Deployment of powerline systems (low-voltage communication) for WAN access requires new equipment at every electrical substation of the energy supplier. The subscriber must be within the rather short and tight distance restrictions of a few hundred meters. Powerline intrinsically is a shared-access technology as well and delivers an Ethernet/USB interface as a demarcation point.
Powerline itself, although initially difficult to deploy, offers the opportunity of new and exciting services: LAN-only powerline in-house cabling, energy management, and remote control of electrical home equipment, just to mention a few.
Deployment of T1/E1 symmetrical bandwidth is common. For a technology overview, go to http://www.ipcf.org/powerlineintro.html.