Department of Commerce

A way to realize $300M energy savings for desktop computers

Desktop computers at sleep mode can be woken up in seconds and only use less than 5 Watts of electricity compared to 100-200 Watts of consumption at regular mode. The energy savings can be well over 500 kWh per year for each desktop computer by enabling it to sleep when not in use, in particular at night. Now let us do a saving estimation from the electric bill only. Suppose there are 2.8 million desktop computers enabled by sleep mode (estimation based on the March 2009 federal government civilian employment data and assumes each employee uses one desktop computer) and the cost of 1kWh electricity is $0.2. The total savings from electric bill would be about $300 Millions per year ($0.2x500x2.8M). Furthermore, there will be additional savings in the computer maintenance and air-conditioning cost by enabling desktop computers to sleep. Although the potential savings from the application of sleep mode can be significant, this power option is rarely adopted by federal IT departments mainly due to the following reason. The sleep mode of a computer will prevent the automatic update of software, which is often very time consuming and could affect the normal usage of a computer. That is why the automatic update is mainly conducted at night and computers have to be on all the time. One of the promising solutions to this dilemma is Wake-on-LAN technique, which can remotely activate a sleeping computer by sending a series of specific codes through the network. In this way, sleep mode can be enabled by default after certain amount of no usage time in most of the desktop computers at the government. Wake-on-LAN is a feature already available on most of the desktop computers. So no further hardware investment is needed to realize this saving. Finally, not only will it save significantly for the government, but also will reduce the carbon emission into the environment.



Idea No. 13815