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Although the literature on Sustainable Development Goals (SDGs) is vast worldwide, studies in Mexico focusing on Marine Renewable Energy (MRE) and SDGs are only beginning to emerge. Despite this academic gap, Mexico has signed up for the United Nations SDGs, which include producing clean and affordable energy and reducing CO2 emissions to slow global warming. The country is, therefore, committed to implementing measures to help achieve these goals. This study is the first multidisciplinary analysis performed at a national level in Mexico, aimed at identifying sites for efficient Marine Renewable Energy (MRE) production while considering socioeconomic needs, environmental risks, and societal acceptance of the new technologies. We first calculated the energy potential from nearshore winds, waves, marine currents, and offshore thermal gradients. The results show that electricity needs are greater in the 11 states where levels of marginalization are highest. The production of MRE is feasible in three of these regions. However, because Mexico is home to significant natural coastal ecosystems and protected species, care is necessary to produce electricity while protecting Mexico's megadiversity. Social perception of the use of MRE is variable: the inhabitants of some locations are willing to accept the new technologies, whereas those in others are not. MRE production in Mexico is feasible but will face environmental and social issues that must be addressed before deploying new devices in the oceans. [ABSTRACT FROM AUTHOR]

Although there are constant improvements in wave energy converter (WEC) technology, it is crucial to investigate site-specific sea conditions for optimal power absorption and efficiency. This study compares the efficiency of a floating buoy-type WEC device, with three differently shaped floats: a semi-sphere, a cylinder considered suitable for a location near Ensenada, on the Baja California peninsula, and a novel, rounded, semi-rectangular float. A statistical analysis of the wave climate of the last 42 years was performed to define the conditions to which the device is subjected. The WEC location was chosen for shallow waters, using a computational model that solves the modified mild slope equation. The hydrodynamic response of the three float designs was then analyzed in the frequency and time domains, using the software ANSYS AQWA 19.2, to assess the dynamics of the floating body, the forces exerted, and the power absorbed, as well as the suitability of the proposed power take-off (PTO) system. The findings show that the proposed float design absorbs the most energy, with an annual power of 135.11 MW, and that the PTO mechanism is appropriate. [ABSTRACT FROM AUTHOR]

Analysis of the omnidirectional energy spectrum from storm wave measurements provides valuable parameters for understanding the specific local conditions that wave energy converters would have to withstand. Partitioning the energy spectrum also helps to identify wave groups with low directional spread propagating in the direction of the dominant waves of the more energetic wave systems. This paper analyzes the partition of the Hurricane Wilma energy spectrum using single-point measurements obtained in shallow water. Hurricane Wilma generated simultaneous crossing wave systems with different significant wave heights and steepnesses. The maximum estimated significant height among the wave groups was 5.5 m. The corresponding height of the partitions and the omnidirectional energy spectrum were 11.0 m (swell) and 12 m, respectively. While linear superposition was the main mechanism responsible for driving the wave groups, at times, modulational instability produced nonlinear wave groups. This is a new finding, since modulational instability is usually considered an open-sea phenomenon. For shorelines with multidirectional wave groups, submerged and semi-submerged devices should be designed to account for changes in wave direction and wave height, although under extreme hurricane conditions, energy harvesting might have to be sacrificed for the benefit of device integrity. [ABSTRACT FROM AUTHOR]

The numerical performance of a buoy-type wave energy converter (WEC) under regular wave conditions is described in this paper. The open-source computational fluid dynamics software OpenFOAM® was used to couple a grid for the solid body motion of the WEC, with the grid designed for wave propagation, in order to calculate buoy movement parameters. The buoy has a horizontal, cylindrical structure, with a pivot point for semi-axis rotation. Five buoy-radiuses were analyzed, as this parameter considerably increases the efficiency of the WEC point absorber. To better understand the interaction of the WEC with the waves, the transmission and reflection coefficients were calculated, along with two non-linear parameters: skewness and asymmetry. The results indicate that, with this system, more power can be extracted from shorter waves, T = 4 s, compared to T = 8 s of the same wave height. This implies that a small buoy could be employed at sites with this prevailing wave regime, without a decrease in efficiency and with considerable cost reductions. Finally, this WEC increases the values of wave skewness, which is linked to onshore sediment transport; therefore, if appropriately designed, WEC arrays installed near the coast could also promote onshore sediment transport. [ABSTRACT FROM AUTHOR]

