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A brief introduction to Ocean energy followed by an outlook on the wave energy potential around the globe and a comprehensive discussion on the distribution of wave energy potential along the coast of Indian peninsula are presented in this chapter. The wave energy distribution along the coastal region is expected to facilitate the understanding and planning process of installation of new energy devices. Further the importance of wave energy and its impact on the environment are reported.

Renewable energy technologies in OECD countries have been highly promoted for the purpose of producing cleaner energy and better life conditions for people in urban areas. However, developing countries require an additional extended analysis to assess the feasibility for their implementation, identify financial risks and settle emissions reduction. In Colombia, in the last several years, there have been more robust public policy strategies to expand alternative energy sources and accomplish the COP 21 limits of 20% GHG reduction before 2030. In this study, a methodology based on Multicriteria Decision Making Methods (MCDM), which is the result of a research project to assess comparatively new renewable energy technologies with renewable energy technologies currently used in the country based on technical, financial, and environmental criteria, has been developed. The methodology allows for the identification of the best and the worst alternatives from the output ranking, considering the numerical value of criteria placed on the decision matrix and the dominance index output. The methodology was tested to assess the comparison of ocean energy technologies in Colombia. Tidal range was identified as the best alternative and ocean current the worst, among the projects evaluated.

Nowadays, a variety of technical solutions to improve energy efficiency and reduce emissions is available to the shipping industry, offering a wide range of possible solutions to ship builders and operators. However, the selection of the best performing option is subject to the individual specifications of the vessel, its trade route, lifetime expectancy and many other factors. Furthermore, the decision-making process usually accounts for multiple objectives, such as energy efficiency, environmental impact, reliability and safety, which in various cases may be conflicting. This chapter demonstrates how Model Based Systems Engineering methods and associated tools can support the assessment and quantification of ship machinery system performance at concept design and in retrofit applications, aiding decision makers. Two typical application cases of the HOLISHIP project are presented: the energy efficiency and reliability assessment of a hybrid Offshore Supply Vessel; and the retrofitting of a bulk carrier with a fuel recovery from a sludge unit.

This chapter explores the basics of power, energy, their units, fossil fuels vs. renewable energy, and provides a short introduction to the various renewable energy technologies available today. The chapter concludes with a case study on some nations that have achieved or are very close to achieving a 100% renewable energy-powered energy profile, which means that they derive most of their energy from renewable energy sources.

There are many conventional ways of producing energy at large scales such as fossil fuels, hydroelectric power station, wind energy, solar cell plants, marine energy, etc., but most of these require bulky plantation, huge manpower, wide land occupation and are non-portable and expensive to handle too. In the twenty-first century, there is still a huge gap between worldwide energy supply and its demand. The advances in the technology sector have also increased the consumption of energy, but the sources of generating the renewable energy remain limited. In order to account for these problems in recent years, several methods have been adopted and a significant research in this direction has been made by the invention of the hydroelectric cell by Dr. R. K. Kotnala’s group in 2016. Instead of using the magnetic character in the ferrite nanostructures, these nanomaterials were first time effectively exploited for direct energy harvesting application by using their capability to dissociate the absorbed water molecules on its porous surface. This allows the production of ions, which is then followed by the charge transfer of hydronium, hydroxyl and hydrogen ions between the electrodes of the ferrite nanostructures and results in the generation of an electric current across the circuit. The concept of the hydroelectric cell is new, and these cells are easily portable, inexpensive, biodegradable and eco-friendly in nature. This chapter provides an insight on the concept of spinel ferrite nanostructures for the application in the hydroelectric cell.

Traditionally, the ocean and its ecosystems have been viewed as cost-free spaces to dispose of waste and a source of limitless resources, resulting in excessive use and, in some cases, irreversible change of marine resources and coastal areas. This chapter will first discuss the various challenges to the traditional ocean economy, including climate change, unsustainable fisheries and aquaculture, and marine pollution. The chapter will then discuss marine and coastal ecosystem degradation, biodiversity loss, degraded ecosystem services, impacts of marine energy systems, and COVID-19.

