The geographical location of Mauritius near the warm tropical waters of the Indian Ocean coupled to the vast exclusive economic zone approximating 2.3 million square kilometers, encourage the promotion of ocean thermal energy conversion (OTEC) systems. Technological advancements have enabled offshore structures to pump the cold water lying at 1000 m depth in the seawater column to the surface, and through the temperature difference set up with the warm surface layer, drives a turbine and generates electricity. In this study, a model has been developed to compute the temperature difference between the deep (1000 m) and surface (20 m) seawater layers around Mauritius. An algorithm has been implemented to determine the net power generated from a proposed OTEC power plant, acquired through the processing of sea surface temperature satellite images, at a resolution of 1 km. The spatial and temporal variations of the net power generated has been observed by splitting the annual data into four monsoonal time frames. Results show that the south-western region of Mauritius possesses high OTEC resources, with annual mean daily net power generation capacity of about 95 MW, representing about 20% of the peak power demand of the island. Moreover, the bathymetry of the southern region is propitious due to deep cold water availability at a proximity of less than 5km from the coastline. The energy and exergy efficiencies of the OTEC system are found to be 1.9 and 22.8%, respectively. A cost-benefit analysis indicates that profits of the order of 4.5 times the initial investment can be generated.

Waves are the dominant influence on coastal morphology and ecosystem structure of tropical islands. The geographical positioning of Mauritius near to the Tropic of Capricorn ensures that the eastern regions benefit from the persistent southeast trade winds which influence the incoming surface waves. In this study, we present the high dependence of the wave regimes of windward offshore site on the trade winds. The higher occurrence of incoming waves in the winter season directed in the southeast direction indicates that the trade winds are more prevalent in the winter season. Storms within the extratropical South Atlantic, Indian and Pacific oceans generally propagate towards the east such that extratropical South Atlantic swell energy spreads through the entire Indian Ocean. Since waves are very directional and tend to get shadowed by land masses, Mauritius situated in the line of sight from those sources end up in the shadow region due to the geographical location of Reunion island. In this study, we support the explanation on how the western region of the island gets influenced by episodic swell events. A detailed wave energy resource assessment is provided for different targeted coastal environments around the island. It is revealed that the mean wave power observed in the summer season at one of the sites can attain 28.8 kW/m and is found to be lower as compared to the winter season (31.7 kW/m).

No abstract