Wave Energy
Author: Jonathan Soencer-Jones ~ Editor, ESI Africa Magazine
( Article Type: Explanation )
The marine environment is the next major frontier for the harnessing of energy, with vast amounts of energy potentially available in the waves (driven by the wind) and tides (driven by the moon) of the seas worldwide. Although records are known dating back to the 12th century of tidal energy being exploited for milling purposes, the development of marine energies has lagged behind other renewables because of the difficulty of installing systems in the sea. 
However, this is changing as technological developments in marine renewables are picking up pace.
Novel designs range from buoys and other floating devices, from which the energy is captured from their up-down movement in the waves, to seabed-mounted turbines, which rotate due to the action of the current on the blades, but most have yet to proceed beyond the prototype or demonstration stage. The world’s first commercial wave power project, the LIMPET (land-installed marine power energy transformer), which captures the energy in shore-breaking waves, is installed on the Scottish island of Islay and began feeding power into the grid in late 2000.
A study of the wave power off Cape Town was undertaken at the University of Stellenbosch in the early 1980s, finding that the inshore potential along the southwestern Cape coast is as promising as anywhere else in the world. In 2002, as part of Eskom’s renewable energy programme, an assessment of the wave power potential of the whole South African coastline was completed, indicating that the potential is greatest off the southwest coast between Cape Town and Mossel Bay. The second phase of the programme, currently underway, is aimed at identifying a suitable technology for use in South Africa. The Oelsner Group has also been investigating wave energy from an independent power producer perspective and is involved in an economic feasibility study of a seabed device that was developed in a University of Stellenbosch study. The Oelsner Group, in conjunction with Interproject Service AB of Sweden, is also involved in developing a project to supply wave power to Robben Island from a moored buoy system just off the Island.