The development of renewable marine energy at sea is at the mind of the energy transition and blue growth in which France is committed. The domain includes the component manufacturing, assembly, installation and maintenance of the offshore wind farm (OWF). However, the global supply chain of the OWF is very complicated. This complexity is due to the size of wind turbine components. Indeed, this latter is very large: a total height of 150 m and a diameter of 120 m and therefore, require special handling and logistics. To avoid disruption of the global supply chain process of offshore wind, all aspects that can impact the latter must be analyzed. Disturbances can range from capacity problems to quality problems via different weather conditions. Between production and offshore installation phase, the supply chain includes onshore transportation, port handling and shipping. For example, any delay in supply will be fundamentally disrupting the production or installation process of the farm. The produced components from a wind turbine cannot be transported as standard components because they are for the most part very bulky and heavy. To take into account these specificities, transport can be made for example at night when it is possible to use exclusive roads. The purpose of this paper aims to realize a review of logistics planning for OWF operations. A classification according to strategic, tactical and operational decision of logistics planning for the OWF operations was conducted.

The aim of this chapter is to compare wave energy and offshore wind energy in economic terms. The future of energy and electricity production will be at ocean. In this sense, offshore wind and wave energy are the two main important offshore renewable energies. However, it is important to compare them in economic terms to calculate their feasibility in order to take strategic decisions. In this context, aspects such as the LCOE are calculated to provide an economic comparison of these two technologies. The methodology will be carried out for a particular case of study. The location selected for this purpose has the offshore wind resource, and the wave energy resource is very good: It is the region of Galicia (located in the northwest of Spain). Results indicate the best ocean renewable energy in economic terms. This comparison is useful for future considerations in order to select the best location for an offshore renewable energy farm.

Over the last decade, research on technologies to exploit tidal current kinetic energy for renewable electricity generation has had a significant growth. However, as to date, there is not a consensus worldwide on standard Power Take-Off (PTO) systems, due to the current immaturity of tidal energy converter technologies. In most cases, mechanical/electrical power conversion follows well-proven technologies derived by the mature wind-energy sector. However, the peculiarities of tidal energy resource impose ad hoc technology solutions. In this paper, different generator topologies and recent developments for marine tidal energy systems are reviewed and compared. The aim is to provide an overall perspective and identify areas for further development. Among considered technologies, the direct-drive permanent magnet synchronous generator by the full-rated frequency converter (FFC) represents an appealing solution, for reduced system complexity and maintenance requirements and possibility to develop smart Maximum Power Point Tracking (MPPT) strategies.

Renewable marine energy can be an important contributor to achieving the goal of CO2 reduction for 2050 established by the Kyoto protocol. However, the infrastructures that exploit renewable energy sources have a spatial impact on marine landscapes that must be taken into consideration. This impact determines public perception of renewable energy projects. This study analyses relevant case studies of marine energy infrastructure that have dealt with this impact from different disciplines. The objective of this work is to create an inventory of spatial solutions to the impacts generated in marine landscapes. This catalogue will be a useful tool for decision-making when facing a multidisciplinary process of marine spatial planning related with energy production. In order to be validated, the inventory must achieve the following goals: (i) encouraging multidisciplinary processes of comparison, (ii) enabling Research by design methodology (iii) addressing integration in landscape, (iv) awareness of socioeconomic and cultural values and (v) including data-informed results. Two impacts related to the field of landscape architecture in each collected sample have been considered relevant for this catalogue: visual impact and spatial footprint. Formal features and numerical indicators visually describe these impacts, as well as the innovative strategies that these projects propose to deal with them. These features are: element configuration (“anatomy”), stability systems and dynamic systems. They are represented by synthetic drawings. The chosen indicators are: energy output, distance to shoreline, sea depth, area of device, and height of device. These are included in a radial chart. In addition, a label with basic identification data has been attached to each sample. The quantitative information in the catalogue makes the different projects comparable, while the graphic representation give a qualitative point of view about the spatial consequences of this data. Both are necessary to promote future multidisciplinary marine energy projects.

Energy harvesting is systematic process and the main activity (solar energy harvesting, wind energy harvesting, ocean energy harvesting etc.) where a lot of energy is harvested and supplied to the main energy grid. Harvesting on the other hand means a bountiful process and systematic process and there is a major energy gain (100% activity). Energy harvesting technologies supply unlimited operating life of low-power equipment and even remove the need to replace batteries where it is costly, unfeasible, or unsafe. The performance of energy harvesting is fundamentally linked to the amount and nature of the source energy present in the environment. When designing an energy harvesting solution, knowledge of the application constraints and the details of the energy source have to be known in advance.

