Electrical Power Generation from the Oceanic Wave for Sustainable Advancement in Renewable Energy Technologies

Environmental impact assessment of ocean energy converters using quantum machine learning

The depletion of fossil energy reserves and the environmental pollution caused by these sources highlight the need to harness renewable energy sources from the oceans, such as waves and tides, due to their high potential. On the other hand, the large-scale deployment of ocean energy converters to meet future energy needs requires the use of large farms of these converters, which may have negative environmental impacts on the ocean ecosystem. In the meantime, a very important point is the volume of data produced by different methods of collecting data from the ocean for their analysis, which makes the use of advanced tools such as different machine learning algorithms even more colorful. In this article, some environmental impacts of ocean energy devices have been analyzed using machine learning and quantum machine learning. The results show that quantum machine learning performs better than its classical counterpart in terms of calculation accuracy. This approach offers a promising new method for environmental impact assessment, especially in a complex environment such as the ocean.

Advances in technology and utilization of natural resources for achieving carbon neutrality and a sustainable solution to neutral environment

The greatest environmental issue of the twenty-first century is climate change. Human-caused greenhouse gas emissions are increasing the frequency of extreme weather. Carbon dioxide (CO₂) accounts for 80% of human greenhouse gas emissions. However, CO₂ emissions and global temperature have risen steadily from pre-industrial times. Emissions data are crucial for most carbon emission policymaking and goal-setting. Sustainable and carbon-neutral sources must be used to create green energy and fossil-based alternatives to reduce our reliance on fossil fuels. Near-real-time monitoring of carbon emissions is a critical national concern and cutting-edge science. This review article provides an overview of the many carbon accounting systems that are now in use and are based on an annual time frame. The primary emphasis of the study is on the recently created carbon emission and eliminating sources and technology, as well as the current application trends for carbon neutrality. We also propose a framework for the most advanced naturally available carbon neutral accounting sources capable of being implemented on a large scale. Forming relevant data and procedures will help the "carbon neutrality" plan decision-making process. The formation of pertinent data and methodologies will give robust database support to the decision-making process for the "carbon neutrality" plan for the globe. In conclusion, this article offers some opinions, opportunities, challenges and future perspectives related to carbon neutrality and carbon emission monitoring and eliminating resources and technologies.

Analysis of the energy-capturing characteristics of floats for point absorption wave energy generators

In this study, based on four common float shapes, the factors affecting the energy-capturing characteristics of floats are determined using mathematical models of floats moving in waves. By using the orthogonal experimental method and AQWA hydrodynamics simulations, the influence degrees of different factors on the float capture width ratio were determined through the range analysis. Based on the frequency-domain conditions, the variation trends in the float energy-capturing characteristics are summarized, and the relationships between the float energy-capturing characteristics and the resonance frequency and wave force are discussed. It was concluded that the energy-capturing characteristics of slender cylindrical floats were better at the resonance frequency, and the wave force acting on the float is not the most powerful basis to judge the energy-capturing characteristics of the float. This study’s conclusions provide some reference for the design and optimization of floats.

Graphical abstract

In this study, the energy-capturing characteristics of floats in a point absorption wave energy generator under the action of multiple factors are studied. At a higher draft depth, a “slender” float shape had a larger capture width ratio. The wave force received by the float could not be the basis for determining the float energy-capturing characteristics.

An Atlas of Piezoelectric Energy Harvesters in Oceanic Applications

Nowadays, a large number of sensors are employed in the oceans to collect data for further analysis, which leads to a large number of demands for battery elimination in electronics due to the size reduction, environmental issues, and its laborious, pricy, and time-consuming recharge or replacement. Numerous methods for direct energy harvesting have been developed to power these low-power consumption sensors. Among all the developed harvesters, piezoelectric energy harvesters offer the most promise for eliminating batteries from future devices. These devices do not require maintenance, and they have compact and simple structures that can be attached to low-power devices to directly generate high-density power. In the present study, an atlas of 85 designs of piezoelectric energy harvesters in oceanic applications that have recently been reported in the state-of-the-art is provided. The atlas categorizes these designs based on their configurations, including cantilever beam, diaphragm, stacked, and cymbal configurations, and provides insightful information on their material, coupling modes, location, and power range. A set of unified schematics are drawn to show their working principles in this atlas. Moreover, all the concepts in the atlas are critically discussed in the body of this review. Different aspects of oceanic piezoelectric energy harvesters are also discussed in detail to address the challenges in the field and identify the research gaps.

A Critical Review of Power Take-Off Wave Energy Technology Leading to the Conceptual Design of a Novel Wave-Plus-Photon Energy Harvester for Island/Coastal Communities’ Energy Needs

As the global interest in renewable energy generation continues, the need to develop new and innovative solutions is being explored every day throughout the world by researchers and innovators. Hybrid renewable energy innovations are gaining progressive interest not only because of the threat of climate change but also due to the technological advancements seen in renewables. Ocean waves have immense potential as a renewable energy source, and related technologies have advanced continuously over the past few decades. In response, this paper extensively studies wave energy converters (WECs) based on the power take-off (PTO) technique, and presents a novel hybrid wave-plus-photon energy (HWPE) harvester called Wavevoltaics, based on wave and solar energy capture systems for coastal communities’ power needs, in line with decarbonization measures. The HWPE harvester uses a simple rack-and-pinion mechanism in combination with solar cell technology to convert the wave energy into usable electrical energy in a water column structural design. This novel HWPE device can be used to provide power for lighting and gadgets for coastal communities that rely heavily on fossil fuels for their lighting and electrical needs. Later in the paper, the challenges faced in hybrid wave energy development are presented.