Establishing a renewable marine energy industry demands the development of high-efficiency devices that capture as much energy as possible. The Blow-Jet is a wave energy converter mainly composed of a sloping conical channel in the shape of a brass tube, which concentrates the waves at its widest part and expels a jet of water at its narrow upper end through an orifice that can be turbined. The device has no moving parts and great flexibility in its placement. This research presents an improvement of its geometry, increasing efficiency by minimizing undesired hydrodynamic interactions. The performance of the Blow-Jet was characterized using 3D numerical modeling and laboratory tests in a wave flume. Sixteen geometric configurations of the Blow-Jet were numerically tested, and that showing the best performance was 3D printed and assessed experimentally. The twofold objective was to evaluate the performance of the new Blow-Jet geometry and to validate a numerical tool for further geometrical improvements of the device. The novel geometry is nearly 20% more efficient than the original. [ABSTRACT FROM AUTHOR]

Increasing demand for electricity and the need for sustainable energy sources, make ocean energy a viable alternative for its generation in coastal regions. In this study, wave, marine currents and thermal gradient resources were evaluated to identify potential sites for energy harvesting in the Mexican Caribbean. From a techno-economic review of the literature, a marine current turbine from Nova Innovation 100 kW, an OWC (350 kW), and an OTEC (1 MW) plant were considered, examining theoretical energy potentials and the LCOE of each. A potential environmental impact assessment was also carried out, including a study of the regulatory framework and the socio-economic conditions in the region. The results show that energy harvesting from the sources analyzed is viable, especially in the north of the area, where most of the sites that fit the proposed criteria were found, e.g. Cancun for wave energy (power availability of 45.6 MWh/m/yr) and current energy (power availability of 4.4 MWh/m²yr), and the east coast of Cozumel for OTEC deployment (power availability of 1.69 GWh/km2/yr). Of the three harvesting technologies studied, the best LCOE obtained was for OTEC (862.2 US$/MWh) with a capacity factor of 0.965%. This was expected, given that the technologies analyzed for current and wave energy are not efficient for the resource conditions in the Mexican Caribbean. [ABSTRACT FROM AUTHOR]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Odériz, I.; Gómez, I.; Ventura, Y.; Díaz, V.; Escalante, A.; Gómez, D.T.; Bouma, T.J., and Silva, R., 2020. Understanding drivers of connectivity and resilience in coastal ecosystems experiencing tropical cyclones. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 128–132. Coconut Creek (Florida), ISSN 0749-0208. A better understanding of ecosystem connectivity and resilience is needed to establish efficient conservation strategies for coastal ecosystems. Physical maritime processes are key drivers for ecosystem connectivity in the Caribbean, where there is low wind and wave energy for most of the year but also short, extreme meteorological events. The energy peaks induced by tropical cyclones and the long calms are important for biodiversity. Climate change projections suggest that while there may be fewer tropical cyclones here, their intensity will increase. This paper analyses the effect of tropical cyclones on ecosystem resilience, studying both the potential connectivity and damage of mangrove, vegetated dune, seagrass and coral reef ecosystems at Puerto Morelos, Mexico. A numerical modelling approach was used to evaluate the spatial-temporal ecosystem connectivity and damage induced by hydrodynamic processes between 2005 and 2018, taking into account, wave, storm surge patterns and modifications in the vegetation cover following tropical cyclones. From our results, it was found that the balance of connectivity-damage to the intensity of the tropical cyclones depends on healthy ecosystems and the characteristics of geomorphology, with coral reef-seagrass-mangrove being more resilient to the increase in wave height but less resilient to the sea level rise. Open beaches with dune-mangrove was less resilient to the increases of both. [ABSTRACT FROM AUTHOR]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Felix, A.; Mendoza, E.; Chávez, V.; Silva, R., and Rivillas-Ospina, G. 2018. Wave and Wind Energy Potential Including Extreme Events: A Case Study of Mexico. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp.1336–1340. Coconut Creek (Florida), ISSN 0749-0208. The available wind and wave energy potential of the coasts of Mexico was found to be low in several analyses. However, these analyses considered only average conditions. To adequately assess the energy potential of Mexican coasts for energy extraction, it is necessary to characterize maritime weather and to define both normal and storm thresholds. For the present study, a 60-year historical analysis of wave and wind conditions along the Mexican coasts was performed. A statistical analysis of extreme conditions was carried out using the peaks-over-threshold approach. Also, seasonal (winter, spring, summer and autumn) and hourly available power were included in the analysis. The differences between the energy potentials when including and excluding extreme events are considerable. The energy potential of events occurring along the Mexican coasts confirms that energy can be adequately and profitably obtained from waves and wind. The greatest energy potential in the Atlantic is found to the northeast of the Yucatan Peninsula and in the Pacific along the Baja California Peninsula. Winter is the best season for energy extraction, while summer is the most unfavorable season. [ABSTRACT FROM AUTHOR]

