Where Does All the Computer Power Go?

Report to Congress on Server and Data Center Energy Efficiency; public Law 109-431
U.S. Environmental Protection Agency ENERGY STAR Program, August 2, 2007. (PDF, 133 pages.)


"The energy used by the nation’s servers and data centers is significant. It is estimated that this sector consumed about 61 billion kilowatt-hours (kWh) in 2006 (1.5 percent of total U.S. electricity consumption) for a total electricity cost of about $4.5 billion. This estimated level of electricity consumption is more than the electricity consumed by the nation’s color televisions and similar to the amount of electricity consumed by approximately 5.8 million average U.S. households (or about five percent of the total U.S. housing stock). Federal servers and data centers alone account for approximately 6 billion kWh (10 percent) of this electricity use, for a total electricity cost of about $450 million annually.

"The energy use of the nation’s servers and data centers in 2006 is estimated to be more than double the electricity that was consumed for this purpose in 2000. One type of server, the volume server, was responsible for the majority (68 percent) of the electricity consumed by IT equipment in data centers in 2006. The energy used by this type of server more than doubled from 2000 to 2006, which was the largest increase among different types of servers. The power and cooling infrastructure that supports IT equipment in data centers also uses significant energy, accounting for 50 percent of the total consumption of data centers. Among the different types of data centers, more than one-third (38 percent) of electricity use is attributable to the nation’s largest (i.e., enterprise-class) and most rapidly growing data centers......

"Under current efficiency trends, national energy consumption by servers and data centers could nearly double again in another five years (i.e., by 2011) to more than 100 billion kWh (Figure ES-1), representing a $7.4 billion annual electricity cost. The peak load on the power grid from these servers and data centers is currently estimated to be approximately 7 gigawatts (GW), equivalent to the output of about 15 baseload power plants. If current trends continue, this demand would rise to 12 GW by 2011, which would require an additional 10 power plants.

"These forecasts indicate that unless energy efficiency is improved beyond current trends, the federal government’s electricity cost for servers and data centers could be nearly $740 million annually by 2011, with a peak load of approximately 1.2 GW."