Yesterday, while slaving over a hot keyboard, this blogger praised the e-magazine/e-newspaper innovation. The belief that online publications are more environmentally friendly remains unshaken. However, today's Salon offers their version of "Mr. Wizard" in "Ask Pablo." This new science popularizer, in an online publication, doesn't quite get at the burning question raised yesterday in this blog, but Pablo makes a strong case for e-documents. If this is (fair & balanced) vicissitude, so be it.
[x Salon]
Ask Pablo: Does Reading Online Uses More Energy Than Printing Documents...?
By Pablo Päster
Dear Pablo,
My parents are from the typewriter generation and insist on printing every document before they read it. Their argument is that reading it on the computer uses more energy than printing it out and turning the computer off. Is this true?
It certainly depends on the document and how you print it. A one-line e-mail would not make sense to print, where a 100-page reference document that is printed double-sided may make more sense to print. But let's try to back that up with some numbers.
My laptop uses about 30 watts (more during start-up). In the time it takes to read a page (8.5 x 11), let's say two minutes, the computer will use 0.001 kWh (kilowatt-hours) of electricity. For a 100-page document this adds up to 0.1 kWh of electricity, costing you less than 2 cents on your electricity bill. The generation of electricity creates about 1,000 pounds of greenhouse gases per MWh (megawatt-hour), or 1 pound per kWh, depending on where your electricity comes from. This means that reading a 100-page document on your laptop causes about one-tenth of a pound of greenhouse gas emissions. Pretty small. But how does that compare to paper?
The U.S. paper industry had emissions of 17.2 MmT (million metric tons) of CO2 in 1994, the most recent year that both numbers are available. In the same year, pulp and paper production in the U.S. was 59.05 MmT (million metric tons). Dividing these two numbers gives us the amount of CO2 per unit of paper: 0.29. This means that for every pound of paper, just under 0.3 pounds of GHGs are released. A 500-page ream of 20-pound paper weighs 20 pounds, so 100 pages weighs 4 pounds. If you print double-sided, you only need 50 pages, or 2 pounds of paper. Based on the numbers calculated above, 2 pounds of paper causes about 0.58 pounds of greenhouse gas emissions. And this doesn't even include the energy used by the printer or the computer during printing, which probably adds more than one-tenth of a pound.
So the contrast is quite convincing, one-tenth of a pound of greenhouse gas emissions from reading the document on the computer, versus almost three-quarters of a pound of greenhouse gas emissions for printing it out! So much for my guess that it may be better to print longer documents. Of course, there is always an exception. If you are going to read the document more than seven times, the greenhouse gas emissions for printing would be less than using the computer each time.
The advent of the computer came with promises of the paperless office but has, instead, resulted in an increase in the use of paper. Back in 1975, when computers were in their infancy, their impact was already being predicted. It was believed that the office of the future would be so efficiently digital that paper would become obsolete for bookkeeping and editing. The only problem was that the spread of digital printers and photocopiers made it so easy to produce documents that paper use proliferated. Only now are we getting comfortable enough with our technology that we can keep documents digital with no disadvantage to us. In fact, in some ways, reading a document on a computer can increase your personal comfort by decreasing eyestrain. New, flat-panel monitors no longer bake your eyes with radiation, the screen can be adjusted for brightness and you can increase the font size or zoom in to make reading easier.
One argument used to be that you have to print everything so that you have a hard copy in case the computer crashes. Today we have secure servers with backup power generators, fire-suppression technology and built-in encryption that can be accessed from anywhere with an Internet connection. After all, paper documents are not as safe as your digital ones. They can burn or be stolen, and, worst of all, can't be accessed by you from an Internet cafe in Barcelona.
[Pablo Päster earned a B.S. in Engingeering from the California Polytechnic State University-San Luis Obispo and an MBA at the Presidio School of Management. Päster is a VP at ClimateCHECK in San Francisco and a freelance writer at Salon. His column, "Ask Pablo," appears on alternate weeks in Salon.]
Copyright © 2008 Salon Media Group, Inc.
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Excellent, that was a valid calculation that rests the argument FOR using the laptop for reading as opposed to paper that for some reason has been taken for granted. I think the sum, although generalised, is accurate enough to argue the point conclusively. I may need to bookmark this and link later. Believe it or not I sell photocopiers but have an ironically protective view of the environment. Well done, Pablo! As an aside, would you be able to advise in your opinion the use of standby for best energy efficiency? Cheers :)
ReplyDeleteI hope that Jon knows that his query/aside should be sent to Pablo at Salon.com!
ReplyDeleteBest,
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