A proposed high voltage electrical cable running across the floor of the North Atlantic Ocean to tap Iceland’s surplus volcanic geothermal energy would become the world’s longest underwater electrical cable, if it goes ahead. The cable would be a significant step towards a pan-European super grid, which may one day tap renewable sources as far afield as Scandinavia, North Africa and the Middle East. It’s argued that such a grid would be able to widely transmit energy surpluses from active renewable sources, thereby alleviating the need for countries to use (or build) back-up fossil fuel power stations to cater for peaks in demand when more local renewable sources aren’t particularly productive. If a European super grid comes to fruition, energy surpluses will be big business. So it’s hardly surprising that both Germany and the United Kingdom are jostling for position at the other end of the Icelandic cable, with Norway and the Netherlands also having been mooted as potential connectees. That would necessitate a cable at least 745 miles (1198 km) in length, making it easily the longest electrical cable in the world

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Plans afoot to tap Iceland’s geothermal energy with 745-mile cable