Green Telecom Part V: Emerson’s comprehensive approach

The purpose of Energy Logic for Telecommunications is to expand service providers’ views to show how they can systematically reduce energy consumption all along the energy path by such measures as:

• Implementing software upgrades that enable wireless service providers to turn off rectifiers when they are not needed. “Service providers are forced to over-engineer the number of rectifiers for the peak months,” Poulin said. Those peak months occur during the summer when, because of the rising temperature inside cabinets, rectifiers start cutting back on output capacity. “You have too much [power] on that site if I’m looking at it in January,” he said. “By applying energy management, I can cut off rectifiers in January or July, throttle them off in order to run the other ones at a peak efficiency point. That’s a fairly easy solution that suppliers can implement very quickly, either by enabling the function if it was provided or upgrading software inside their system.”
• Turning off transmitters or receivers at night, when usage goes down. “This can cut power consumption by half in the nighttime,” Poulin said. “It’s one of the fairly easy fixes.”
• Using DSL equipment in a CO that has an idle mode, so it also isn’t being powered at night, when most services aren’t being used. “When you stop using your equipment, power drops by significant amounts,” Poulin said.
• Modifying radio sites to move radio frequency (RF) converters and power amplifiers to the tops of radio towers. This is a more complex issue, Poulin said, because it requires new housing and major modification to the way radio base stations are built. Today, the RF converters and amplifiers sit at the base of the tower, and the signals are then run through a coaxial feeder cable to the top of the tower. “Half of that power gets lost from the bottom to the top, so producing that energy is an extremely inefficient process,” Poulin said.
• Using passive cooling for base stations in places where the weather is moderate.
• In the CO environment, running servers and storage devices on DC power, like traditional telecom gear. “Today, they have to use a converter, which means a lot of losses,” Poulin said. “This is not a data center, but you do have servers and storage equipment providing network support functions. We’ve identified that if you are powering with an inverter, you will save up to 5 kilowatts in conversion losses.”
• Cooling equipment within a CO also has become an inefficient process as more heat-generating equipment is added. As different types of broadband equipment have been added to the CO, service providers may have gotten away from cooling best practices and thus could be overspending on air conditioning, Poulin said. Containing hot air in ducts, making sure the hottest air is returned to the cooling unit directly and reducing humidity by isolating equipment rooms with vapor seals are among the ways to reduce the cost of air conditioning, which represents 40% of CO power costs.

The full Energy Logic for Telecommunications plan is explained in a white paper on Emerson’ Web site at www.emersonnetworkpower.com/energysystems/EnergyLogic.asp.

Previously: Part One of this series looked at AT&T’s green initiatives, while Part Two reported on Callis Communications’ effort to reduce power used by voice-over-IP gear. Part Three reported on iControl’s efforts to help service providers leverage home security system sales to also promote home automation and energy savings. Part Four explored new technology from Telco Systems to use solar power for data centers.