Marine Energy Development Research Articles

Preface for Special Issue on “Key Mechanical Problems of Marine Energy Development Equipment”

Preface for Special Issue on “Key Mechanical Problems of Marine Energy Development Equipment”

A comparative study of laws and policies on supporting marine energy development in China and Korea

Marine energy technologies in China and Korea are still in the follow-up stage compared to advanced countries. However, both countries have abundant marine energy resources, and the research for early commercialization in development, advancement, and verification of marine energy technology is actively underway. However, for early commercialization of marine energy, national policy support, investment, and development strategies are required. In this study, the current technologies, laws, policies and incentive systems in China were compared to those in Korea, and challenges to be solved were reviewed. As a result, it was found that concrete strategies to support marine energy need to be established, and the subsidy system to induce private company participation should be improved. In addition, since recognizing the necessity of marine energy development, both countries are expected to play an important role in the global marine energy market in the future.

A Summary of Environmental Monitoring Recommendations for Marine Energy Development That Considers Life Cycle Sustainability

Recommendations derived from papers documenting the Triton Field Trials (TFiT) study of marine energy environmental monitoring technology and methods under the Triton Initiative (Triton), as reported in this Special Issue, are summarized here. Additionally, a brief synopsis describes how to apply the TFiT recommendations to establish an environmental monitoring campaign, and provides an overview describing the importance of identifying the optimal time to perform such campaigns. The approaches for tracking and measuring the effectiveness of recommendations produced from large environmental monitoring campaigns among the stakeholder community are discussed. The discussion extends beyond the initial scope of TFiT to encourage discussion regarding marine energy sustainability that includes life cycle assessment and other life cycle sustainability methodologies. The goal is to inspire stakeholder collaboration across topics associated with the marine energy industry, including diversity and inclusion, energy equity, and how Triton’s work connects within the context of the three pillars of energy sustainability: environment, economy, and society.

A Framework for Effective Science Communication and Outreach Strategies and Dissemination of Research Findings for Marine Energy Projects

Marine energy is an emerging renewable energy industry with the potential to produce 2300 terawatt-hours per year from resources within the United States. As development and testing of marine energy devices advance, regulatory and permitting decision-makers are concerned about the uncertainty surrounding the potential environmental effects resulting from the introduction of these novel devices in coastal and riverine environments. The Triton Initiative researches and provides recommendations for environmental monitoring technologies and methods to inform industry stakeholders with the data necessary to permit the testing of marine energy systems. Effective dissemination of the research findings is essential for improving the accessibility of data to stakeholders who may use the results to inform policy decisions, yet few frameworks for conducting science communications for marine energy projects exist. In this paper, we present tools, channels, and tactics for developing a science communication framework for marine energy projects, or similar areas of study, using the Triton Initiative’s pilot science communication program as a case study. By leveraging existing bodies of work in disciplines such as communications theory, marketing, public relations, and social science, the presented framework includes audience identification and analysis; channel development, including a website, blog, newsletter, social media, and webinars and presentations; and metrics for determining success. Outcomes from one year of Triton’s case study are presented, including the most effective tactics and lessons learned.

What’s in My Toolkit? A Review of Technologies for Assessing Changes in Habitats Caused by Marine Energy Development

Marine energy devices are installed in highly dynamic environments and have the potential to affect the benthic and pelagic habitats around them. Regulatory bodies often require baseline characterization and/or post-installation monitoring to determine whether changes in these habitats are being observed. However, a great diversity of technologies is available for surveying and sampling marine habitats, and selecting the most suitable instrument to identify and measure changes in habitats at marine energy sites can become a daunting task. We conducted a thorough review of journal articles, survey reports, and grey literature to extract information about the technologies used, the data collection and processing methods, and the performance and effectiveness of these instruments. We examined documents related to marine energy development, offshore wind farms, oil and gas offshore sites, and other marine industries around the world over the last 20 years. A total of 120 different technologies were identified across six main habitat categories: seafloor, sediment, infauna, epifauna, pelagic, and biofouling. The technologies were organized into 12 broad technology classes: acoustic, corer, dredge, grab, hook and line, net and trawl, plate, remote sensing, scrape samples, trap, visual, and others. Visual was the most common and the most diverse technology class, with applications across all six habitat categories. Technologies and sampling methods that are designed for working efficiently in energetic environments have greater success at marine energy sites. In addition, sampling designs and statistical analyses should be carefully thought through to identify differences in faunal assemblages and spatiotemporal changes in habitats.

