasible...
As the negative impacts of a fossil fueled electricity market are becoming more prevalent and destructive, the necessity for alternative energy techniques increases as well. However, before commercial implementation is underway, these alternatives must be assessed from three important perspectives: environmentally, economically, and socially, which are known as the three...
Wave energy converter (WEC) devices are complicated systems containing hydrodynamic, mechanical, and electrical elements. WEC design efforts are primarily focused in the time-domain, using frequency-based energy analyses and numerical problem solving approaches that are staples in hydrodynamic design efforts to form the basic information set used in these time-domain development...
With the ever-increasing demand and competition for global energy resources among nations, it is essential to explore and tap into various energy sources to reduce dependency on global markets. Renewable energy sources offer a significant opportunity to create localized and stable energy supplies. Ocean wave energy can be a promising...
This thesis contains a manuscript describing the implementation of a high resolution wave forecasting model for the coasts of Washington and Oregon. The purpose of this project was to advance the wave predictive capabilities of the states of Oregon and the southwest part of Washington by including the effects of...
Numerical model and assimilation experiments were conducted in the tropical Pacific Ocean to obtain a better understanding of the processes that control the cold tongue surface mixed layer temperature balance during August 1999 to July 2004. The numerical model was first applied to test two hypotheses (asymmetric background currents and...
This essay provides a snapshot of sustainability and acceptability of wave energy and eight other electricity-generating energy sources in Oregon. Since “sustainability” is an important point of view in decision-making, the paper is centered around the concept. Although there is no consensus on the definition of sustainability in the academic...
The design of mobile wireless devices has always focused on reducing power, area, and cost. This dissertation proposes two techniques that are leveraged to save power and area and therefore cost. The first techniques reduces the noise in the receiver and results in a relaxed power requirement. The second technique...
Forecasting of ocean waves over a short duration on the order of tens of seconds was approached with the optimization of wave energy conversion in mind. This study outlines the development of an artificial neural network model, specifically the Nonlinear Autoregressive Network with Exogenous Input (NARX), to predict a wave-by-wave...
With the need to integrate renewable energy sources into the current energy portfolio and the proximity of many population centers to an ocean coastline, it is pressing that marine energy systems, specifically wave energy converters (WECs), are evaluated as potential solutions for meeting energy needs. In order to best understand...
Wave Energy Converters (WECs) promise to be a viable alternative to current electrical generation methods. However, these WECs must become more efficient before wide-scale industrial use can become cost-effective. The efficiency of a WEC is primarily dependent upon its geometry and ballast configuration which are both difficult to evaluate, due...