Think of how many cell towers there are.
Each one consumes a couple hundred watts in transmitter, bridging equipment, tower lighting, and shed lighting.
It wasn't long ago that if you wanted to have a lighted dial on your telephone dial/keypad, you had to have a transformer plugged in to some AC outlet in your home. The phone lines didn't carry enough power for the incandescent lights. Today, LEDs serve that function without requiring transformers.
Also, what few "big iron" phone company switches that still exist are powered independently, through those banks of batteries and generators, and from the normal electrical grid -- not through the trunk lines.
Phone lines have a -48V operating current, and 96V is used to send a ring. |
