Research carried out by Mobile PBX company, OnRelay, showed that 25 million IP desk phones projected to be purchased in 2008 consume 1.6 billion Watts of power.
This is equivalent to the needs of a 300,000 person UK city, which is more than Oxford and Cambridge, combined.
Obviously, not all of those are left idle or redundant but there could be some massive energy savings should companies ditch desktop based phones and replace them by mobile phone solutions.
Replacing the majority of IP desk phones with mobile phones could yield a 74% savings in power consumption by telephony equipment can be achieved.
Telephony equipment is one of the biggest heat sources in the data center according to OnRelay and Just to cool and run telephony equipment for a 10,000 person company would requires 640 kW of power, costing nearly £600,000 at current electricity prices.
And according to a recent Gartner report, 70 percent of CIO's are reporting that power and/or cooling issues are now their single largest problem in data centers.