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.

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.

Green water occurs when an incoming wave exceeds the freeboard and propagates onto the deck of naval/offshore structures, such as floating production storage and offloading units and platforms. This water can affect the integrity of facilities and equipment that are installed on the deck, compromise the safety of the crew, and affect the dynamic stability of the structure. Traditionally, wave trains have been used to study the green water problem, which is a good approach to analyzing consecutive green water events. However, to carry out systematic studies that allow local details to be identified for different types of green water, an alternative method is to study isolated events generated by a single incoming wave. The purpose of this paper was to experimentally investigate the generation of different types of isolated green water events using the wet dam-break (DB) approach as an alternative to generating the incoming wave. Tests were carried out in a rectangular tank with a fixed internal structure. Different freeboard conditions were tested for two aspect ratios of the wet DB ($h0/h1=0.40$ and 0.6). Conventional wave probes were used to measure the water levels in the tank, and a high-speed camera was set to capture details of the generated green water events. The results demonstrated the ability of this approach to represent different types of green water, similar to those obtained with unbroken regular waves in barge-shaped fixed structures, including DB, plunging-dam-break (PDB) and hammer-fist (HF).