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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.

The purpose of this paper is to design, investigate and optimize a horizontal axis tidal turbine (HATT) using computer-aided numerical simulation and computational fluid dynamics (CFD). This is the first step of research and development (R&D) for implementation in the Persian Gulf condition. To do so, suitable locations are reviewed. Then, the optimization is focused on determining the optimum fixed pitch angle (β) of a three-bladed HATT based on the widespread multiple reference frame (MRF) technique to calculate power and thrust coefficients at different operational rotating speeds.

To simplify the problem and reducing the computational costs due to cyclic symmetry only one blade, accordingly one-third of the whole computational domain is considered in the modeling. Due to flow’s nature involving rotating, separation and recirculation, a realizable κ-ε turbulence model with standard wall function is selected to capture flow characteristics influenced by the rotor and near the wall region. Simulations are conducted for two free-stream velocities, then compared with their dependencies through the dimensionless tip speed ratio (TSR) parameter.

The validation process of the simulations is carried out by the use of AeroDyn BEM code, which has been evaluated by comparing with two experimental data. As results, the highest coefficient of power is achieved at ß = 19.3° at TSR = 4 with the value around 0.41 and 0.816 for thrust coefficient. Furthermore, to comprehend the rotor’s performance and simulation method, flow characteristics due to the rise in angular velocity is discussed in detail. Moreover, the major phenomenon, cavitation occurrence, is also checked at the critical situation where it is found to be safe.

By comparing and evaluating the results to other HATTs, it implies that the proposed rotor of this study is feasible and proved by CFD evaluation at this step. However, the current rotor is awaiting a justification through experimental assessment.

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.

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.

In this paper we assess whether the balanced scorecard (BSC) supports the necessary functions for organizational viability. To this purpose, we use the viable system model (VSM) as a means to describe the functions required for organizational viability. Then we use the VSM as a template to assess whether and how the BSC supports these functions for organizational viability.

Alec Snobel suggests that our conservation programme may be too negative and calls for more emphasis on the development of alternative power sources.

The world is increasingly complex and the most serious challenges are global in nature. Questions to do with sustainable and equitable development, democratic change, terrorism and transnational crime, for instance, require collaborative action among governments, international organizations, corporations, universities, and nongovernmental organizations. This article, which describes 15 global challenges compiled as part of the Millennium Project’s 2002 State of the Future report, assesses the global and local prospects for humanity.

The Pacific Island countries are culturally diverse, politically challenging, extremely vulnerable to climate change and natural disaster impacts, and financially heavily dependent on aid flows. This chapter examines barriers and opportunities for Green growth (GG) to flourish in a country with a practically non-existent real economy and which is currently under the threat of disappearance under water. It draws on a visiting experience and lessons from the literature and tries to investigate the role of innovation and entrepreneurship as poles of re-birth and local creativity. More particularly, I here discuss why a least developed country such as Kiribati might be the perfect location for dynamics of GG to get born and how, Kiribati, a country under threat and fear, can be transformed into a lighthouse of entrepreneurship which can give boost to the implementation of one of the most advanced energy technologies in the world. I also discuss how, ultimately, a “least developed economy” can secure scientific lessons, which are highly significant for the international knowledge society.