Ocean Current Dynamics and Renewable Energy from the Agulhas Current

Authors

  • Eckart Schumann

    Department of Geoscience, Institute for Coastal and Marine Research, Nelson Mandela University, Gqeberha / Port Elizabeth 6001, South Africa
  • Michael Roberts

    1. Department of Geoscience, Institute for Coastal and Marine Research, Nelson Mandela University, Gqeberha / Port Elizabeth 6001, South Africa; 2. School Ocean and Earth Science, University of Southampton, Southampton SO14 3ZH, United Kingdom
  • Mark Bodley

    Intelligent Energy Trust, Summerstrand, Gqeberha / Port Elizabeth 6001, South Africa

DOI:

https://doi.org/10.30564/jees.v7i4.8057
Received: 12 December 2024 | Revised: 6 January 2025 | Accepted: 13 January 2025 | Published Online: 1 April 2025

Abstract

The Agulhas Current is a major western boundary current flowing polewards on the southeast coast of South Africa. This analysis assesses its characteristics and suitability to generate power as a source of clean renewable energy. On a section of coastline some 400 km long, over a period spanning more than 5 years an extensive set of current measurements was obtained. These data confirmed that south-westward currents with a speed greater than 1.2 m s–1 occurred over more than 60% of the recorded time; such ocean current speeds compare very favourably to winds required for energy generation. These currents occurred at the continental shelf break in water depths around 100 m, in the upper 50 m of the water column. Occasional current slowdowns and reversals did occur, with the major influence coming from ‘Natal Pulses’, which are large-scale meanders in the Current that temporarily reversed the currents at the measurement sites. However, because of the surface temperature structure of the relevant water masses, such meanders can be identified in satellite imagery giving a few days advance warning of such current reversals. The characteristics of western boundary currents have been known for many years, but at Present, there is no operational system where this source of power is being utilised. It has tremendous potential for renewable energy generation, but is symptomatic of the many engineering challenges that still have to be solved to make such generation economically viable.

Keywords:

5-Year Measurement Program; Agulhas Current; Consistent Currents > 1.2 m s–1; South-East Coast of South Africa; Water Depth 100 m

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How to Cite

Schumann, E., Michael Roberts, & Bodley, M. (2025). Ocean Current Dynamics and Renewable Energy from the Agulhas Current. Journal of Environmental & Earth Sciences, 7(4), 232–245. https://doi.org/10.30564/jees.v7i4.8057

Issue

Vol. 7 , Iss. 4 (April 2025): In Progress

Article Type

Article

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Copyright © 2025 Eckart Schumann, Michael Roberts, Mark Bodley

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This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.

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