Environmental Energy Technologies Internetdatatalk ppt Electricity used by the Internet: How an urban legend has become conventional wisdom Jonathan Koomey, Ph.D. Lawrence Berkeley National Laboratory 510/ , For more details on the analysis discussed here, go to or Download: Presented at the U.S. Telecom Association Conference Dallas, Texas May 22, 2001

Environmental Energy Technologies Internetdatatalk ppt Beware false premises The fascinating impressiveness of rigorous mathematical analysis, with its atmosphere of precision and elegance, should not blind us to the defects of the premises that condition the whole process. There is perhaps no beguilement more insidious and dangerous than an elaborate and elegant mathematical process built upon unfortified premises. --T. C. Chamberlain, late 1800s-- 21st century translation: Garbage in, Garbage out

Environmental Energy Technologies Internetdatatalk ppt Background  The Internet Begins with Coal, by Mark Mills, was published in Forbes in May  Results were widely cited and have become conventional wisdom.  Memo to EPA dated 9 December 1999 was our initial response  Congressional testimony given by Mills, Jay Hakes, and Joe Romm on 2 February 2000.

Environmental Energy Technologies Internetdatatalk ppt Background (continued)  Koomey rebuttal to Mills testimony completed in August  Our comprehensive analysis of office equipment electricity use presented in August 2000, and full documentation completed in February  Mills’ claims are becoming less widely believed, but many people still cite them.

Environmental Energy Technologies Internetdatatalk ppt Mills’ analysis was flawed  Bad data: 1-2 kW PCs, 500 kW central offices, 250 kW mainframes, 1 kW routers in LANs.  Bad boundary definitions: Just what part of a PC or a server is “associated with the internet”, anyway?  Overlooked systemic effects: information tech. can affect the efficiency of many processes.

Environmental Energy Technologies Internetdatatalk ppt Mills’ electricity “used by the internet”, corrected by LBNL TWh per year

Environmental Energy Technologies Internetdatatalk ppt Data needs  Equipment sales  Power use (W) by operating mode  Usage (Hours) by operating modes  Equipment stocks (estimate using sales and lifetimes, and/or assess using surveys)  Materials use, reuse, and recycling  Estimate energy use and emissions  Systemic effects (e.g., telecommuting, e- commerce)

Environmental Energy Technologies Internetdatatalk ppt Latest estimate of office equipment electricity use by sector in 1999 Residential 12% Industrial 13% Network 4% Commercial 71% Total = 74 TWh

Environmental Energy Technologies Internetdatatalk ppt Comparison of Estimates of Energy Use for Commercial Office Equipment in 1999 Printer Desktop/Portable/Server Computer Display/Terminal Mainframe/Minicomputer Copier/Fax Annual Energy Use (TWh)

Environmental Energy Technologies Internetdatatalk ppt A key uncertainty: Data centers/server hotels  Some utilities receiving requests for tens to hundreds of MW of power from proposed data centers  Estimates for power use almost certainly too large — One facility maximum = 90 W/sf, actual <40W/sf. — Another facility claimed 65 W/sf, but floor area defined incorrectly to exclude aisles and other common areas, leading to an overestimate of power use (this definition is critical) — Still another facility took direct server load and multiplied by three (!) to account for cooling, lighting, and other uses (implies a COP of about 0.5, 3-4 times too low)

Environmental Energy Technologies Internetdatatalk ppt Upper bound estimate to electricity used by data centers in the U.S (1) Floor area taken from Juarez, Richard A Virtual Bricks II: Virtual Econ 101 Update: A Comprehensive Guide for Understanding eCommerce Infrastructure Evolution and Convergence. Boston, MA: FleetBoston Robertson Stephens Inc. May. There is big uncertainty in the floor area number (could be as much as a factor of two too high). (2) Power density is an upper bound based on recent discussions with experts. Ignores the possibility that server loads are shifted from existing installations and not new loads. (3) Electricity use calculated assuming 8760 hours per year operation, flat load curve. (4) Total U.S. electricity use taken from EIA’s Annual Energy Outlook Contact: 510/

Environmental Energy Technologies Internetdatatalk ppt Possible systemic effects of information technology (IT)  Commercial floor space — Reduced office space — Reduced warehouse space  Changes in travel patterns  More efficient use of energy and materials  IT + utility deregulation = energy service markets for big service providers

Environmental Energy Technologies Internetdatatalk ppt Something unusual may be going on Source: Joe Romm, Center for Energy and Climate Solutions

Environmental Energy Technologies Internetdatatalk ppt Conclusions  Misinformation seems to spread more quickly than truth.  Computers are NOT the cause of the California power crisis.  Electricity used by computers and network equipment, including telecommunications and manufacturing energy = 3% of U.S. electricity use U.S., not 13% as Mills implies.

Environmental Energy Technologies Internetdatatalk ppt Conclusions (continued)  Understanding the systemic effects of information technology is critically important.  Credible data are urgently needed.

Environmental Energy Technologies Internetdatatalk ppt Join the network for energy, environment, efficiency, and the information economy (N4E)

Environmental Energy Technologies Internetdatatalk ppt If you really want to get the numbers right