Abstract: One of the greatest challenges of coastal engineering today is the need for coastal protection in the changing climate scenario. Places which are nowadays protected will demand upgraded defences and more sites will require security; in all cases a large amount of resources will be needed to ensure beach maintenance and coastal safety. This may be an opportunity for the multi-purpose use of Wave Energy Converters (WECs) if the foreseen increase of energy demand in coastal areas is also considered. In this paper a group of WECs based on different operating concepts is numerically tested in front of two beaches, i.e. the Bay of Santander in Spain and Las Glorias beach in Mexico, representing two different case studies where the long-shore sediment transport is dominant. The hydrodynamics induced by these devices is represented by means of a 2D elliptic modified mild-slope model that is calibrated against new experimental results. The wave field is then used as input for the analytical calculation of the long-shore sediment transport and the coastline trend is estimated by applying the continuity of sediment equation. The characteristics of the selected numerical models give this work a first approach level. All the devices were found to produce a positive trend (accretion) at least in small areas. Recommendations are given to facilitate the selection of the device and the design of the farm layout for shore protection purpose. [Copyright &y& Elsevier]

Coastal dunes are very important, for both their ecosystem services and their ecological importance. A quantification of the area occupied by dunes was made for all of the Mexican Caribbean coast, and a qualification was assigned, according to the type of dune, its height and condition. 4981 ha of coastal dunes were identified on the coast, with heights of 1 to more than 10 m above mean sea level. Offshore wave climate was evaluated, showing relatively constant characteristics all along the coast. Aeolian drift potential was calculated and was found to be unrelated to the height of the dunes. The empirical relationship between coastal ecosystems (coral reefs and sea pastures) and the characteristic of the dunes are promising. The interconnectivity of ecosystems adjacent to coastal dunes, such as seagrass, coral reef and mangroves, affects the conditions of incident wave energy and/or the transport and availability of marine sediment. In the Mexican Caribbean, these ecosystems often exist parallel to one another, and their interrelationships could explain the variability of coastal dune height. It was observed that where the coast is protected by a coral barrier reef (less than 1000 m from the shore, with a crest at less than 2 m depth) and seagrasses, the foredunes are lower (under 2 m height) than those in more exposed areas, without coral reef protection (foredune height more than 10 m). A conceptual model was proposed to explain the size of the dunes in the study area, based on the characteristics of adjacent ecosystems (presence, distance from coastline, height of water column above corals and/or seagrasses) and the submerged morphology of the area. • 4981 ha of foredunes were identified in the Mexican Caribbean • Foredune heights of 1 to 13 m shows great variations • Foredune heights are not related to wind transport or offshore marine dynamics • Coral reef and seagrass characteristics are related to foredune height • A conceptual model explains the relation between coral, seagrass and foredune height [ABSTRACT FROM AUTHOR]

The harnessing of renewable sources of marine energy has become a promising solution for a number of problems, namely satisfying the increasing demand for electricity, the reduction of greenhouse gas emissions, and the provision of energy to regions unconnected to a national grid. Tropical countries have an interesting dichotomy: Despite their varied potential sources of marine energy, their environmental and social conditions impose severe constraints on the development of a renewable energy industry. Moreover, the exploitation of these opportunities is limited by national economies' reliance on fossil fuels, political and social restraints, and technological immaturity. The present work addresses challenges and opportunities common to wave energy implementation in tropical nations, as a first approach to a regional diagnosis. The motivation for this work is to encourage research on wave energy policies in the Tropics. Technical, environmental, and social challenges to be overcome in wave energy projects are discussed. The technical challenges are grouped into development, deployment, and operation stages of wave energy converters; environmental challenges are divided into biodiversity, cumulative effects, and monitoring aspects, whilst social issues include population growth and energy access matters. The Mexican strategy for developing sustainable technology throughout the wave energy production chain is also presented. [ABSTRACT FROM AUTHOR]