Energy is one of the critical issues that directly impact the economy, the environment, and the security of human beings. All energy technologies require materials; therefore, the types and amounts of materials consumed vary widely. While materials science and engineering are only one aspect of the response to the energy challenges, it primarily has a crucial part to play in creating the advanced energy systems. In the past, it has contributed significantly to advances in the safe, reliable, and efficient use of energy and available natural resources. Now materials research is being performed from structural materials, functional materials to high photon energies, which can offer promising solutions to achieve accessible, renewable, and sustainable energy pathways for the future. Particularly, the growing importance of environmental issues is such that energy generation, conservation, storage, and security of supply will continue to be major drivers for materials technology. Sustainable energy production and use are needed while at the same time meeting socioeconomic and environmental targets: The high priority of energy makes it important to sustain research, development, and modeling of materials for energy applications; the knowledge-base of high-integrity structural and functional materials should be recovered, captured, and developed for future power generation; transferable material solutions and methods across the complete energy portfolio should be examined to attain maximum efficiency and competitive advantages. With the advent of nanomaterials and innovative multifunctional materials, materials science and engineering is expected to play an increasing role in sustainable technologies for energy generation, storage, and distribution, as well as efficient utilization of future energy. Principal areas of advanced materials development include but not limited to sustainable structural and functional materials for fossil power, solar energy, wind energy, geothermal energy, biofuels, ocean energy and hydropower, nuclear power, as well as advanced energy-harvesting technologies. This chapter will introduce fundamentals and basic design guidelines of advanced energy systems with accompany of materials solutions and environmental compliance of energy materials.

This chapter presents two control methods, MPEC for maximum power extraction of Smart-WEC and MLCT for life cycle extension of tidal energy converter. The results show that MPEC significantly increase power extraction by the Smart-WEC. Also, in order to eliminate speed sensor in the MLCT technique, an artificial neural network is adopted to estimate the tidal speed.

In this chapter, an overview of ocean energy (wave and tidal) converter is presented. The basic concepts and technical challenges hindering the advancement of these technologies are summarized. Smart-WEC, a new type of wave energy converter, with a unique underwater wireless power transfer system is introduced.

Water’s natural flowing movements, such as in rivers and reservoirs, can be used in the production of electricity. Furthermore, both the tidal range (the periodic rise and fall of the sea level) and the energy contained in flow and waves can be used in the ocean energy system. Both types of energy conversion are classed as renewable energies. While the typical use of hydropower has been widespread for hundreds of years, using the ocean for energy is in its infancy. Large hydropower turbine-generator technologies are highly optimized, robust, and cost-effective designs, with peak energy conversion efficiencies of more than 93%. However, advancements for small-scale turbine-generators must reduce technology cost and enable more compact support structures and smaller physical and environmental footprints to achieve economic feasibility. The environmental performance of turbine designs continues to improve, in the form of blade shape enhancements to reduce injury to fish and aeration into turbine flow passages to improve the water quality of releases. Therefore, research and development have been focused on advanced materials and manufacturing for powertrain components, innovative hydrodynamic and mechanical concepts to reduce integrated turbine-generator size (diameter and length) and increase speed, embedded condition monitoring sensors, and powertrain design innovations that afford flexibility in selection of design objectives such as initial cost minimization, efficiency over a range of head and flow rates, and durability or ease of replacement. Ocean energy is one of the most promising resources that can be broadly split into tides, waves, tidal or marine currents, temperature gradients, and Salinity gradients. It has potential of the same order as that of the present capacity of electricity generation worldwide. The majority of ocean energy converters are fabricated from metals like steel and composite materials. Steel offers good fatigue and stress limits, while composites possess some cost and weight saving advantages over steel, but the fatigue and stress limits are not yet well understood in comparison to steel. Other wave devices are being designed to use rubber or other flexible materials as the main structural component. Composites provide many advantages for manufacturing underwater structures such as tidal turbine blades, and wave devices, which generally offer strength, fatigue-resistance, corrosion resistance, buoyancy, and cost-effectiveness. New materials are also explored to meet the needs of a wide variety of designs, many engineering and materials options, and the unpredictable environment of subsea and new ocean energy technologies. Next-generation component would drive the costs down for multiple energy conversion system solutions, including advanced controls to tune devices to extract the maximum energy from each sea state, compact high-torque, low-speed generator technologies, and corrosion- and biofouling-resistant materials and coatings. This chapter will give a brief review about state of the art of advanced materials and devices including various components for hydropower and ocean energy.

