How it works (or won't work) (Score 3, Interesting)

They had this when I lived in Germany. The deal isn't that they sent a signal over the HV wires. The HV wires come into the local tranformer and get stepped down to the right voltage and smoothed out. At that point you can have a bypass to filter out the higher frequency signal that carries your packets. So from the house to the transformer you can have one set of signals riding on a normal 220 V 50 Hz (+/-) power. At the bypass, you can change the frequency so it can travel over the high voltage lines or can send it over to fiber from the tranformer to a central location. The difference between Germany and the States is that in Germany, they have a transformer that services an entire neighborhood. So you can put in the equimpent at the transformer and have potentially thousands of customers to regain the costs. In the States, there may be a neighborhood transformer, but there are also generally transformers every few houses for the final conditioning. That means expensive equipment that needs to be recouped over a small number of people.