The Atlantic and Pacific coasts of Mexico offer a variety of marine energy sources for exploitation. Although the Mexican government has made important efforts to reduce its dependence on fossil fuels, national participation in clean energies is still limited in terms of electricity production. This paper presents a practical theoretical assessment of marine energy sources around Mexico, with the aim of identifying potential zones for subsequent, more detailed, technical evaluations and project implementations. The energy sources considered are ocean currents, waves, salinity, and thermal gradients. Using global databases, the percentages of energy availability for the defined thresholds were computed to establish the prospective regions with the most persistent power availability. This approach proved to offer more meaningful information than simple averaged values. Moreover, some environmental and socio-economic factors to be considered for future ocean energy resource assessments in Mexico were also discussed. The results show that the wave energy potential is highest in the northwest of Mexico (~2–10 kW/m for more than 50% of the time), and that there is a constant source of ocean current energy off Quintana Roo state (~32–215 W/m2 for more than 50% of the time). The thermal gradient power is more persistent in the southwest and southeast of the country, where ~100–200 MW can be found 70% of the time. The salinity gradient energy is strongest in the southeast of Mexico. The practical approach presented here can be extended to perform preliminary resources assessments in regions where information is scarce. [ABSTRACT FROM AUTHOR]

Wave power is affected by long-term fluctuations induced by natural variability. However, long-term variability has not yet been integrated into the wave energy quantification and the design of wave energy converters. The present study aims to develop a comprehensive assessment of wave energy harvesting based on different time scales in La Serena, an energetic region of the Chilean Pacific. For this purpose, the ERA5 hindcast wave dataset was validated with Global Wave altimetry data. The wave data for the bay of La Serena were reconstructed through a hybrid method, based on a sea-state selection algorithm a wave numerical propagation model (SWAN), and radial basis function interpolation. This methodology considers the entire climate casuistic, which allows identifying and analysing potential sites for wave energy converters deployment. The selected hotspots of interest are assessed by comparing energy accessibility, temporal variability, and different indices through a quantitative evaluation. The mean annual wave power availability at La Serena Bay reaches ∼24 kW/m with a low-moderate seasonal variability, between +2 kW/m and −5 kW/m, with a coefficient of variation of 0.61. The selected site of highest accessibility is located in the shallow southern location, with a mean annual wave power of ∼25 kW/m and a coefficient of variation of 0.84. The local wave climate responds to El Niño-Southern Oscillation. During La Niña, the annual wave power in the region increases, with winter waves reaching up to 34 kW/m. • Wave power is affected by long-term fluctuations induced by natural variability. • The Southern Pacific coasts of Chile display a significant response to the ENSO climate mode. • The most potent energy outputs were noted and extracted during the La Niña phase. • Nearshore areas with greater depths in the bay can reduce the costs connected to the city's electrical interconnection. [ABSTRACT FROM AUTHOR]

Coastal dunes can provide protection from flooding during extreme weather events. As such, consideration should be given to strengthening the protective mechanisms of dunes. Vegetation has recently been seen as an important factor influencing erosion processes on dunes. Another means of dune reinforcement is the installation of internal structures within dune systems. The purpose of this work is to investigate the potential utility of both vegetation and an internal rocky structure as reinforcing factors on dunes, and explain how they differentially dissipate wave energy and influence the morphodynamic response of the dune profile. This work consists of a series of experiments on dune profiles, with and without an inner rocky structure, and with two different distributions of live Ipomoea pes-caprae plants of the same density, under storm conditions. The results showed that when vegetation was at forward positions on the dune, it decreased run-up, increased reflected energy and transferred it to low frequency bands, and reduced the eroded volume on the exposed dune face. When the vegetation was placed on the leeside of the dune, it retarded and prevented overwash, but not as efficiently as the internal rocky structure did. In summary, plants are better to dissipate waves and provide protection during the initial swash and collision stages of a storm, while a rock structure is better to prevent overwash and dune destruction during the final stages. While it is possible to use both means together, for maximum protection, dune managers should weigh the financial and ecological costs according to each unique project location. • Reinforcement of coastal dunes by plant can help reduce beach and coastal dune erosion as well as shoreline retreat. • Reinforcement of coastal dunes by plant increases and maintains the resilience of coastal zones. • Reinforcement of coastal dunes by plant is an alternative ecosystem based solution. [ABSTRACT FROM AUTHOR]