High speed rotating machines usually include such components as rotors, bearings, casings, foundations and are widely used in many industries. However their rotors may all face foundation external excitation problems during machine operation and service. Therefore design engineers are interested in accurate rotor response prediction when support structure is subjected to sudden impact excitation in order to set sufficient clearances and ensure machine safe operation. The problem is relevant for marine engines (gas and steam turbines) for evaluation of their reliable operation for the case when a hull of the ship is exposed to impact from giant sea waves. The paper describes methodology for creation of rotor-bearing-support system for HP steam turbine rotor of a transport marine engine whose support structure was subjected to impact excitation. The impact phenomenon was further studied on the base of developed experimental test rig with a simplified rotor structure mounted on foundation with a flexible suspension system. Two numerical models were used for verification of the experimental results: the model with a simplified rotor representation (massless shaft) on a lumped mass foundation structure and a model with beam type rotor on a lumped mass foundation. Proposed numerical models showed adequate results for rotor response prediction, what was confirmed by similarity of obtained curves for impact excitation coefficients and comparability of rotor disk orbits for experiment and simulation. Experimental testing confirmed that external foundation impact excitation may significantly influence on maximum deviations of rotor disk orbits in comparison with the case of rotor normal operation without excitation. Simulation and experiment results revealed that impact excitation coefficients within the tested range of amplitudes and rotor speeds increased almost linear and were proportional to maximum displacement amplitude measured on foundation. For subcritical and supercritical speeds impact excitation coefficients were close in values and increased faster in comparison with excitation performed for the speeds close to rotor critical speed. Proposed method for model creation and analysis could be further used for rotordynamic simulations of more complicated machines e.g. marine power engines.

The search of new energy production forms in order to fulfil the raising energetic demand and diminish the environmental issues derived from the production of energy by using non-renewable resources results in the development of new technologies like the ones related to the offshore marine renewable energy. The interest in the exploitation of this energy source is tangible according to the fact that different projects are going to be developed in the following years, both in Europe and worldwide.

Traditionally, towing tanks had been used primarily to assess the resistance of hulls in calm water, by means of towing geometrically similar scaled models at equal Froude number, usually without appendages such as rudder, propeller, and so on. When wave-making capability is available, towing tanks can also be used to determine seakeeping occurrences, such as green water effects and slamming, for a range of wave frequencies and amplitudes. This is not different for the University Austral of Chile Towing Tank, which has been involved in resistance and seakeeping tests of a variety of hulls, from fishing vessels to ferries, barges, and passenger ships, over the past 40 years. The development of marine industries other than shipbuilding, such as aquaculture, maritime connectivity of isolated geographical regions, and the harvesting of marine energy from tides and waves, have demanded a new set of tests with adequate models to properly replicate the physics of the full-scale case in the towing tank.

Notwithstanding their potential benefit as a non-carbon-emitting energy source, the number and the size of marine renewable energy (MRE) farms increases conflict uses, creating a kind of private occupation of the sea space. The multipurpose marine cadastre (MMC) seems to be an efficient tool to determine a better way to allocate exclusive rights to ocean energy developers, in accordance with other users rights. The United-States are the pioneers with their marinecadastre.gov website, which has been set clearly to promote offshore renewable energy, and many others countries are studying this concept, as a complement to marine spatial planning.