Biological Consequences of Marine Energy Development on Marine Animals

Marine energy devices harness power from attributes of ocean water to form a sustainable energy source. Knowledge gaps remain about whether marine energy systems can affect the environment, adding another threat to animal populations and habitats already under pressure from climate change and anthropogenic activities. To date, potential environmental effects have been studied under the scope of stressor–receptor interactions, where moving parts of, or emissions from, a system could harm the animals, habitats, and natural processes. While crucial for understanding effects and identifying knowledge gaps, this approach misses a holistic view of what animals may experience in the presence of marine energy systems. We look at six biological consequences and forces that drive the health of an animal population and the effects expected from marine energy development: success of early life stages; changes in competitive capabilities; growth and survival based on food availability; susceptibility to predators; injury or death; and reproductive success. We use case studies to develop this approach, focusing on a variety of marine animals. An approximate level of risk is assigned for each interaction based on the biological consequences. This work highlights the need to examine the effects of marine energy development on animal populations within their natural habitats.

A bibliometric review on the implications of renewable offshore marine energy development on marine species

The growing global demand for sustainable and environmentally friendly energy has stimulated the rapid adoption of renewable offshore energy. However, infrastructure needed for green energy production ironically impacts upon marine species and biodiversity. Consequently, this positional review paper seeks to comprehensively synthesise the prevailing body of knowledge on the impact of offshore energy development on a broad range of marine species. An interpretivist philosophical stance and inductive reasoning was adopted using scientometric analysis to conduct a rich synthesis of extant literature. From an operational perspective, the Scopus database was utilised to search for key terms on the phenomena under investigation and using the VoS Viewer software for the identification of trends using scientometric maps. The analysis reveals that research in this area of science has increased significantly over the last decade but private sector involvement is conspicuous by its absence. Primary concerns among the research community include the impact of energy development on the abundance of species, pollution and biodiversity behaviour and migration. At present, researchers have extensively focused on the impact of offshore wind farms on fish and marine mammals. However, the literature reveals no significant long-term impact upon energy development on most marine species albeit, short-term interference has raised concerns (from sound, disruption of navigation and foraging patterns, and damage of habitat). To minimise short term disruption, researchers have recommended the use of acoustic deterrence during construction, enforcement of protected areas and continued research.

Energy System Sustainability

This issue presents some of the latest findings within energy planning research and form a special issue from the 2021 5th Annual Conference of the Portuguese Association of Energy Economics as well as for the 2020 Sustainable Development of Energy, Waste and Environmental Systems conference series. The work presented probes into the effects of the European emissions’ trading system on innovation, and the development of the Chinese wind power industry. Notable is also an analysis of people at Portuguese universities revealing lesser knowledge of renewable energy technologies but a more positive attitude towards this among women – and vice versa among men. EnergyPLAN-based energy systems analyses with cases from Iran and Serbia are presented, and different indicators for energy systems analyses are deliberated in a Mexican context. Marine energy developments in Columbia, the United Kingdom, Canada and Denmark are discussed with a focus on siting and barriers. Also, barriers against solar energy exploitation in Indonesia are explored as are barriers against energy savings in Nigeria.

Research on the Blade Motion of a Bidirectional Energy-Generating Turbine under Integrated Wave and Tidal Current Action

An integrated wave-tidal current power turbine is affected by both wave and tidal current forces, and its energy efficiency is closely related to the velocity and direction of the two forces. To improve the probability of the horizontal axis turbine reaching maximum energy efficiency under real-time changing sea conditions, we performed the following investigations in this study. Based on the actual application scenario of Lianyungang port, a time series prediction model of tidal current (velocity and flow direction) and wave (mean wave direction, mean wave period, and significant wave height) data for the past year was established. The changes in waves and tidal currents within 24 h after the cutoff point of the existing data were predicted. The integrated wave-tidal current mechanism was studied, and the superposition of wave energy and tidal current energy was transformed into the equivalent velocity vector of wave-tidal current integration. The conversion coefficient between waves and equivalent flows was determined by a numerical wave flume simulation. According to the historical wave and tidal current data, the equivalent velocity range of the integrated action of waves and tidal currents in Lianyungang was determined. The influence of different blade motions on the energy harvesting efficiency of the turbine under the corresponding flow conditions was studied using the Computational Fluid Dynamics (CFD) method to determine the blade motion law of the turbine. The blade motion law of the prototype was verified in a sea trial experiment. The experimental results were basically consistent with the simulation results for the blade motion law designed according to the wave and tidal current prediction law. This design scheme can provide a reference for engineering design for the development and utilization of new marine energy.

