Showing papers on "Marine energy published in 2015"

Social and ecological impacts of marine energy development

Abstract: For marine energy to be truly sustainable, its social and ecological impacts must be identified and measures by which to mitigate adverse effects established before devices are deployed in large arrays To inform future research and encourage environmentally-sensitive developments, this review aims to identify the most significant social and ecological issues associated with wave and tidal current energy generation Modifications to wave climates, flow patterns, and marine habitats, particularly through increased underwater noise and collision risk, are identified as key ecological issues Social acceptance of renewable energy is found to be closely linked to the level of stakeholder involvement and the public perception of renewable energy The review concludes with a call for a more strategic and collaborative research effort between developers, academia, and the public sector to improve environmental monitoring standards and best practices for device and array design

Tidal power generation - A review of hydrodynamic modelling

Abstract: Extracting power from the tide is a potential avenue for renewable energy production but is also a significant engineering challenge. This challenge has many different aspects but the basic problem is the hydrodynamic problem of converting the movement of the ocean into mechanical power. This paper presents a review of some of the hydrodynamic modelling techniques which can be used to model tidal barrages and tidal turbines. The analysis of these is broken down into different length scales, ranging from a single device, to an array of devices, and up to regional scales. As well as discussing modelling techniques some of the hydrodynamic problems, such as resource assessment and efficiency of power generation, are discussed.

Evaluation and comparison of the levelized cost of tidal, wave, and offshore wind energy

Abstract: In the current context of environmental degradation and depletion of fossil fuels, marine energy has emerged as an alternative to traditional energy resources. However, being in an initial step of development, extracting energy from the ocean is often regarded as difficult and uneconomical. The existing models for assessing marine energy costs are often oversimplified, leading to uncertainties that may hold investors back and slow down the market penetration of this renewable. Therefore, an accurate prediction of marine energy costs is fundamental to drawing conclusions about its competitiveness. Among the different possibilities of marine energy, this paper focuses on the economic analysis of tidal, wave, and offshore wind energy. The individual costs involved in the construction of these offshore energy parks and operation and maintenance tasks during their lifetime are determined. With this information, the levelized cost (€/MW h) is calculated for offshore wind, wave and tidal energy (€165/MW h, €225/MW h and €190/MW h, respectively). It is found that these renewables have a higher energy cost than traditional energy sources; however, considering factors such as the learning rate or externalities enhances their competitiveness. In the second part of this paper, combined energy systems, such as hybrid converters, are presented as a future solution to boost the development of marine energies. The synergies between these renewables are outlined, as well as the cost savings that can be achieved through diversified energy systems.

Enhancing Wave Energy Competitiveness through Co-Located Wind and Wave Energy Farms. A Review on the Shadow Effect

Abstract: Wave energy is one of the most promising alternatives to fossil fuels due to the enormous available resource; however, its development may be slowed as it is often regarded as uneconomical. The largest cost reductions are expected to be obtained through economies of scale and technological progress. In this sense, the incorporation of wave energy systems into offshore wind energy farms is an opportunity to foster the development of wave energy. The synergies between both renewables can be realised through these co-located energy farms and, thus, some challenges of offshore wind energy can be met. Among them, this paper focuses on the longer non-operational periods of offshore wind turbines—relative to their onshore counterparts—typically caused by delays in maintenance due to the harsh marine conditions. Co-located wave energy converters would act as a barrier extracting energy from the waves and resulting in a shielding effect over the wind farm. On this basis, the aim of this paper is to analyse wave energy economics in a holistic way, as well as the synergies between wave and offshore wind energy, focusing on the shadow effect and the associated increase in the accessibility to the wind turbines.