In the past few years, the ocean, as a potential resource of energy, has caught the attention of the industrial sector. However, the possibility of ocean energy exploitation faces several challenges: the development of the needed technologies; the legal framework; the regulatory framework; the environmental aspects. This paper focuses on the international legal framework, specifically with regard to the States’ (exclusive) rights of exploitation within their national jurisdiction and to biodiversity conservation. In this regard, UNCLOS is the primary legal document to be taken into consideration, since it sets a static legal framework of maritime zones and (to them) correlated jurisdiction(al rights). It seems that the exploitation of ocean energy is possible, but two conditions must be satisfied: (1) The States can exploit the ocean energy resource within their national jurisdiction, but it is questionable if they can conserve exclusive rights resulting from industrial activities, due to the fact that rights of third Parties (namely those related to navigation and fishery) must be taken into account; (2) The (sitting and permitting) procedure that allows exploitation of ocean energy will only be legitimized through: (2.1) public participation in the decision making process; (2.2) the implementation of an environmental impact assessment (EIA) regarding all stages of exploitation. This will provide for a long-term monitoring of impacts that exploitation may cause on marine biodiversity, allowing the adoption of adaptive and risk-based management strategies for dealing with uncertainty.

Coastal regions of nations comprising over a billion population contiguous to the Indian Ocean, Bay of Bengal and the Arabian Sea are prone to natural disasters and poor electric supply especially in rural areas and inaccessible regions. Utilization of ocean resources for power generation such as tidal, thermal solar and wind for energy, along with other green technologies like seaweed farming and sustainable fisheries for food would need to be incorporated into a broad framework for the region. Development of ocean-based energy systems can be integrated with early warning networks linked by satellite which can give a few hours to days warning to help mitigate the severity of natural disasters on human life. Some calamities of note have been the Tsunami of 2004, Bangladesh and Orissa floods, earthquakes in Nepal and Pakistan, and recent inundation of Houston and Chennai due to weather and bad flood management. A comprehensive Framework on disaster management was formulated in alignment with the Hyogo Framework (2005–2015). A network of sensors exists in the Indian and Pacific oceans. In addition to the broad objectives of disaster management and cooperation in the Indian Ocean and surrounding regions, the inclusion of the sensor network into the energy grid needs research and development. Some applications and their implementation are looked at, specifically with the difficulties in implementation in the region, and other factors like economic efficiency (rate of returns) in place of mechanical energy efficiency. Ocean energy systems are still in their infancy, while ocean farming technology has been developed and is immediately accessible for further exploitation.

Inspection, repair, and maintenance operations are of crucial importance for the safety and survival of marine renewable energy devices. Current ROV manipulator technology used for subsea operations in offshore oil and gas industry is not adequate for offshore renewables. Target devices for inspection and monitoring operations in oil and gas are close to static, unlike their marine energy counterparts which are in motion due to a highly dynamic environment in which they operate. In this paper we describe motion analysis methods for marine energy devices implemented on the OC3-Hywind floating wind turbine in order to understand the conditions in which inspection and intervention operations are to be performed. Additionally, we present experiments carried out on a laboratory rig which is able to replicate the motion of the OC3-Hywind floating platform, and which will be used in future research on control systems for automated visual inspection and intervention using ROV manipulators.

This chapter presents the results obtained from the analysis of the multi-use design for the Cantabria Offshore site in the Atlantic coast. The analysis shows that the technology exists. Nevertheless at the present the profitability of potential business is still uncertain. The reliability of the activity as a self-sustained business relies on the existence of a stable regulatory framework, on the availability of financial support from the state and on the relaxation of the regulatory barriers existing in the industry. Likewise ocean energy industry is far from been socially accepted in the region. The socio-economic analysis suggests that the multi-use scenario can be profitable.

This book identifies the challenges, solutions, and opportunities offered by smart energy grids (SEGs) with regard to the storage and regulation of diversified energy sources such as photovoltaic, wind, and ocean energy. It provides a detailed analysis of the stability and availability of renewable sources, and assesses relevant socioeconomic structures. The book also presents case studies to maximize readers’ understanding of energy grid management and optimization. Moreover, it offers guidelines on the design, implementation, and maintenance of the (SEG) for island countries.

The objectives of this contribution are to describe and assess the legal obstacles for ocean energy development in Europe. On the one hand, we analyze the impact of the law of the sea, pay special attention to maritime safety issues. On the other, we deal with the EU environmental legislation on nature and biodiversity, together with the cross-cutting strategic tools. And finally, we focus on the obstacles due to the protection of the marine environment.