The contribution of ocean-based solutions to carbon reduction in China

Climate change has become a great challenge for humanity. However, the current climate change mitigation measures, primarily concentrate on land, more or less neglecting the vital role of the ocean-based solutions. While the ocean is a crucial regulator of the global climate, ocean-based solutions could also play an essential role in climate change mitigation and policymaking. This paper developed an Ocean-based Solutions Carbon Reduction Assessment Model (OSCRAM) that addresses coastal ecosystems, ocean energy, marine transportation, fishery, and seabed to estimate the oceanic contribution to climate change mitigation. It has been applied to evaluate the capacity of carbon emission reduction through oceans in China. We found that the total contribution for carbon emission reduction was about 6.86 Tg CO2 per year, and it may reach 139.39 Tg in 2030 under the target scenario. The results indicated that the ocean has huge potential to reduce carbon emissions. The development of marine energy and low-carbon marine shipping may have more potential for emission reduction in China, and the government should also protect and restore coastal wetlands for their enormous carbon storage. It can also provide a reference for the globe and other nations in achieving emission reduction goals.

Numerical Simulation of Fluid Carrying Pollutant Particles Erosion in Elbow Pipe Is Carried out by COMSOL

With the development of Marine energy to the deep and ultra-deep-water field, the severe environment of high temperature and high pressure in the engineering background makes the problem of flow security in oil and gas transportation system more serious and prominent. For this part of the underwater production and processing system, more stringent requirements are put forward. In order to study the erosion of fluid pipelines such as oil and natural gas, the COMSOL (A large-scale advanced numerical simulation software) finite element model was used. Under the condition of different flow parameters, the erosion trajectory of solid particles in the pipeline and the erosion failure rule of the bend are obtained. In this paper, the erosion wear rate of 90° pipe elbow is calculated, and three different erosion models are compared.

Research on Coupled Model of the Marine Energy-Economic-Environment System

Lin, X. and Chen, C., 2020. Research on coupled model of the marine energy-economic-environment system. In: Gong, D.; Zhang, M., and Liu, R. (eds.), Advances in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 106, pp. 89–92. Coconut Creek (Florida), ISSN 0749-0208.With the implementation of the marine strategy in China and around the world, the development and utilization of the world's oceans have been greatly increased. However, there are contradictions and pressures between exploitation of resources and protection of the environment in the development of the marine economy. Based on the coupling among marine resources, environment, and economy, this paper constructs an evaluation index system for coupling utilization of marine resources, protection of the environment, and development of the marine economy and explores the coupling and coordination relationships among the three. In the structure of the marine energy-economic-environment system, if the economic subsystem develops too fast, it will cause the a loss of energy and damage to the ecological environment. Based on the perspective of coupled development, the study of the degree of coordination within the marine energy-economic-environment system is conducive to the development and utilization of marine energy while protecting the marine environment and promoting the scientific, reasonable, and healthy development of the marine economy. This paper first introduces research into the marine energy-economic-environment system and then constructs a coupled model of the marine energy-economic-environment system based on big data, which can mine the value behind the data quickly, accurately, and effectively by using big data technology.

Industrial Economic Benefit Analysis of Marine New Energy Development under Low Carbon Economy Background

Hou, P. and Xu, M., 2020. Industrial economic benefit analysis of marine new energy development under low carbon economy background. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 1014–1017. Coconut Creek (Florida), ISSN 0749-0208.The traditional analysis method of industrial and economic benefits of marine new energy development is low in accuracy, so a low-carbon economic analysis method of marine new energy development is designed. The basic balance between input and output of new marine energy development industry is analyzed, and the line balance relationship and column balance relationship of industrial economic benefits are calculated to reflect the consumption coefficient and use relationship among industries. In this work, the static analysis method is adopted to analyze the net present value and the rate of return of profitability, and to evaluate the industrial and economic benefits.