Piezoelectric devices for ocean energy: a brief survey

Abstract: Piezoelectric materials directly convert strain energy into electric energy and vice versa and are commonly used in sensing and actuating applications. They have been employed in mediums frequently undergoing vibrations, allowing harnessing of power at a small scale. Ideas of using the piezoelectric effect as a power take-off mechanism for ocean energy emerged in the 1970s and are still at a developing stage. This article overviews recent development on the application of the piezoelectric processes to the ocean field and provides a building block for future research work of ocean engineers who are interested in such possibilities. A brief discussion on the selection of the piezoelectric materials for different ocean-engineering applications is presented. Significant research projects on ocean-energy extraction through the use of these materials are then described and discussed with special scrutiny on the viability of proposed designs and their experimental or numerical validation. Various harvesting techniques in an ocean environment are categorized and compared. The challenges ahead and the outlook for success in this area are outlined.

Offshore Energy Structures: For Wind Power, Wave Energy and Hybrid Marine Platforms

Abstract: If you are searched for the ebook Offshore Energy Structures: For Wind Power, Wave Energy and Hybrid Marine Platforms by Madjid Karimirad in pdf form, in that case you come on to the correct website. We present utter variant of this ebook in PDF, doc, txt, ePub, DjVu formats. You can reading Offshore Energy Structures: For Wind Power, Wave Energy and Hybrid Marine Platforms online by Madjid Karimirad either download. Therewith, on our website you can reading manuals and diverse artistic eBooks online, either download theirs. We will to draw on consideration what our website does not store the book itself, but we provide link to the website wherever you may download either reading online. So that if have necessity to downloading Offshore Energy Structures: For Wind Power, Wave Energy and Hybrid Marine Platforms by Madjid Karimirad pdf, then you've come to the correct website. We own Offshore Energy Structures: For Wind Power, Wave Energy and Hybrid Marine Platforms DjVu, txt, PDF, doc, ePub formats. We will be glad if you revert again and again.

Mathematical Modeling of Oscillating Water Columns Wave-Structure Interaction in Ocean Energy Plants

Abstract: Oscillating Water Column (OWC)-based power take-off systems are one of the potential solutions to the current energy problems arising from the use of nuclear fission and the consumption of fossil fuels. This kind of energy converter turns wave energy into electric power by means of three different stages: firstly wave energy is transformed into pneumatic energy in the OWC chamber, and then a turbine turns it into mechanical energy and finally the turbogenerator module attached to the turbine creates electric power from the rotational mechanical energy. To date, capture chambers have been the least studied part. In this context, this paper presents an analytical model describing the dynamic behavior of the capture chamber, encompassing the wave motion and its interaction with the OWC structure and turbogenerator module. The model is tested for the case of the Mutriku wave power plant by means of experimental results. For this purpose, representative case studies are selected from wave and pressure drop input-output data. The results show an excellent matching rate between the values predicted by the model and the experimental measured data with a small bounded error in all cases, so that the validity of the proposed model is proven.

Place Attachment and Marine Recreationists' Attitudes toward Offshore Wind Energy Development