Some regions of the world concurrently experience a high wave and a high tidal energy resource. These regions include the seas of the northwest European continental shelf, the Gulf of Alaska, New Zealand, northwest Australia, and the Atlantic seaboard of Argentina. Due to the interaction of waves and tides, special consideration needs to be given to resource characterization of marine renewable energy schemes developed in such regions. Waves have been shown to reduce the tidal current, which, because tidal-stream power is proportional to the cube of velocity, reduce the available energy resource. Further, waves can reduce the tidal-stream energy resource during extreme wave periods when ocean renewable devices may not operate. Waves should be also considered in the design and resilience of tidal-stream energy devices. Hence, waves can have a critical effect on the planning, operation, maintenance, and resource assessment of tidal energy sites. Conversely, tides can significantly alter wave properties through various wave-current interaction mechanisms. For example, tidal currents can alter wave steepness which is an important consideration in the design of marine energy mooring. Wave power, in general, is proportional to the wave group velocity and the wave height squared, both of which change in presence of tidal currents. Therefore, resource assessments of such regions should account for the way that one marine energy resource affects another at a variety of timescales from semidiurnal, spring-neap, to seasonal. Finally, wave-current interaction processes affect turbulence, and the dynamics of sediment transport; therefore, they should be considered when the impact of an energy device, or an array of such devices, on the environment is studied. This chapter introduces the basic concepts of wave-tide interaction in relation to the ocean renewable energy resource assessment. Various aspects of the marine renewable energy industry that are affected by wave-tide interactions , such as resource assessment and the influence of wave-tide interactions when characterizing the oceanographic site conditions, are discussed. Methods ranging from simplified analytical techniques to complex fully coupled wave-tide models are explained.

Renewable ocean energy has huge potential to contribute to addressing both climate change and energy security concerns. To realise this potential, it is necessary to have planning and management frameworks that facilitate development of commercial-scale marine renewable energy farms, which harvest offshore wind, wave, and tidal energy. The primary focus of this chapter is ocean energy, namely wave and tidal sources. Currently, consenting and legal processes are often cited as a barrier to efficient and expedient deployment of devices in many locations internationally. This can create high levels of “regulatory risk” which can, in turn, have detrimental consequences for project development timelines and budgets as well as wider negative influence on project investors and financiers. Maritime Spatial Planning (MSP) is a relatively new approach to analysing and allocating parts of marine spaces for specific uses or objectives in order to achieve ecological, economic, and social objectives. MSP does not always result in ocean zoning but instead involves integrated approaches to prioritising uses and activities. As a process, MSP is ecosystem-based, integrated, adaptive, strategic, and participatory—stakeholders are actively engaged in the process. It does not replace single-sector planning or management, but it has a number of advantages that may benefit the development of the renewable ocean energy sector. It can provide greater certainty to the private sector in planning new investments and should reduce conflicts between incompatible users and activities. It should also promote more efficient use of marine resources and space, indicate opportunities for coexistence of activities, and facilitate the implementation of a streamlined permitting process for marine activities. This chapter outlines the planning and management frameworks in place for renewable ocean energy in countries that collaborate through the International Energy Agency’s Ocean Energy Systems Technology Collaboration Programme around the world. A particular emphasis is placed on MSP and how it influences the planning of energy activities currently or how it will influence future ocean energy activity. Implementation of MSP varies from jurisdiction to jurisdiction and can take many different forms. This chapter provides an overview of how the requirements of the ocean energy sector are taken into account when designing marine planning systems, how scientific information is reflected in the process, and the tools used to implement MSP. It also identifies how possible or currently experienced conflicts between different sectors or users are managed. The chapter concludes with a section on the key factors that limit implementation of MSP.