A numerical assessment was made of the hydrodynamic performance of a fixed Oscillating Water Column (OWC) device based on a Helmholtz resonator under regular and random wave conditions. The associated boundary value problem (BVP) was solved using the multi-domain three-dimensional boundary element method (BEM). Two configurations of the OWC device were evaluated: cylindrical and rectangular, and the effect of the neck design on the hydrodynamic performance for each was studied under regular wave conditions. Then, specific chamber configurations are selected to analyse their annual average plant efficiencies under the sea conditions of three sites that are suitable for OWC installation. The results showed that changing the neck parameters can significantly improve the hydrodynamic efficiency of the OWC device for various wave periods. Furthermore, the yearly average plant efficiency might be negatively impacted by low turbine damping, and a rise in air column height does not always correspond to a decrease in efficiency, as this can also depend on the neck submergence. Finally, it was found that the Helmholtz resonator-based OWC device can perform well in terms of power conversion for the relatively higher wave periods commonly found at the sites of interest. • The OWC device resonates at a frequency determined by the dimensions of the neck. • The hydrodynamic efficiency with a shorter-breadth OWC was significantly improved. • This type of OWC device's power conversion may be suitable for real-world sea states. [ABSTRACT FROM AUTHOR]

The testing of scale models is crucial if we are to continue the development of wave energy converters. Investigations have examined the interaction of shore-based Oscillating Water Column (OWC) devices with regular water waves that impact the device perpendicularly in flumes or wave basins. However, these simplistic experiments might misrepresent the effectiveness of an OWC system. This study examines the interaction of irregular, oblique, water waves with a shore-based OWC device in terms of its hydrodynamic performance. In a spectral wave basin, a series of experiments were performed on a scale model of a single chamber of the Mutriku Wave Energy Plant. Wave propagation conditions were examined to see their impact on the hydrodynamic performance of a fixed OWC system. The wave amplification factor, hydrodynamic efficiency, non-dimensional air pressure inside the chamber, and non-dimensional water pressures on the chamber walls were evaluated. The results show that when the free surface is close to the front wall lip, the hydrodynamic efficiency increases, while the effect of significant wave height was seen to be more important in the wave amplification. Finally, it was found that the hydrodynamic efficiency under random waves is lower than that in experiments under regular waves reported previously. • An increase in water depth can reduce the OWC hydrodynamic performance. • The direction of incident waves affects the wave amplification within the chamber. • Incident wave height influences air pressure inside the chamber. • The hydrodynamic performance of an OWC in random waves is less compared to when exposed to regular waves. [ABSTRACT FROM AUTHOR]

The work presented here focuses on evaluating the interaction between ocean waves and a device designed to harness their energy. The device, called Blow-Jet, consists of a narrowing structure that concentrates waves and transforms their energy from potential and kinetic to kinetic, turning the oscillatory flow into an intermittent jet that can be easily guided to an impulse turbine. The new device is designed to feed low energy demands such as secondary fuel generators (e.g. hydrogen production). Several experimental tests were carried out to investigate the hydraulic behavior of the Blow-Jet. Results indicate that even for low energetic wave trains, the device is able to capture energy and amplify the water velocity, which is indeed energy conversion capacity. In order to evaluate the flow field inside the device, a high resolution 3D numerical model OpenFOAM is utilized. Good agreement was found between the pressures exerted to the walls of the device with that computed with the numerical tool. The combination of numerical and experimental results confirmed the optimal geometry, location and position of the Blow-Jet, while the need for some geometric changes was detected after the analysis of numerical model results. The Blow-Jet has shown itself to be a potential WEC with acceptable efficiency. [ABSTRACT FROM AUTHOR]