Abstract: Offshore wind energy initiatives are increasingly prevalent and cited by developers and agencies as viable avenues to provide energy for a growing population, increase energy security, and mitigate global climate change (Devine-Wright, 2011; Pasqualetti, 2011). In 2010, the U.S. Department of the Interior (USDOI) released its "Smart from the Start" program intended to facilitate siting and construction of wind energy along the U.S. eastern seaboard. In 2012, the Bureau of Ocean Energy Management (BOEM) announced new wind energy leases in Maryland, Virginia, New Jersey, and Delaware (Clayton, 2012). Also in 2012, the largest offshore wind farm (102 turbines producing 367.2 megawatts) was launched in the United Kingdom (REM, 2012). The BOEM anticipates future commercial leases along the eastern seaboard and the USDOI reports a high commitment to continue initiatives that accelerate the siting, leasing, and construction of new offshore wind energy projects (Clayton, 2012).Public involvement processes aimed to assess project support from community stakeholders are standard in offshore wind energy planning and are often required prior to actual development (Ellis, Barry, & Robinson, 2007; Pasqualetti, 2011). Although these assessments employed varying methods (Devine-Wright, 2005), most studies used public opinion polling to identify the levels of acceptance for proposed projects within a community or region (Szarka, 2006). Often missing from these assessments are focused investigations into subpopulations that may be more sensitive to development or more affected by offshore wind energy development than the general public (Ellis, Barry, & Robinson, 2007). One relevant subpopulation is marine recreationists (e.g., boaters, anglers, beach users) because they may frequently use and enjoy the near shore waters proposed for turbine siting.Concurrently, many locations cited as "ideal" for offshore wind energy projects are close to important marine recreation resources, including tourism destinations (Gamboa & Munda, 2007). Marine recreationists engage in activities such as general beach use, boating, and angling in many of the areas proposed for offshore wind energy and often seek out these areas for their unique site attributes, such as unobstructed waters and viewsheds (Woosnam, Jodice, Von Harten, & Rhodes, 2008). For example, the Cape Wind project in Massachusetts proposed siting 132 turbines in the shallow waters of Horseshoe Shoal (Nantucket Sound; Firestone & Kempton, 2007), an area highly frequented by anglers and tourists (CCHFA, 2009). Additionally, people often return to nature-based recreation areas repeatedly to experience the benefits derived from recreation activities (Manning, 2011).Because of this repeated activity involvement in one location, recreationists often develop strong emotional and cognitive connections with a specific place (i.e., place attachment or place bonding; Hammitt, Kyle, & Oh, 2009). The strength and type of these bonds can lead to varying levels of acceptance for recreation resource management actions (Kyle, Graefe, & Manning, 2005), such as opposition and support for offshore wind energy development (Devine-Wright & Howes, 2010). Development action or even proposed wind energy projects may interrupt or potentially enhance these place-based bonds (Devine-Wright, 2009). Furthermore, high place attachment may lead to increased opposition or support for offshore wind energy, which could result in civic actions that could decrease or promote project success (e.g., voting, attending public meetings, writing opinion articles; Devine-Wright, 2005; 2009; Devine-Wright & Howes, 2010). Therefore, evaluating and identifying marine recreationists' levels of place attachment may help explain variation in their opposition and support for offshore wind energy, and their potential civic action in response to proposed projects.Although, offshore wind energy development is increasing, and its development often converges with marine recreation resources where place-based bonds develop, there are lim- ited investigations of marine recreationists' attitudes toward offshore wind energy development Furthermore, researchers have not created, tested, and validated scales to capture marine recreationists' levels of opposition and support for offshore wind energy development. …

In-stream hydrokinetic power: Review and appraisal

Abstract: The objective of this paper is to provide a review of in-stream hydrokinetic power, which is defined as electric power generated by devices capturing the energy of naturally flowing water—stream, tidal, or open ocean flows—without impounding the water. North America has significant in-stream energy resources, and hydrokinetic electric power technologies to harness those resources have the potential to make a significant contribution to U.S. electricity needs by adding as much as 120 TWh/year from rivers alone to the present hydroelectric power generation capacity. Additionally, tidal and ocean current resources in the U.S. respectively contain 438 TWh/year and 163 TWh/year of extractable power. Among their attractive features, in-stream hydrokinetic operations do not contribute to greenhouse gas emissions or other air pollution and have less visual impact than wind turbines. Since these systems do no utilize dams the way traditional hydropower systems typically do, their impact on the environme...

Survivability of Wave Energy Converter and Mooring Coupled System using CFD

Abstract: Engineering and Physical Sciences Research Council (EPSRC) via SuperGen UK Centre for Marine Energy Research (UKCMER)

Preface to Special Topic: Marine Renewable Energy

Abstract: Marine renewable energy (MRE) is generates from waves, currents, tides, and thermal resources in the ocean. MRE has been identified as a potential commercial-scale source of renewable energy. This special topic presents a compilation of works selected from the 3rd IAHR Europe Congress, held in Porto, Portugal, in 2014. It covers different subjects relevant to MRE, including resource assessment, marine energy sector policies, energy source comparisons based on levelized cost, proof-of-concept and new-technology development for wave and tidal energy exploitation, and assessment of possible inference between wave energy converters (WEC).