In this chapter it is shown how hydropower plays an extraordinarily important role in the energy future of both Africa and Latin America. Thus, more than 20% of total global hydropower generation occurs in Africa and Latin America combined, and more than 90% of existing renewables in both regions is produced with hydropower. Also, the hydropower capacity in Africa and Latin America is expected to increase over time as several nations are expected to pursue new hydropower development or expansion of existing capacity. Moreover, it is estimated that 92% of the existing total hydropower capacity in Africa is untapped. Conversely, hydropower production in some countries exceeds 85%. Consequently, in many countries energy-intensive industry users can be located as they can consume large quantities of low-cost power produced by hydropower. On the other hand, small hydropower capabilities are likely to become more pervasive over time as environmental concerns, drought and climate change may limit efficiency of larger facilities. In particular, mini-hydro could provide many of the rural electricity. Moreover, climate change may drastically impact the hydropower and consequently, the system’s capability to supply load. Indeed, two lessons can be extracted from recent Brazilian and Venezuelan hydro crisis: the need for diversification from hydropower and the importance of distributed generation. Finally, marine energy plays a very marginal role in renewable electricity production as it has virtually no role in Africa or Latin America. As technology evolves and costs decrease marine energy may play a role in select future locations however it is largely believed that more traditional renewable resources will be adopted much earlier in the energy development cycle.

In the last years, Bayesian optimization (BO) has emerged as a practical tool for high-quality parameter selection in prediction systems. BO methods are useful for optimizing black-box objective functions that either lack an analytical expression, or are very expensive to evaluate. In this paper we show how BO can be used to obtain optimal parameters of a prediction system for a problem of wave energy flux prediction. Specifically, we propose the Bayesian optimization of a hybrid Grouping Genetic Algorithm with an Extreme Learning Machine (GGA-ELM) approach. The system uses data from neighbor stations (usually buoys) in order to predict the wave energy at a goal marine energy facility. The proposed BO methodology has been tested in a real problem involving buoys data in the Western coast of the USA, improving the performance of the GGA-ELM without a BO approach.

International audience; Hybrid power generation systems have become a focal point to meet requirements of electric power demand. This kind of system combines several technologies and is considered as one of the appropriate options for supplying electricity in remote areas, such islands, where the electric utility is not available. It is one of the promising approaches due to its high flexibility, high reliability, higher efficiency, and lower costs for the same produced energy by traditional resources. Typically, hybrid power generation systems combine two or more conventional and renewable power sources. They will also incorporate a storage system. This chapter will focus on a typical hybrid power generation system using available renewables near the Ouessant French Island: wind energy, marine energy (tidal current), and PV. This hybrid system is intended to satisfy the island load demand. It will therefore explore optimal economical design and optimal power management of such kind of hybrid systems using different approaches: (1) Cascaded computation (linear programming approach); (2) Genetic algorithms-based approach; (3) Particle swarm optimization. In terms of economical optimization, different constraints (objective functions) will be explored for a given 25 years of lifetime; such as minimizing the Total Net Present Cost (TNPC), minimizing the Levelized Cost of Energy (LCE). The concept of reliability will also be explored to evaluate the hybrid system based on renewables to satisfy the island load requirements. In this chapter, the Equivalent Loss Factor (ELF) is considered.

The acoustic characteristics of marine energy converters are of interest to those attempting to quantify their environmental effects at larger scale. Such efforts are complicated by the time variation in marine energy converter sound caused by changes in the environmental forcing and converter operation, the difficulty of identifying marine energy converter sound amidst background noise from a range of sources, and the potential masking of marine energy converter sound by non-propagating flow-noise. This chapter discusses each of these challenges and proposes potential solutions to overcome them in a cost-effective manner.

A law adopted in 2015 marked a change in French policy in favour of renewable energy. A number of ministerial decrees and orders were issued starting in early 2016 introducing significant changes to the financial support of renewable electricity. In various sectors and for several years France has launched tender procedures as a means to fix the guaranteed purchase price when feed-in tariffs apply (e.g. photovoltaic, offshore wind, wood). Beyond certain capacity floors, the country is now applying the principle of direct selling on the market with additional compensation. The promotion of heat from renewable sources has undergone fewer changes since the previous regulatory framework proved to be quite effective, especially for wood and heat pumps. Only the biofuel sector faces uncertain future demand. France holds great potential for many renewable sources; alongside the most common sectors (biomass, hydro, wind, photovoltaics) the country can also develop less widespread sources, ocean energy or high-temperature geothermal energy, for example. France is also striving to stimulate research and innovation in this area.

