The sun always rises

The telephone business ain't what it used to be!

Since 2000, U.S. telcos have lost about a third of their access lines. They have replaced only half of the 60 million lines lost with broadband access lines and only about 2 million with broadband lines capable of delivering triple play.

Then again, a telco's network is still, mostly, what it used to be!

U.S. telcos own thousands of central office (CO) buildings, most chock-full of 1980s-vintage circuit switching equipment — about twice what's needed for lines in service today.

CO equipment uses DC power, which means power from the AC grid must be converted to DC by rectifiers and then distributed throughout the building by a network of busses and cables. Most CO power systems were designed in the '70s and installed in the '80s. Many feature ferroresonant rectifiers, renowned for their durability and reliability but not for their efficiency.

Part of the AC power coming into the CO is wasted by conversion inefficiencies in the rectifiers. Even more power is dissipated as heat by the equipment in the CO, forcing the telco to buy more AC power for air conditioning. Telcos are cramming new broadband equipment into COs, which consumes more power and dissipates more heat than the old circuit equipment. Somehow, telcos never get around to removing any of the old equipment that's no longer doing anything but taking up space, using power and giving off heat.

Verizon used 8.9 billion kilowatt hours, costing about $900 million, to operate its network in 2006. Energy prices are rising, so Verizon is within sight of a billion-dollar annual opex bill to power its network. I roughly calculate that the equipment in a middling-sized CO draws about 1000 amps at -48 VDC, or 50 kW. That's more than 400,000 kWh per year, not counting the power required to cool the building and turn on the lights.

To their credit, telcos are paying more attention to power. Verizon recently announced that the products it buys in 2009 and beyond will be required to consume 20% less power than those it buys now. That's got the supplier community scrambling. AT&T has taken a leadership role in ATIS' energy initiatives and joined “The Green Grid” to push for power efficiency in data centers. Other big telcos, such as Embarq, are getting on board with energy reduction and conservation programs.