One of the most challenging tasks in the effort to distribute power, is to transmit when the area is bounded by bodies of water. Examples of this are island states or countries, and their connection to the power grid, as to support their island mode generating capacities.
Under normal circumstances, long distances and the presence of water beneath limits the practicality of putting overhead lines for the purpose. Thus, most of the time, engineers and builders turn to submarine cables.
Submarine cables are cables that are laid beneath the sea, or any bodies of water to carry or transmit energy, data or both. It can be classified into Submarine Communication Cables or Submarine Power Cables.
Typical cross section of a submarine cable is wonderfully illustrated by this picture courtesy of http://www.mutual-energy.com/The_Moyle_Interconnector/History_and_Development_of_the_Interconnector.php
For more on submarine cables, check and click on these highly recommended free tutorials, free links, and submarine cables pdf:
LINK 5 Submarine Cable Laying and Installation Services For the Offshore Alternative Energy Industry
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