Public perceptions of tidal energy: Can you predict social acceptability across coastal communities in England?

Early consideration of potential societal issues faced by the nascent tidal industry is important to facilitate public engagement and potentially avoid levels of conflict that have arisen within other renewable energy sectors; general expressions of public support (as reported in national-scale attitude surveys) do not always translate into approval for local developments. It is a very appealing idea that the likely response of different types of communities to marine energy developments can be mapped and used to support planning. This study examined the attitudes of 963 people in South West England to hypothetical local tidal energy projects, analysing the results both by geographic location and according to the coastal community typology developed for England by the Marine Management Organisation. With the exception of age, demographic variables had little influence on the level of opposition to tidal energy, which instead was affected more by factors such as attitudes towards tidal energy in general (in particular its likely environmental impact), activities undertaken at the coast, and place attachment. These significant factors are typically not captured by the national census data used to determine community types. Any predictions about the acceptability of energy projects made as a result of community mapping based on demographic variables will not be a substitute for thorough public engagement and consultation, which should centre on the implications of tidal developments for the environment.

Resonant frequencies analysis and vibration control of fluid in three-dimensional (3D) moonpool: Analytical modeling and experimental study

Moonpool widely exists in the fields of offshore oil and gas resources drilling, marine energy development and so on, and also has important applications in special ships and surface ships. The aim of this paper is to present an accurate three-dimensional modeling method and analyze resonant frequencies of fluid in three-dimensional moonpool. Based on the three-dimensional potential flow theory, the governing equations and boundary conditions of the fluid in the three-dimensional moonpool are established. According to the characteristics of the governing equations and boundary conditions of the fluid in the moonpool, the velocity potential of the fluid in the moonpool is expanded into the form of the sum of three-dimensional Fourier series and smooth auxiliary functions. Then, the velocity function is introduced into the governing equations and boundary conditions, so that the complex partial differential equations can be transformed into a set of simple linear equations, and the resonance frequency of the fluid vibration in the moonpool can be obtained by solving the linear equations. In order to verify the validity of the three-dimensional accurate model proposed in this paper, numerical examples and experimental verification are carried out, and then the numerical and experimental results show that the proposed solution has good convergence accuracy and calculation accuracy. On this basis, the effects of the length, width and water depth of the moonpool on the resonant frequencies and modes are discussed, and the natural vibration behavior control of the fluid in the three-dimensional moonpool are analyzed in detail. In this work, the three-dimensional analytical solution is proposed for the first time to study the natural vibration characteristics of the fluid in the three-dimensional moonpool, and its correctness is verified by the model experiment. At the same time, some bright research results are also given, which is of great engineering significance for understanding the resonant frequencies and modes of the fluid in the complex moonpool structure.

Marine Heat as a Renewable Energy Source

The ocean, which covers two-thirds of the land surface, receives heat from the sun's rays. Ocean water also receives heat that comes from geothermal heat, which is magma located under the seafloor. Ocean surface temperatures are warmest near the equator, with temperatures from 25°C to 33°C between 0 degrees and 20 degrees north and south latitude. This temperature difference can be utilized to run the driving machine based on the thermodynamic principle. A technology called Ocean Thermal Energy Conversion (OTEC) is capable of converting the temperature difference into electrical energy. OTEC is a power plant by utilizing the difference in the temperature of seawater on the surface and the temperature of deep seawater. This paper briefly overviews of how ocean heat can be utilized as a renewable energy source to produce electrical energy. The development and exploitation of renewable marine energy in the future are feasible and this will involve multidisciplinary fields such as robotics and informatics.

