A group of researchers from Florida Atlantic University completed the most far-reaching in history study to identify the areas most fit for receiving energy from sea currents. Their objective was to identify the areas where the strength of ocean currents is so high and so stable, that it may become the source for generating clean renewable energy. To do that, the researchers analyzed the data collected during several decades via drifting buoys in different parts of the World Ocean, mainly in the Indian Ocean, and also in the Atlantic and in the Pacific. Overall, there are 1,250 such buoys all over the world; they are not dependent on the winds, they are freely drifting with the currents, they continuously measure the speed and the vector of the water flow and transmit this data via satellite.
43 mln of measurements were collected during the entire period of observations. This provided for the possibility to calculate the so-called energy density, i.e., to identify the amount of potential electricity in each square meter of water in different parts of the ocean. For the first time, this analysis allowed to identify the areas with the highest electricity potential with a high degree of accuracy. The areas close to the shores of Somali, Kenia, Tanzania, Madagascar and South Africa were recognized as the most promising. In some areas, the power density reached from 500 to 2,500 W per sq. meter — these values exceed the threshold used for classification of wind energy sources as “excellent”.
By way of illustration: an average small household in South Africa consumes circa 730 W of electricity. It means that just one square meter of ocean surface with such energy density could cover the needs of such household. This makes sea energy potentially very feasible and environmentally clean solution for African countries, especially against the background of climate change and the need to switch to RES.
Nevertheless, the scientists emphasize that additional research is required fully implement such projects. In particular, a shorter historic data is available for the Indian Ocean: here, the measurements have been taken starting from 1994, while as in the Pacific Ocean — starting from 1979. In addition, certain high-potential areas are located on the depth of 1,000 meters, and that technically impedes the installation of subsea turbines. However, there are zones where powerful currents are closer to the shore on the depth up to 100 meters — and such zones may be recognized as better fit for the initial implementation of these technologies.
