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A comment on Israel, Cyprus and Greece agree to link power grids via subsea cable. Parent comment

Re:Israel, Cyprus and Greece agree to link power grids via s... by gmueckl on Monday March 08, 2021 @11:46AM (#26387842)
Saltwater is a very poor dielectric between wires (it is a high resistance conductor actually). An AC line would have a low efficiency because the dissolved ions transport a leak current between the wires. Around a DC line, electric field just generates an ion gradient once when powered on (and assuming the insulation doesn't experience electrolysis).

Long AC lines in air also have a finite resistance between wires, but it is much higher and not much of a concern.

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Re:Israel, Cyprus and Greece agree to link power grids via s... by koheripbal on Monday March 08, 2021 @05:32PM (#26392564)
Does a long distance DC line even need a negative wire, or can you just connect it to ground at the destination?
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Re:Israel, Cyprus and Greece agree to link power grids via s... by tim333 on Tuesday March 09, 2021 @09:35AM (#26399136)
They can work without a return wire. It sounds like this system is designed to be able to work that way in case of faults:

>The use of two HVDC cables will provide the link between all four sites. The use of two cables constitutes the bipolar operation of the project. A return path through earth, however, is provided in order to allow for the reinstatement of rated or half-rated power transfer through converter switching, in case of faults and disconnections of one of the two 500MW elements of the converter, or one of the two HVDC cable links.

(https://www.euroasia-interconnector.com/wp-content/uploads/2... p17)

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Re:Israel, Cyprus and Greece agree to link power grids via s... by spectralwarp on Monday March 08, 2021 @06:46PM (#26393249)
https://en.wikipedia.org/wiki/Single-wire_earth_return
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Re:Israel, Cyprus and Greece agree to link power grids via s... by simonebrunozzi on Monday March 08, 2021 @04:43PM (#26392041)
Upvoted, and let me add: what a fantastic comment - deep and clear and easy to grasp.
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