Review on marine energy program

As our fossil fuel is rapidly depleting, Indonesia need to explore new source of energy to support our economic development. One of this possibility come from the sea where the potential is estimated to reach 49 GW and only very small portion has been utilized. This paper describes activities related to marine energy development particularly in some selected Asian countries and the Pacific. Marine energy development described here is limited to power generation using sub-surface current and OTEC (Ocean Thermal Energy Conversation). It was the Tokyo Electric Company who started to build 100 kW OTEC on the island of Nauru in 1970, and it was the first system operating on grid. Marine energy studies, particularly on OTEC was first conducted by the IOES (Institute of Ocean Energy, Saga university). For the case of sub surface sea current research in Indonesia was first conducted by T-Files in which they constructed a 5 kW power generation and tested in Nusa Penda, Bali. Later in 2010 a 10 kW sub-surface sea current was also constructed and tested in Larantuka, Flores island. Although marine energy has been considered high cost several simulation studies in Indonesia have indicated that the cost of electricity production using OTEC could be reduced to below US$07/kWh.

Research On Wave Energy Generation Technology

With the increasingly serious environmental pollution and the intensified energy war, the all-round development and utilization of marine energy will become an indispensable key link in China’s implementation of the maritime power strategy. In recent years, with the support of the state, China’s wave energy generation technology has made a key breakthrough.In order to protect the environment, save energy and reduce emissions, and promote the utilization of wave energy, this paper reviews the development history of application generation technology, summarizes its development from two aspects of optimization and application of wave energy conversion devices, and analyses the application examples of wave energy generation devices on ships. This paper summarizes the application trend of wave power generation devices on ships: wave power generation should be used as auxiliary and domestic electricity for ships and wave energy should be combined with other new energy sources. Wave energy application in marine power generation can effectively reduce emissions from ships, which is conducive to the sustainable development of human society.

Growing Professionals in Science and Technology of Korea’s New Marine Industry Sector

With consideration to research nature, scope of available materials and industrial feature, we investigate cultivation of professionals in the three new marine industries such as marine energy, marine bio-industry and submarine hydrothermal deposits development. More specific, we investigate trends of marine science and technology manpower at the national level in Korea nurturing policy to forecast mid and long term expert manpower demand and to respond to trends and forecasts of major fields. Cultivation of necessary professionals is an essential prerequisite for growth of new marine industry and its contribution to national economy. Because the new marine industry was recently introduced, the established system and policies for professionals in science and technology did not reflect demand for this new industry, which requires improvement. Since new marine industry is a new field, it is difficult for customized talent to be supplied directly from existing manpower training system. Therefore, it is necessary to cultivate talented people with fused thinking and ability. In the existing system, it is necessary to strengthen efforts to develop professional manpower with fusion competence, and it is also necessary to make policy efforts to build a new system such as cooperation process.

Empirical determination of severe trauma in seals from collisions with tidal turbine blades

Abstract Tidal energy converters (turbines) are being developed in many countries as part of attempts to reduce reliance on hydrocarbon fuels. However, the moving blades of tidal turbines pose potential collision risks for marine animals. Accurate assessment of mortality risk as a result of collisions is essential for risk management during planning and consenting processes for marine energy developments. In the absence of information on the physical consequences of such collisions, predicting likely risks relies on theoretical collision risk models. The application of these at a population level usually assumes that all collisions result in mortality. This is unlikely and the approach therefore produces upwardly biased estimates of population consequences. In this study, we estimate the pathological consequences of direct collisions with tidal turbines using seal carcasses and physical models of tidal turbine blades. We quantify severe trauma at a range of impact speeds and to different areas of seal carcasses. A dose–response model was developed with associated uncertainty to determine an impact speed threshold of severe trauma to use in future collision risk models. Results showed that severe trauma was restricted to the thoracic region, with no evidence of injury to the lumbar or cervical spine. Pathological indicators of mortality were only predicted to occur in collision speeds in excess of 5.1 m/s (95% C.I. 3.2–6.6) and was affected by body condition; increasing blubber depth reduced the likelihood of severe trauma. Synthesis and applications. This study provides important information for policy makers and regulators looking to predict the potential impacts of tidal turbines on marine mammals. We demonstrate that the probability of severe trauma in seals due to collisions with turbine blades is highly dependent upon collision speed, and that the majority of predicted collisions are unlikely to cause fatal skeletal trauma. We recommend that collision risk models incorporate appropriate mortality assumptions to ensure accurate estimates of the population consequences are produced in risk assessments for tidal turbine deployments.