Green IT Factsheet

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Green Information Technologies (Green IT) reduce the environmental impacts associated with conventional Information Technologies (IT). Examples of Green IT include energy efficient hardware and data centers, server virtualization, and monitoring systems. Green IT focuses on mitigating the material and energy burdens associated with conventional IT while meeting our information and communication demands.1

Patterns of Use

  • 2.28 billion mobile phones, tablets, and PCs were shipped in 2017.4
  • Globally, more people have mobile phones than access to safe sanitation.5,6
  • 139 million smartphones were sold globally in 2008. Over 1.5 billion were sold in 2018.7
  • In 2016, 89% of households in the U.S. had a computer at home, compared to 8% in 1984. Of these households, 77% had a desktop or laptop, 76% had a smartphone, 58% had a tablet, and 81% had a broadband internet connection.8
  • More than 14% of households used their primary computer for 10+ hours per day in 2009.9
  • In 2013, U.S. data centers consumed 91 billion kWh of electricity—2.4% of total electricity consumption—at a cost of $13 billion.2,3
  • The peak power associated with servers and data centers in 2007 was 7 GW. Existing technologies and efficient design strategies can reduce server energy use by 25% or more, while best management practices and consolidating servers can reduce energy use by 20%.10
  • Computers and office equipment consumed 253 billion kWh of electricity in 2012, 24% of the total electricity consumption of office buildings that year.11

Energy and Environmental Impact

  • Electricity used for U.S. servers & data centers creates 103 billion lbs CO2e annually.2,13
  • Computer electricity consumption varies greatly with age, hardware, and user habits. An average desktop computer requires 48 W when idle and 2.3 W in sleep mode (285 kWh annually). Laptops require less power on average - 15 W when idle and 1.2 W in sleep mode (89 kWh annually).14
  • A 17” light emitting diode (LED) LCD monitor uses about 13 W while on, 0.4 W in standby, and about 0.3 W when off.15
  • Every kWh used by office equipment requires an additional 0.2-0.5 kWh of air conditioning.16
  • The life cycle energy burden of a typical computer used for 3 years is 4,222 kWh. Only 34% of a computer’s life cycle energy consumption occurs in the 3-year use phase. Production dominates life cycle energy use due to the high energy costs of semiconductors and short use phase.17
  • Manufacturing represents 60-85% of life cycle energy demand for a personal computer and 50-60% for mobile phones. Remanufacturing energy is a fraction of manufacturing energy: 5-30% for personal computers and 5% for mobile phones.18
  • Some emerging technologies can reduce manufacturing burdens. Globally, 3D printing has the potential to reduce total primary energy use by 2.5-9.3 EJ and CO2 emissions by 131-526 Mt by 2025.19

End use electricity Consumption of U.S. Data Centers2,3

Figure_1_Electricity Use by U.S. Data Centers, by End Use

Power Used by Office Equipment12

Power Used by Office Equipment

Electronic Waste

  • In 2016, approximately 45 million metric tons of e-waste were generated worldwide only 20% were recycled properly.21
  • U.S. federal hazardous waste regulations allow the export of e-waste, posing a global threat to human health.22,23 An estimated 5-30% of the 40 million computers used in the U.S. were exported to developing countries in 2010.24 In 2016, Basel Action Network found that 34% of the e-waste tracked by GPS trackers in the U.S. moved off shore, almost all to developing countries.25
  • In 2010, the U.S. disposed of 52 million computers and 152 million mobile devices. 40% of computers and 11% of mobile devices are recycled.26
  • The main constituents of printed circuit boards used in mobile electronics are polymers and copper, with trace amounts of precious metals Ag, Au, and Pd, and toxic metals As, Be, Cr and Pb.27
  • One ton of printed circuit boards has a higher concentration of precious metals than one ton of mined ore.28

Composition of a Desktop Computer20

Composition of a Desktop Computer

Paper Industry

  • Paper production increased by 2.5% from 2012-2016 globally, but decreased by 4% in Northern America.29 Annual consumption of printing and writing paper is expected to rise from 109 to 274 million metric tons between 2006 and 2060.30
  • The U.S. accounts for approximately 18% of global printing and writing paper consumption.29
  • Depending on the process, producing one ton of paper consumes 12 to 24 trees.31
  • In 2017, greenhouse gas emissions of the U.S. pulp and paper manufacturing industry were 35.8 million metric tons CO2e, approximately equivalent to the annual carbon sequestered by 44 million acres of US forests.32,33

