1. Carnegie Mellon Electricity Impacts of Data Networks Carnegie Mellon University Green Design Initiative Francis McMichael - H. Scott Matthews Chris Hendrickson - Hui Min Chong Woon Sien Loh

2. Carnegie Mellon Issues Vast majority of energy consumed by Information and Communications Technology (ICT) is electricity in buildings (residential + commercial) Places burdens on businesses, consumers, and energy policymakers to manage demand –Reports estimate ICT electricity use as 3-5% of US total ICT has implications on other digital and built infrastructures –Data networks, highways, airspace, logistics –ICT has not ‘replaced’ these, it is ‘overlayed’ –And creates interdependencies between them

3. Carnegie Mellon Office Building ICT Use Sources: EIA CBECS (1992, 1999), Annual Energy Outlook 2002 [Commercial electricity projected to increase 1.7% per year, commercial ICT 4% per year] Anecdote: roughly 200 sq. ft of total commercial space per person! ICT electricity use in office buildings projected to increase a factor of 10 from 1992 levels, intensity a factor of 8 -> to 2% of all US electricity To reduce burden, further ‘green building’ programs needed to offset projected ICT electricity growth

4. Carnegie Mellon Focus on Networking Wired networks operate up to 100 or 1000 Megabits per second (Mbps) Wireless slower, but increasing in speed (soon to go from 5 to 55 Mbps) CMU campus: ubiquitous wired, wireless networks –Every room on campus ‘wired’, every space ‘wireless’ –10,000 users; 350 wireless antennas @ 30 users each –Functional, but not equivalent, comparison –Show energy “to network 10,000 users wired/wireless” –Only ‘network’ - not ‘attached devices’ - in boundary

5. Carnegie Mellon Campus Network Model 120 Wiring Closets Office/room equipment 350 Wireless Antennas Main computer center

6. Carnegie Mellon Two Data Sources Campus has building-level electricity meters installed –Several buildings have more than one meter when areas have higher than average use –Used for “Main computer center electricity” –Not so useful for electricity of room/equipment Portable power meters to measure electricity use of pieces of equipment –Measure one of each, scale up via inventory

7. Carnegie Mellon Metering SWAT Team -Pass-through device with LCD ($300) -Meter logs/outputs data, export into Excel

8. Carnegie Mellon Summary of Estimates

9. Carnegie Mellon Analysis Network electricity 6% of total campus - 1.7 kWh/ft 2 –In line with total office building ICT use in US Hard to compare to existing literature –A college campus not representative of overall demand, or even commercial buildings –Our particular campus much more ‘Wired’ than other campuses Wireless endpoints use 10 times less electricity than wired –Caveats: speeds, installation and maintenance requirements different –Wireless speed bump coming (10x) but electricity use expected go up only 50% –Relevance: more voice wireless than wired in the world

10. Carnegie Mellon Future ICT Scenarios Demand for data bandwidth and technology –Generally doubles every year (Odlyzko) Wireless: catching up with installed wired speeds –Also: allows deployment in harsh geographies, less-developed countries, new applications –Changing infrastructure needs of ‘cells’ (5 -> 0.01 km 2 ) Optical: currently have optical ‘glut’ –Both overbuilding, wavelength technologies Home networking (Voice-IP, DSL/cable, wireless) Distributed computing (i.e. idle cycle sharing)

11. Carnegie Mellon Conclusions ICT/elec growing rapidly, becoming more pervasive –Growing at a rate much higher than average –High economic value makes it an unlikely target Assessing ICT impacts requires knowledge and management of infrastructures ‘Systems analysis’ paradigm extended to digital infrastructures –LCA and other tools helpful in doing this

12. Carnegie Mellon Support Principal Investigator: –Organization of Economic Cooperation & Development (OECD) Environmental Policy Directorate (2000-02) –AT&T Corporation (1999-2002) –AT&T Foundation’s Industrial Ecology Faculty Fellowship Program (1999-2001) –US/Japan Foundation, United Nations (2001-2003) Other –NSF, EPA, DOE (w/LBNL) –Green Design Consortium