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> I strongly doubt there are any non-fiber submarine cables. I strongly doubt electrical cables are fiber cables for example :-) On a more serious note, I was

by hnarn 5y ago

> I strongly doubt there are any non-fiber submarine cables. I strongly doubt electrical cables are fiber cables for example :-) On a more serious note, I was thinking that there are perhaps copper cables used for telephone communications that are still used simply because they haven't yet failed, but I assume fiber has perhaps been the standard for backbones long before it became something people have in their homes.

jhgb 5y ago
Wouldn't it make sense for some electrical cables to have some fiber in them? When you're already laying them, you could get two services for the price of one.
- hnarn 5y ago
  I suppose it would, I guess I'm just wondering for how long fiber cables have been the standard, and if there are any operational cables from the time before that. I'm pretty sure there are plenty of cables dedicated for one purpose (e.g. electricity only) that do not contain fiber simply because there wasn't a need or requirement when it was planned. edit: Here's an example: > The world record from 1994, for the longest HVDC cable with the highest capacity, was equalled in 2000 with the successful completion of the Swedish-Polish HVDC transmission link between Sweden and Poland: > 1. Stretching over 250 km, it is one of the two longest submarine HVDC cables ever laid. > 2. At 600 MW, the cable is one of the most powerful HVDC cables in commercial operation. > 3. At 450 kV DC, this cable together with the cable between Sweden and Germany, has the highest voltage rating of all existing submarine HVDC cables. This cable doesn't seem to have any other purpose than transferring electricity, and it was installed "only" 21 years ago.
- dtech 5y ago
  I highly doubt it's cost-effective. These things are complicated and have specialized equipment. The endpoints also very different for data and electricity.
- cranekam 5y ago
  I'm certainly no expert here but I'm guessing it doesn't make sense for two reasons: 1) Modern communications fibers are complicated (https://en.wikipedia.org/wiki/Submarine_communications_cable https://en.wikipedia.org/wiki/Submarine_communications_cable [1]) and presumably expensive so speculatively adding them to power cables would likely be a pricey endeavor. 2) AFAIK most submarine cables are systems — e.g. a ring the connects various places so that there are two paths between points — so trying to plan one to that co-opts existing bits of fiber piggy-backed on power probably wouldn't be easy. Also you'd have the issue of dealing with different generations of fiber, standards, etc. [1] On reading this it turns out that modern fibers actually carry power as well so that repeaters en route can be powered.
- tbihl 5y ago
  In almost all conceivable contexts, no. If you've ever done any work with electrical code, you are familiar with the spacing requirements between electrical conduit and data wires to prevent magnetic interference: at least a foot apart, and perpendicular crossings if crossings are necessary. The voltage on underwater electrical cables are quite high, as is the bandwidth on underwater data cables, so you definitely can't have them mixing if you want anything near optimum results on data transfer.
  - fsckboy 5y ago
    he was asking about fiber which is not subject to electro-magnetic interference
    - midasuni 5y ago
      Even setting that aside Undersea power is DC
- cycomanic 5y ago
  Optical fibres are also pretty good sensors so it's not unlikely that some fibres are added just for sensing purposes (they are eput into lots of bridges and other things for example). That said it highly depends on the length of your electrical cables if putting in fibre for communications makes sense. Typically (grossly simplified) you need optical amplifiers when you go significantly over transmission distances of 100km so they need power supplies, take up quite a bit of space etc..
- walrus01 5y ago
  Already a thing, one of the high voltage power cables to Tasmania also has singlemode fiber in it. Not uncommon.
  - shoo 5y ago
    Shown on the map as "basslink". you can find it on the southern side of australia, it's the easternmost tiny little line crossing INDIGO central. 500 MW electricity interconnector + bonus 12 core fire cable https://en.wikipedia.org/wiki/Basslink#Basslink_Telecoms https://en.wikipedia.org/wiki/Basslink#Basslink_Telecoms
- alerighi 5y ago
  They probably already had some inside but not for general use, but to exchange data between the two ends of the cable. Modern power grid is smart, and it has data connection along side power, they do that also on overhead power lines (the upper cable beside the three phases serves as a protectoin from lightning strikes but also has a fiber inside). In practice the power network also has a completely isolated LAN (for obvious security reasons) to manage the whole infrastructure. At least in my country it's done like that.