Sustainable Alternatives


  • Virtualization enables one physical server to run many independent programs and/or operating systems.34 This technology reduces the number of physical servers needed and promotes greater utilization of each server. With virtualization, each machine can run at 80% capacity rather than 10%.35 Virtualization reduces cost, material waste, electricity use, server sprawl, and cooling loads, saving money while reducing the environmental burdens of running a data center.34
  • Data center energy efficiency can be improved by utilizing combined heat and power systems. Heat recovered from electricity generation in the form of steam or hot water can be used by an on-site chiller to cool the data center.36
  • Multi-function office equipment can reduce energy consumption and waste. To save money and energy, Energy Star recommends choosing a machine that combines multiple functions, like printing and scanning, instead of purchasing two different machines.37
  • Video teleconferences can greatly reduce business travel impacts. One study found that a video conference requires 500 times less energy than a business trip including a 1,000 km (663 miles) flight.38 Telecommuting, in which employees work in distributed locations, is increasing in frequency. One study found full-time telecommuting could prevent 3,700 lbs of CO2 emissions per employee per year.39

Reduce Energy Consumption

  • Office equipment energy consumption could be reduced by 23% if all office equipment had and utilized low-power mode. If all desktop computers and printers were turned off for the night, energy consumption would be further reduced by 9%.40 If every PC in the world were shut off for one night, the energy saved could light the Empire State Building for over 30 years.41
  • Energy Star certified computer servers are, on average, 30% more energy efficient than standard servers. Replacing a conventional server with an Energy Star server could save up to 1000 kWh annually. If all servers sold in the U.S. met Energy Star standards, $800 million per year would be saved in energy use.43
  • Energy consumed by devices in standby mode accounts for 5-10% of residential energy use, adding up to $100 per year for the average American household. Unplug electronic devices when not in use, or plug them into a power strip and turn the power strip off.44 Turning off a computer when it is not in use can save $50, 505 kWh, and 571 lbs of CO2 per computer annually.13,45
  • When leaving computers on, the EPA recommends setting computer monitors to go to sleep after 5-20 minutes of inactivity, and to enter standby after 15-60 minutes.46

