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The limited supply of fossil fuels, constant rise in the demand of energy and the importance of reducing greenhouse emissions have brought the adoption of renewable energy sources for generation of electrical power. One of these sources that has the potential to supply the world’s energy needs is the ocean. Currently, ocean in West African region is mostly utilized for the extraction of oil and gas from the continental shelf. However, this resource is depleting, and the adaptation of ocean energy could be of major importance. The purpose of this paper is to discuss the possibilities of ocean-based renewable energy (OBRE) and analyze the economic impact of adapting an ocean energy using a thermal gradient (OTEC) approach for energy generation.

The analysis is conducted from the perspective of cost, energy security and environmental protection.

This study shows that adapting ocean energy in the West Africa region can significantly produce the energy needed to match the rising energy demands for sustainable development of Nigeria. Although the transition toward using OBRE will incur high capital cost at the initial stage, eventually, it will lead to a cost-effective generation, transmission, environmental improvement and stable energy supply to match demand when compared with the conventional mode of generation in West Africa.

This study will be helpful in determining the feasibility, performance, issues and environmental effects related to the generation and transmission of OBRE in the West Africa region.

The study will contribute toward analysis of the opportunities for adopting renewable energy sources and increasing energy sustainability for the West Africa coast regions.

Localization is one of the critical issues in Ocean Internet of Things (OITs). The existing research results of localization in OITs are very limited. It poses many challenges due to the difficulty of deploy beacon accurately, the difficulty of transmission distance estimation in harsh ocean environment and the underwater node mobility. This paper aims to provide a novel localization algorithm to solve these problems.

This paper takes the ship with accurate position as a beacon, analyzes the relationship between underwater energy attenuation and node distance and takes them into OITs localization algorithm design. Then, it studies the movement regulation of underwater nodes in the action of ocean current, and designs an Energy-aware Localization Algorithm (ELA) for OITs.

Proposing an ELA. ELA takes the ship with accurate position information as a beacon to solve the problem of beacon deployment. ELA does not need to calculate the information transmission distance which solves the problem of distance estimation. It takes underwater node movement regulation into computation to solve the problem of node mobility.

This paper provides an ELA based on the relationship between propagation energy attenuation and node distance for OITs. It solves the problem of localization in dynamic underwater networks.

This paper aims to conduct a comprehensive literature review in the tidal energy physics, the ocean environment, hydrodynamics of horizontal axis tidal turbines and bio-mimicry.

The paper provides an insight of the tidal turbine blade design and need for renewable energy sources to generate electricity through clean energy sources and less CO₂ emission. The ocean environment, along with hydrodynamic design principles of a horizontal axis tidal turbine blade, is described, including theoretical maximum efficiency, blade element momentum theory and non-dimensional forces acting on tidal turbine blades.

This review gives an overview of fish locomotion identifying the attributes of the swimming like lift-based thrust propulsion, the locomotion driving factors: dorsal fins, caudal fins in propulsion, which enable the fish to be efficient even at low tidal velocities.

Finally, after understanding the phenomenon of caudal fin propulsion and its relationship with tidal turbine blade hydrodynamics, this review focuses on the implications of bio-mimicking a curved caudal fin to design an efficient horizontal axis tidal turbine.

Since 2000, China, along with the USA, UK, France, Japan and many other developed countries have drawn up new blueprints for the development of a marine economy. At present, international marine economics research has entered into a new period of development, and the research methods of ocean econometrics are becoming more complex and mature. The purpose of this paper is to review the progress of international marine econometrics research and gives the development direction of marine econometrics.

The Web of Science core collection database was utilized, harvesting data from 1996 to May 2018, measuring the marine economy research from 1,489 articles as its sample, using CiteSpace visualization analysis tools.

Mapping the knowledge map from annual international marine economic metrology, literature identification, keywords, involving disciplines and related journals, countries (regions) and research and analyzing the research status of reveals the research frontiers of international marine economy measurement (learning) by using CiteSpace.

The conceptions and characteristics of marine econometrics are defined and analyzed, and the theoretical method of marine econometrics is sorted out. Mapping the knowledge diagram of marine econometrics and discussing the research status of international marine economics, and clarifying the existing problems, future opportunities and challenges of international marine econometrics research.

The purpose of this paper is to disseminate the lessons learned from the successful deployment of a wave energy converter (WEC) and accelerate growth in the field of ocean energy.

A thorough, well structured, documented, industrial approach was taken to the deployment because of the depth and scale of the task required. This approach is shown throughout the paper, which reflects the importance of a comprehensive project plan in success as well as failure.