by hnarn 5y ago

jhgb 5y ago

Wouldn't it make sense for some electrical cables to have some fiber in them? When you're already laying them, you could get two services for the price of one.

hnarn 5y ago
I suppose it would, I guess I'm just wondering for how long fiber cables have been the standard, and if there are any operational cables from the time before that. I'm pretty sure there are plenty of cables dedicated for one purpose (e.g. electricity only) that do not contain fiber simply because there wasn't a need or requirement when it was planned. edit: Here's an example: > The world record from 1994, for the longest HVDC cable with the highest capacity, was equalled in 2000 with the successful completion of the Swedish-Polish HVDC transmission link between Sweden and Poland: > 1. Stretching over 250 km, it is one of the two longest submarine HVDC cables ever laid. > 2. At 600 MW, the cable is one of the most powerful HVDC cables in commercial operation. > 3. At 450 kV DC, this cable together with the cable between Sweden and Germany, has the highest voltage rating of all existing submarine HVDC cables. This cable doesn't seem to have any other purpose than transferring electricity, and it was installed "only" 21 years ago.
dtech 5y ago
I highly doubt it's cost-effective. These things are complicated and have specialized equipment. The endpoints also very different for data and electricity.
cranekam 5y ago
I'm certainly no expert here but I'm guessing it doesn't make sense for two reasons: 1) Modern communications fibers are complicated (https://en.wikipedia.org/wiki/Submarine_communications_cable https://en.wikipedia.org/wiki/Submarine_communications_cable [1]) and presumably expensive so speculatively adding them to power cables would likely be a pricey endeavor. 2) AFAIK most submarine cables are systems — e.g. a ring the connects various places so that there are two paths between points — so trying to plan one to that co-opts existing bits of fiber piggy-backed on power probably wouldn't be easy. Also you'd have the issue of dealing with different generations of fiber, standards, etc. [1] On reading this it turns out that modern fibers actually carry power as well so that repeaters en route can be powered.
tbihl 5y ago
In almost all conceivable contexts, no. If you've ever done any work with electrical code, you are familiar with the spacing requirements between electrical conduit and data wires to prevent magnetic interference: at least a foot apart, and perpendicular crossings if crossings are necessary. The voltage on underwater electrical cables are quite high, as is the bandwidth on underwater data cables, so you definitely can't have them mixing if you want anything near optimum results on data transfer.
- fsckboy 5y ago
  he was asking about fiber which is not subject to electro-magnetic interference
  - midasuni 5y ago
    Even setting that aside Undersea power is DC
cycomanic 5y ago
Optical fibres are also pretty good sensors so it's not unlikely that some fibres are added just for sensing purposes (they are eput into lots of bridges and other things for example). That said it highly depends on the length of your electrical cables if putting in fibre for communications makes sense. Typically (grossly simplified) you need optical amplifiers when you go significantly over transmission distances of 100km so they need power supplies, take up quite a bit of space etc..
walrus01 5y ago
Already a thing, one of the high voltage power cables to Tasmania also has singlemode fiber in it. Not uncommon.
- shoo 5y ago
  Shown on the map as "basslink". you can find it on the southern side of australia, it's the easternmost tiny little line crossing INDIGO central. 500 MW electricity interconnector + bonus 12 core fire cable https://en.wikipedia.org/wiki/Basslink#Basslink_Telecoms https://en.wikipedia.org/wiki/Basslink#Basslink_Telecoms
alerighi 5y ago
They probably already had some inside but not for general use, but to exchange data between the two ends of the cable. Modern power grid is smart, and it has data connection along side power, they do that also on overhead power lines (the upper cable beside the three phases serves as a protectoin from lightning strikes but also has a fiber inside). In practice the power network also has a completely isolated LAN (for obvious security reasons) to manage the whole infrastructure. At least in my country it's done like that.