Embodied Greenhouse Gas Emissions:Computing and Electronics Products42

Embodied Greenhouse Gas Emissions: Computing and Electronics Products

Take Action

  • Make informed purchases. Energy Star’s Excel-based calculators estimate energy and cost savings for office equipment, appliances, electronics, and lighting.47 The EPA’s Electronic Product Environmental Assessment Tool (EPEAT) rates the environmental impacts of computer products across multiple criteria, including energy efficiency, material toxicity, and recyclability.48
  • Purchase Energy Star certified products, consolidate multiple devices into all-in-one equipment, and turn off devices when not in use.49
  • The average American uses 430 pounds of paper each year, and 45% of printed paper in offices is discarded by the end of the day. Save resources by not printing or, when a paper version is necessary, by printing double-sided on recycled paper.50,51,52
  • Extend the life of personal computers to delay the energy and materials burdens associated with making new equipment.17
  • Recycle your unused electronics. Responsible Recycling Practices (R2) and e-Stewards offer third-party certification for electronics recyclers to ensure the proper disposal of used electronics.53
  1. Corbett, J. (2010) Unearthing the value of Green IT. ICIS Proceedings (2010): 1-21.
  2. Natural Resources Defense Council (2014) America’s Data Centers Are Wasting Huge Amounts of Energy.
  3. U.S. Energy Information Administration (EIA) (2016) Monthly Energy Review May 2016.
  4. Gartner (2018) “Gartner Says Worldwide Device Shipments Will Increase 2.1 Percent in 2018.”
  5. GSMA (2019) “The Mobile Economy”.
  6. World Health Organization (2019) Sanitation.
  7. Statista (2019) Smartphones in the US.
  8. U.S. Census Bureau (2018) Computer and Internet Use in the United States: 2016.
  9. U.S. EIA (2013) 2009 Residential Energy Consumption Survey.
  10. U.S. Environmental Protection Agency (EPA) Energy Star Program (2008) EPA Report to Congress on Server and Data Center Energy Efficiency Public Law 109-431.
  11. U.S. Department of Energy (DOE), EIA (2016) Commercial Buildings Energy Consumption Survey 2012.
  12. Menzes, A., et al. (2014) “Estimating the energy consumption and power demand of small office equipment.” Energy and Buildings, 75(2014): 199-209.
  13. U.S. EPA (2018) eGRID 2014 Summary Tables.
  14. Energy Star (2013) “Office Equipment Calculator.”
  15. Park, W., et al. (2013) Efficiency Improvement Opportunities for Personal Computers: Implications for Market Transformation Programs.
  16. Roth, K., et al. (2002) Energy consumption by office and telecommunications equipment in commercial buildings, Volume 1: Energy Consumption Baseline. U.S. Department of Commerce, National Technical Information Service.
  17. Keoleian, G. and D. Spitzley (2006) Life Cycle Based Sustainability Metrics. Sustainability Science and Engineering.
  18. Quariguasi-Frota-Neto et al. (2012) “An analysis of the eco-efficiency of remanufactured personal computers and mobile phones.” Production and Operations Management Society, 21(1): 101-114.
  19. Gebler, M., et al (2014) “A global sustainability perspective on 3D printing technologies.” Energy Policy, 74(2014): 158–167.
  20. U.S. EPA (2016) Documentation for Greenhouse Gas Emissions and Energy Factors Used in the Waste Reduction Model.
  21. United Nations University (2017) The Global E-Waste Monitor 2017.
  22. U.S. EPA (2017) Final Rule: Hazardous Waste Export-Import Revisions.
  23. Graham Sustainability Institute (2017) “E-waste recycling.”
  24. Kahhat, R. and E. Williams (2012) “Materials flow analysis of e-waste: Domestic flows and exports of used computers from the United States” Resources, Conservation and Recycling, 67: 67-74.
  25. Basel Action Network (2016) Scam Recycling: e-Dumping on Asia by U.S. Recyclers.
  26. Electronics Take Back Coalition (2014) Facts and Figures on E-Waste and Recycling.
  27. Holgersson, S., et al. (2016) “Analysis of the metal content of small-size Waste Electric and Electronic Equipment (WEEE) printed circuit boards—part 1: Internetrouters, mobile phones and smartphones.” Resources, Conservation and Recycling (2017): 1-9.
  28. Betts, K. (2008) Producing usable materials from e-waste. Environmental Science & Technology.
  29. Food and Agriculture Organization of the United Nations (FAO) (2017) Global Forest Products Facts and Figures 2016.
  30. Buongiorno, J., et al. (2012) Outlook to 2060 for World Forests and Forest Industries: A Technical Document Supporting the Forest Service 2010 RPA Assessment.
  31. Conservatree (2012) “Trees into Paper.”
  32. U.S. EPA (2019) Greenhouse Gas Reporting Program Pulp and Paper
  33. U.S. EPA (2019) “Greenhouse Gas Equivalencies Calculator.”
  34. Energy Star (2013) “Server Virtualization.”
  35. Ruest, N. and D. Ruest (2009) Virtualization, A Beginner’s Guide. McGraw-Hill Osborne Media.
  36. U.S. EPA (2008) The Role of Distributed Generation and Combined Heat and Power Systems in Data Centers.
  37. Energy Star (2012) “Choose Energy Star certified office equipment.”
  38. Toffel, M. and A. Horvath (2004) Environmental Implications of Wireless Technologies: News Delivery and Business Meetings. Environmental Science and Technology, 38(11): 2961-71.
  39. Roth, K., et al. (2008) The Energy and Greenhouse Gas Emission Impacts of Telecommuting in the U.S.
  40. Kawamoto, K., et al. (2001) Electricity used by office equipment and network equipment in the U.S.: Detailed report and appendices. U.S. DOE, LBNL.
  41. Alliance to Save Energy (2009) PC Energy Report, United States, United Kingdom, Germany.
  42. Teehan, P. and M. Kandlikar (2013) Comparing Embodied Greenhouse Gas Emissions of Modern Computing and Electronics Products. Environmental Science and Technology, 2013, 47, 3997−4003.
  43. Energy Star (2018) “Enterprise Servers.”
  44. U.S. DOE (2012) “3 Easy Tips to Reduce Your Standby Power Loads.”
  45. Bray, M. (2008) Review of Computer Energy Consumption and Potential Savings.
  46. Energy Star (2013) “Computer Power Management Savings Calculator.”
  47. “Energy Star (2017) Purchase energy-saving products.”
  48. EPEAT (2012) Choosing the Right Electronics Infographic.
  49. U.S. DOE, Lawrence Berkeley National Laboratory (2013) “Home Energy Saver: Home Office Equipment.”U.S. EPA (2013) “Certification Programs for Electronics Recyclers.”
  50. U.S. EPA (2016) Advancing Sustainable Materials Management: Facts and Figures 2014.
  51. U.S. Census Bureau (2018) Population Clock.
  52. Environmental Paper Network (2008) Increasing Paper Efficiency.
  53. U.S. EPA (2013) “Certification Programs for Electronics Recyclers.”
Cite as: 
Center for Sustainable Systems, University of Michigan. 2019. "Green IT Factsheet." Pub. No. CSS09-07.