Performance of Linear Generator Designs for Direct Drive Wave Energy Converter under Unidirectional Long-Crested Random Waves

For generating electricity, direct-drive wave energy converters (WECs) with linear permanent magnet generators (LPMGs) have advantages in terms of efficiency, simplicity, and force-to-weight ratio over WEC with rotary generators. However, the converter’s work under approaching-real wave conditions should be investigated. This paper studies the performance of a pico-scale WEC with two different LPMGs under unidirectional long-crested random waves. Different significant wave heights (using data in the Southern Ocean of Yogyakarta, Indonesia) and peak frequencies are tested. The JONSWAP energy spectrum is used to extract the wave elevations, while the MSS toolbox in MATLAB Simulink is employed to solve the floater’s dynamic responses. Next, the translator movements are extracted and combined with the flux distribution from FEMM simulation and analytical calculation, and the output powers are obtained. An experiment is conducted to test the output under constant speed. The results show for both designs, different tested significant wave height values produce higher output powers than peak frequency variation, but there is no specific trend on them. Meanwhile, the peak frequency is inversely proportional to the output power. Elimination of the non-facing events results in increasing output power under both parameters’ variation, with higher significant wave height resulting in a bigger increase. The semi iron-cored LPMG produces lower power loss and higher efficiency.

A Mathematical Model for the Optimization of Renewable Energy Systems

The generation of energy from renewable sources is a fundamental aspect for the sustainable development of society, and several energy sources such as solar, biomass, biogas, and wind must be used to the maximum to meet existing needs. In Chile, there are villages that are off-grid. A real case study is presented in this research. To meet the needs of this village we have proposed a mathematical optimization model using a CPLEX optimizer to generate the necessary energy power while minimizing the cost of energy (COE). In this study, different scenarios have been evaluated with respect to the existing energy availabilities, for example, in different periods of the year, demonstrated in terms of economic costs, the viability of resources such as biomass and biogas, and the viability of the energy production of wind power given the associated high costs. Finally, the effect of the use of renewable energy in consideration of CO2 emissions is studied in our research.

Comparative Assessment of Different Modelling Schemes and Their Applicability to Inland Small Reservoirs: A Central Europe Case Study

Sustainable landscape management involve also water reservoir management. The demand of their reconstruction represents a good opportunity for redesigning hydrotechnical structures and their parameters using recent methods and models. The estimation of wind-driven waves on small water reservoirs and their effects on water reservoir structures rarely are applied, although it is an important part of the dam height calculation. The analysis of wave run-up on the upstream face of the dam was performed by means of the Slovak Technical Standard (STN), Coastal Engineering Manual (CEM), Shore Protection Manual (SPM) and model designed by American Society of Agricultural and Biological Engineers (ASABE). The estimations of the wave characteristics differ depending on the model; wave height (H13%) within the range 0.32–0.56 m, wave period 1.32–2.11 s and run-up (R2%) 0.84–1.68 m under conditions of design wind speed 25 m·s−1. Results obtained by CEM, SPM models predict lower values than STN and ASABE models. Since the height difference between the dam crest and still water level in the reservoir is only 0.90 m, we can expect overtopping of the crest by waves after the critical wind speed is exceeded.

Differences in Electricity Generation from Renewable Sources from Similar Environmental Conditions: The Cases of Spain and Cuba

In order to achieve the objectives set by the Sustainable Development Goals and the Paris agreement, the legislative framework that is developed at the national and regional level must be appropriate. Research has focused on the importance of environmental policies to stimulate renewable energy demand and has also highlighted the existence of legal regimes more inclined to preserve the current model of dependence on fossil fuels. The main aim of this paper is to observe the impact of different regulation framework in the use of renewable energies in electricity generation. The choice of Spain and Cuba was based on several reasons: first, they present different models of legal regulations for renewable energies, with more centralized power in the case of Cuba and more influence of supranational institutions in the case of Spain; second, they have similarities regarding their productive model (highly dependent on hydrocarbons as sources of electricity generation) and the high potential for electricity generation with renewable energies thanks to their rich natural endowment that could favor energy generation from sources like the sun, wind and water; finally, both countries face a global situation where they could take advantage of this cost-cutting moment, and therefore, of electricity tariffs, to propose a sustainable model of electricity generation based exclusively on renewable energies. The conclusions show that Spain can become a role model to improve the Cuban system, given that the European and Spanish “green” positions can be very useful in developing Cuba’s future energy model based on renewables. The existing ties between the Caribbean country, Spain and the European Union (EU) should be the basis to support a model for which Cuba has an outstanding endowment of natural resources and where the similarities with Spain can generate synergies based on the European experience.