Emulation of an OWC Ocean Energy Plant With PMSG and Irregular Wave Model

Abstract: Ocean energy is a promising resource for renewable electricity generation that presents many advantages, such as being more predictable than wind energy, but also some disadvantages such as large and slow amplitude variations in the generated power. This paper presents a hardware-in-the-loop prototype that allows the study of the electric power profile generated by a wave power plant based on the oscillating water column (OWC) principle. In particular, it facilitates the development of new solutions to improve the intermittent profile of the power fed into the grid or the test of the OWC behavior when facing a voltage dip. Also, to obtain a more realistic model behavior, statistical models of real waves have been implemented.

Environmental Risk Evaluation System—an Approach to Ranking Risk of Ocean Energy Development on Coastal and Estuarine Environments

Abstract: The pressure to develop new and renewable forms of energy to combat climate change, ocean acidification, and energy security has encouraged exploration of sources of power generation from the ocean. One of the major challenges to deploying these devices is discerning the likely effects those devices and associated systems will have on the marine environment. Determining the effects each device design and deployment system may have on specific marine animals and habitats, estimating the extent of those effects upon the resiliency of the ecosystem, and designing appropriate mitigation measures to protect against degradation all pose substantial challenges. With little direct observational or experimental data available on the effects of wave, tidal, and offshore wind devices on marine animals, habitats, and ecosystem processes, researchers have developed the Environmental Risk Evaluation System (ERES) to provide preliminary assessments of these risks and to act as a framework for integrating future data on direct interactions of ocean energy devices with the environment. Using biophysical risk factors, interactions of marine animals and seabirds, with ocean energy devices and systems, are examined; potential effects on habitats, and changes in processes such as sedimentation patterns and water quality, are also considered. The risks associated with specific interactions for which data are more readily available are explored including interactions between ocean energy devices and surface vessels, toxicity of anti-biofouling paints, and potential for harm to animals from turbine blade strike. ERES also examines the effect that environmental regulations have on the deployment and operation of ocean energy devices.

National geodatabase of ocean current power resource in USA

Abstract: Ocean currents represent an alternative source of clean energy given their inherent reliability, persistence and sustainability. The general ocean circulation is characterized by large rotating ocean gyres resulting in rapid ocean currents along the western boundaries because of the Coriolis Effect. The Gulf Stream system is formed by the western boundary current of the North Atlantic Ocean flowing along the east coast of the United States, and is of particular interest as a potential energy resource for the United States. This study presents a national database of ocean current kinetic energy resource derived from seven years of numerical model simulations to help advance awareness and market penetration for ocean current energy. A web based GIS interface is provided for dissemination of the national energy resource data: http://www.oceancurrentpower.gatech.edu/ . The website includes GIS layers of computed monthly and yearly mean ocean current speed and associated power density along the coastlines of the United States, as well as joint and marginal probability histograms for current velocities at a variable horizontal resolution of 4–7 km. Various tools are provided for viewing, identifying, filtering and downloading the data from this website. The Gulf Stream system, especially the Florida Current, concentrates the highest kinetic power density ( > 2000 W / m 2 ). The majority of the kinetic power and its variability are only present in relatively shallow water given the strong correlation with the surface wind stress. The kinetic energy flux in the Florida Current is estimated over 30 years to provide temporal variability of the undisturbed kinetic energy with high statistical significance. Available power of approximately 5 GW associated with the undisturbed natural flow condition from the Gulf Stream system is predicted based on hypothetical turbine parameters. Successful development of renewable energy generation requires further studies to account for more precise technical, economic and environmental constraints.

Reference Model 5 (RM5): Oscillating Surge Wave Energy Converter

Abstract: NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof.