02-21-2023, 08:40 AM
In the "old" days, phone lines were made of copper and used power from the phone system (even the phone handset in your house was powered by the phone line). The benefit was that a power outage didn't effect the phone system since they were independent of each other. The disadvantage was that each phone line required its own circuit, meaning thick cables with lots of individual wires.
Now, the thick cables have been replaced with fiberoptic cables which reduces the number of individual lines between the phone system station subsystems. The downside is that the fiberoptic cables cannot be used to power the phone station subsystem. When the power goes out, the substation has a battery backup, but that lasts only for so long. That battery backup needs to supply power not only for the equipment in the substation, but also sends power to the individual lines going to each house (you can still have an old fashioned phone in your house). Battery backups do not last that long. A generator could be used as well, but would require fuel.
Now, the thick cables have been replaced with fiberoptic cables which reduces the number of individual lines between the phone system station subsystems. The downside is that the fiberoptic cables cannot be used to power the phone station subsystem. When the power goes out, the substation has a battery backup, but that lasts only for so long. That battery backup needs to supply power not only for the equipment in the substation, but also sends power to the individual lines going to each house (you can still have an old fashioned phone in your house). Battery backups do not last that long. A generator could be used as well, but would require fuel.