Dirty Data?

Are e-mail attachments bad for the environment? Data-storage expert Matthew Yeager thinks so. In an interview with Mother Jones, Yeager compares the greenhouse gases created from sending a 4.7 megabyte-sized email attachment to boiling a kettle of water 17.5 times. As we inch over the one zettabyte marker of stored data worldwide, that’s — well, a whole lot of kettles. Yeager argues that redundancy represents a huge share of stored data, something to consider before sending that cute bunny photo to 300 of your closest friends. [%comments]

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  1. Ronaldo Yamashita says:

    A couple weeks ago I got the same question, did some back of the envelope calculations (got a power consumption of at least a city of 350,000 habitants).
    But after all, I concluded that if we did not have attachments, we would send far more physical copies, requiring gas for trucks and airplanes. It would be far worse for the environment.
    Also, some new technologies, like deduplication, will help to reduce environmental costs overtime.

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  2. David L says:

    The good news is that as data transfer gets faster and high-speed connectivity becomes more ubiquitous, it becomes less important for us to store data locally. Cloud infrastructure and SaaS, right now, are sort of just trendy buzzwords, but in a future world connected by fiber optics and high-speed mobile data networks, remote data storage could portend some major synergies.

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  3. Ian Kemmish says:

    I notice he doesn’t actually produce evidence for that figure, but it seems very high. Let’s apply the principles of “street math” you espoused a few weeks ago.

    My iMac takes a fraction of a second on just one core to send that file. My ISP’s servers presumably take even less. Lets say the email goes through ten computers on its way to the recipient. That’s still (a lot) less than a second of CPU time, but less be generous and call it a second. At maybe 100 watts, that’s 1/36,000 kWh. My modem is tied up for a minute or two uploading the data, but I haven’t switched it on specially, so that’s a fraction of a watt (busy vs. idle consumption) for a minute – still not much. 1/120,000 kWh? Adding a generous fudge factor for all those routers out there, lets say a total of maybe 1/20,000 kWh

    Boiling a kettle is 3kW for maybe three minutes. I make that 3/20 kWh. The electricity it takes to boil one kettle would appear to be equal to the marginal electricity use of sending three thousand (give or take) such emails.

    Of course, there’s the amortised energy cost of actually building and shipping my iMac, but how much is that likely to be for just one email?

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  4. Ian Mason says:

    These figures are ridiculous; I can see that some people failed their physics exams.

    Let’s examine the claim:

    “sending an email attachment of 4.7 megabytes-the equivalent of about 4 photos
    taken on a point-and-shoot digital camera-creates as much greenhouse gas as
    boiling your tea kettle 17.5 times”

    OK. A standard jug kettle contains 2 litres of water. Water has a specific
    heat capacity of 4.2 kJ/KgK, comes out of the tap at circa 10 degrees C and boils
    at 100 degrees C. So boiling one kettle full of water consumes:

    4.2 kJ/KgK * 2 Kg * 90 K = 756,000 J (Joules of energy)

    17.5 times that is 13,230,000 joules, or 13.230 megajoules (MJ). One kilowatt hour
    of electricity (energy) is 3.6 Megajoules, so we’re talking about a claimed
    3.675 kilowatt-hours to send one email. That’s more energy than required to run
    a 3 bar electric fire for an hour.

    So, the claim is that one 4.7 megabyte email takes 13.25 megajoules, that’s
    2.8 joules per byte!

    To demonstrate how farcically wrong Yeager must be I’ll point out that the muzzle
    energy of a 5.56mm rifle bullet is 1780 joules, so by Yeager’s claim a email
    attachment of a mere 636 bytes embodies as much energy as a rifle bullet. Or
    let’s compare it to the iconic Hiroshima atom bomb, which released about 63
    terajoules. Yeager’s figures would make Hiroshima equivalent to 4.7 million
    email attachments of 4.7 megabytes.

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    • jackie says:

      It’s not about how much immediate energy is used to download the data, it’s about how much electricity is used to run the servers that INDEFINITELY store your data. When’s the last time you cleaned out your email inbox? Yahoo, Google, Hotmail, etc – they all use massive amounts of energy to run their data storage servers. So how much electricity does a computer take? Not much over a few seconds – but over decades, we’ve got a serious problem on our hands.

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      • jackie says:

        …and on another note, we’re not talking about mailing a document VS email attachment. We’re talking about uploading it to a central source, such as Facebook or Youtube, then just share the LINK with your friends, instead of duplicating the actual document file 20+ times.

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  5. Albert Alexander says:

    If you try to save the world by reducing clock cycles, you will get nowhere. Your picture of a cat pales in comparison to spam, bittorrent, porn, radio, TV, and cell phones. Or how about the “cost” of rendering a first-person shooter game at 60 fps for 20 hours a week?

    If you’re dying to make a difference, you could send all your email at night. During off-peak hours, power companies burn off megawatts, simply because its cheaper than turning off the factory. You’re doing them a favor by consuming that power for a purpose.

    Or hell, you could do ‘em one better. Get a local fileserver to handle all your local friends’ email. Spin up a big ol’ flywheel all night and use it to power the server during the day.

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  6. Jason Morris says:

    While I agree with the other comments that the statistics supporting this assumption are completely absurd.

    Secondly (and far more importantly,) even if the numbers made sense, the fundamental argument is ridiculous:

    Claiming that emails with large attachments hurt the environment is equivalent to claiming that ‘building solar panels hurts the environment because of the resource intensive, high cost materials used during construction.’

    Yes. Making and storing things (even data) requires resources and energy. But the message behind those annoying little reminds at the bottom of emails (“Think Green! Please consider the environment before printing this email!”) are still far more important. The result of NOT sending that email with a large attachment are far more harmful than the environmental damage caused by the email.

    With a blog title “Freakonomics” you’d think you would have heard of opportunity costs before.

    Please go back to economics 101, you’re hack-environmentalism is embarrassing.

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  7. Erik says:

    Others have dealt with some of the absurdity of this. I’ll tack on another point:

    “Yeager compares the greenhouse gases created from sending a 4.7 megabyte-sized email attachment to boiling a kettle of water 17.5 times.”

    Really? The inputs are know to three figures of precision? That’s surprising, given that he doesn’t even talk about the volume of the kettle.

    Also, what is meant by “created?” There’s a big difference between marginal costs and average total costs.

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  8. Jay says:

    I don’t think it is the transmission of the file where the energy use is–it is the storage of data. Someone has to pay to house that file for the next 100 years because chances are it is not going to be deleted.

    The bigger point is that externalities are usually difficult to see and measure.

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