IFGICT Built Environment
Information Technology (IT) offers many benefits including increased productivity, access to information, and convenience. However, the production, use, and disposal of computers require large amounts of energy and resources. Green IT enhances the sustainability of computing through manufacturing lower impact materials and products, reduced energy consumption of data centers and computers, and better recycling and end of life management.
Patterns of Use
Electricity Use by U.S. Data Centers, by End Use1
Network Equipment, 5% • Data centers in the U.S. consumed 61 billion kWh of electricity in 2006—1.5% of total Storage Devices, 5% electricity ...view middle of the document...
S. servers & data centers.7 • Electricity consumption of computers varies greatly with age, hardware, and other factors. An average desktop computer uses 70W when active and 9W in low power mode. Laptops use significantly less energy—about 19W when active and 3W in low power mode.8 • A 17” cathode ray tube (CRT) monitor uses 61W when active, 2W in low power mode, and 1W when off. A 17” liquid crystal display (LCD) monitor uses 35W while on, 2W in low power mode, and 2W when off.8 • For every kilowatt hour used by office equipment, an additional 0.2-0.5 kWh load is placed on the air conditioning unit.9 • The annual life cycle burden of a computer is 5,600 MJ. Only 34% of life cycle energy consumption occurs in the use phase; extending the lifetime could mitigate the energy burden of the production and disposal phases.10
Active Low Power Off
100 150 Power (W) 200
Electronic Waste • Between 20-25 million tons of electronic waste (e-waste) are generated worldwide each year.12 • U.S. federal hazardous waste regulations do not deter exporting potentially hazardous e-waste, which is often handled and disposed of unsafely, threatening humans and the environment.13 One study estimated that 50-80% of e-waste collected for recycling in the U.S. is exported to developing countries, although a study by the U.S. International Trade Commission found that 17% of used electronic products were exported in 2011.14,15 • In 2009, the U.S. disposed of 29.4 million computers and 129 million mobile devices (phones, PDAs, pagers). About 40% of computers and 10% of mobile devices are recycled.16
Composition of a Desktop Computer 6
Aluminum, 14% Iron, 20% Copper, 7% Lead, 6% Zinc, 2% Nickel, 1% Tin, 1% Selenium, Manganese, Arsenic, Cadmium, 1%
Paper Industry • Global paper use increased 11% from 2000 to 2011.17 Annual consumption of printing and writing paper is projected to increase from 109 million metric tons in 2006 to 274 million metric tons in 2060.18 The U.S. accounts for approximately 18% of printing and writing paper consumption.17 • Depending on the production process, one ton of paper can take between 12 and 24 trees to produce.19 • The average annual greenhouse gas emissions of the U.S. pulp and paper manufacturing industry are 176 million metric tons CO2e, approximately equivalent to the annual emissions of 50 coal fired power plants.20,21 • One study comparing paper and digital journal articles found that life cycle energy consumption varied greatly depending on the number of times an article was read, the reader’s driving distance, and whether copies were printed. Generally, the study found the digital option saves energy when an article is read only a few times, and paper saves energy when an article is read many times.22
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Technology Life Cycle Impact of One Ton Uncoated Freesheet Paper41 • Virtualization...