[Lazamataz]

No mention in the article of using powerlines for communication.

Educate pls.

[Southack]

Data can be transmitted over powerlines.

[JoeFromSidney]

Back during WW II, when ham radio was shut down, many hams switched to "carrier current" communications. This means transmitting over the power line network, using frequencies of a few tens of kilohertz. A problem is that the signal won't go through the transformer at the pole. Somehow you need to connect to the other side of the transformer. This may mean negotiating with the power company. However, in an emergency I think I'd ignore that little detail.

Intercoms that use the wiring in your house for the link between sets use the same principle. I once found that a neighbor, on the same side of the transformer as my house, was using one of these intercoms. We could hear each other. Fortunately my sets had several channels available. I just didn't use the same channel he was using, and avoided the interference.

[pabianice]

Gridline Communications provides internet over electrical lines.