We have a number of recognized transmission and distribution experts serving on our board of "Grid Masters." Several times each month we’ll post what we judge to be the toughest questions that also have high interest to our readers. At least one of our experts will respond. Want to challenge our Grid Masters for a chance to win?

This week’s question and answer:

Q: In some HVDC projects the cable link between the converter stations consists of two sections, a sea cable section designed with copper conductor and a land cable section designed with aluminum conductor. What is the purpose of such a configuration?
Anon (Sweden)

A: It's a matter of economics. Even though a larger conductor cross section is needed for the same capacity due to its lower conductivity, land cable with aluminum conductor costs less than land cable with copper conductor due to the difference in metals prices. Copper conductor is traditionally used for submarine cables, however, in some cases aluminum conductor may be used.

Michael Bahrman
HVDC Business Development
ABB

A: Design of the HVDC cable system considers different aspects, including installation environment (depth, thermal resistivity, surrounding material etc), economical impact on the overall project, customer preference and vendor experience. It is possible to have Aluminum conductor in the submarine application as well as Copper for land application, based on the previous statement.

Mekic Fahrudin
Director
Marketing and Sales

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