The findings demonstrate the viability of the use of off shore WEC to generate electricity and that such a project can be completed on time and on budget.

The research implications of the paper include the importance of an enhanced, integrated supervisory system control in terms of efficiency, operation and maintenance, and long-term viability of WECs. This paper can be used to help guide the direction of further research in similar areas.

The practical implications include proof that WEC deployments can be carried out both on time and under budget. It highlights much of the practical data collected throughout the course of the project and presents it so that it might be used as a guide for future projects.

At the time of this paper, successful deployment of off shore WECs has been a rare accomplishment. Because the project was publicly funded, the data collected during this project, both technical and practical, is freely available.

The purpose of this study is to provide a foundational understanding of the internationalization of small- and medium-sized enterprises (SMEs) operating in the context of renewable energy markets. The focus is on exploring and identifying the managerial-, firm- and environmental-level antecedents to their international expansion, which also furthers the understanding of the distinct SME’s internationalization context within the renewable energy market.

The study adopts a qualitative multiple case study approach in a Finnish SME context and identifies the antecedents’ relative prominence at the managerial, firm and environmental levels.

The findings indicate that, although internationalization antecedents of renewable energy SMEs differ owing to market forces such as trends, networks and changing regulatory policies, they share antecedents similar to those of SMEs in other industries.

The main limitation of this study is its single-country home market empirical context. Future studies should expand analysis to different regulatory and regional environments.

To the authors’ knowledge, there are few studies that explore the antecedents of SMEs’ internationalization, especially in the renewable energy market context. Hence, this study contributes to the international business and entrepreneurship literature by illustrating the fundamental managerial-, firm- and environmental-level antecedents to the internationalization of SMEs operating in the renewable energy business. In addition, it highlights the peculiarities of renewable energy SMEs’ internationalization, suggesting that extant research on SMEs’ internationalization has not adequately captured the intricacies present in the internationalization of renewable energy enterprises.

Because of the shortage of energy, the development of green and reliable energy is particularly important. As a green and clean energy, wind power is widely used. As the core component of wind power generation, it is particularly important to choose generators with high reliability. Switched reluctance machine is widely used as generators because of its strong fault tolerance and high reliability. Therefore, this paper aims to propose a power converter and its control strategy to improve the efficiency of switched reluctance generators.

In this paper, a full-bridge power converter (FBPC) instead of the asymmetric half-bridge power converter (AHBPC) is adopted to drive the switched reluctance generator (SRG) system. Compare the FBPC with the AHBPC, the FBPC has several advantages including low cost and modularization, and operation process of SRG winding current direction is variable.

The results show that the SRG system can keep smooth operation by the FBPC with relatively high efficiency.

The FBPC is suitable to drive the SRG system. Meanwhile, this paper introduces two excitation modes of the FBPC as three-phase three-beat mode and six-phase six-beat mode. When the six-phase six-beat control strategy is adopted, the dead band time of the converter can be avoided. At the same time, the SRG has higher efficiency.

The purpose of this paper is to find some feasible measures to solve the problems faced in China's renewable energy development and promote the industrial development of China's renewable energy.

The paper summarises the status and studies the problems of China's renewable energy industrial development, and then puts forward some proposals for the industrial development.

The paper finds that most of China's renewable energy technology is still in the transitional period from research and development to industrial production, and that the renewable energy industrial development needs the establishment of a series of technical experiments and demonstration projects to analyze and investigate the resources, the conversion and market development experience, and then form complete sets of equipment design and manufacturing, cultivation and collection of biomass resources and technology development capabilities, and that regulations should be established to provide a solid foundation for the large‐scale development of China's renewable energy. As a result, some development measures are suggested in the paper.

The paper raises the problems faced in China's renewable energy development, and gives some feasible development measures for the industrial development of China's renewable energy.

The purpose of this paper is to describe the design and function of Fred. Olsen's wave energy converter (WEC) system Lifesaver with special focus on the stand-alone electrical system that is implemented for operation without grid-connection.

The paper focus on the detailed design of the DC-Link system that drives the industrial 400 VAC inverters and generators for the production system. The DC-Link is stabilized by an ultra capacitor bank and has no external source or grid-connection.

The system has been tested through extensive sea trials since April 2012 and has proved its function. Some results from real sea testing are presented.

This paper proves the viability of the specified design and may serve as a basis for the design if similar systems in the future.

This paper presents a WEC system that has proven successful operation through practical tests, and is therefore regarded as a high-value paper as there is limited experience on this subject.