The gradually growing demands of energy and global warming are series problems the globe facing. Facing this condition, renewable and green energy sources may play a key role in both of meeting the growing demand for energy and preventing global warming. Among the novel renewable and green energy sources, wave energy is one of the most promising marine energy sources. However, utility of wave energy resource might cause environment evolutions, which has to be paid much attention. So we can balance environment and resources. The present work focuses on the evolution of wave climate and wave-induced longshore current. To demonstrate effects of wave farm on evolution of the two parameters mentioned above more clearly, Zhangjiapu (ZJP) nearshore areas are regarded as the potential wave farm location. There are large wetland areas having sensitive environment problems. Therefore, this chapter studied the evolution of nearshore hydrodynamic environment in ZJP nearshore areas, including wave climate and wave-induced longshore current, which was caused by the installation of wave farm. Numerical simulation has been adopted to investigate the effects induced by wave farm on nearshore hydrodynamic environment. The wave and wave-induced longshore current have been simulated by flow model Delft3D. The significant wave height and period gotten by numerical model agree with measured data generally. There are obvious changes occurring when wave farm is installed along 20-m-depth contour in ZJP. This chapter is structured as the following five parts: First, theories of wave modelling and methods of wave energy resources assessment and hydrodynamic environment are introduced. Second, the model setting and validation are discussed. Third, wave energy resources were investigated based on wave parameters outputted by wave numerical modelling. Fourth, evolution of wave climate and longshore current induced by the potential wave farm is analysed by hydrodynamic modelling. Finally, some summaries about the evolution of hydrodynamic environment when wave farm is set up are given.

Harvesting water wave energy is a great challenge to traditional electromagnetic generator (EMG) mainly due to its low frequency, large area of distribution, random in amplitude and high cost. This chapter presents how TENG can be an effective technology for harvesting water wave energy by using triboelectric effect and electrostatic induction effect. The high output voltage of TENG makes the harvested energy being effectively useful. A network design is also presented for harvesting ocean energy in general toward the dream of blue energy. The high performance of TENG at low frequency is an unreplaceable and unbeatable advantage in comparison to EMG, making the two technologies complement each other for different applications.

This chapter describes a general methodology in order to calculate the costs of a floating offshore wind farm. It is based on the analysis of its life-cycle cost system (LCS). In this sense, several phases have been defined: conception and definition, design and development, manufacturing, installation, exploitation and dismantling. The calculation of costs of each of these steps gives the total cost of a floating offshore wind farm. The method proposed has been applied to the particular case of the Galician coast, where a floating offshore wind farm could be installed due to the great offshore wind potential and the depth of its waters. Results indicate that the most important cost in the life cycle of a floating offshore wind farm is the manufacturing cost. It is due to the fact that the floating offshore wind platforms and the offshore wind turbines have a high cost. The methodology proposed can be used by investors in the future to know the real costs of a floating offshore wind farm.

Offshore wind power has been in recent years a highly debated topic and subject to investigation by the several players in the renewable energy sector. The advantages of this form of renewable energy are well known being some of the most important aspects the large wind resource and available area for wind farms’ installation. Nevertheless, the planning of an offshore wind energy project needs to be addressed carefully so as not to interfere with other economic activities or sensitive environmentally protected areas, among other constraints. Similarly, although the offshore wind resource is naturally higher than the resource onshore, the investment costs (including operation and maintenance) are also considerably higher, hence the need to establish straightforward and transparent methodologies for offshore wind planning. Most of the methodologies used for planning purposes are based on geographic information systems (GIS) due to its powerful capabilities in managing, formatting and modelling large amounts of georeferenced data usually involved in planning procedures. This chapter presents a methodology for offshore wind energy planning taking into consideration the several aspects of sea use and the main restrictions which can be relevant for wind farm installation. The methodology consists on the use of a GIS to manage the required information (resource and restrictions maps) and to develop a set of tools that enable the user to add, modify and model the information according to his objectives.

In order to solve the energy problem of the underwater mooring platforms, a horizontal pendulum-type ocean rocking energy conversion system scheme is proposed. Based on the multi-body dynamics software LMS, the motion characteristic simulation model is established, and the influence parameter on motion characteristic is analyzed, such as pendulum mass, pendulum length, excitation frequency and amplitude, and system damping coefficient. The simulation results show that output power is increasing with the pendulum mass, pendulum length, excitation frequency, and excitation amplitude, which has a practical guiding significance to the design of the mode of the current power generation system.