Ignore the media hype and keep Googling — The energy impact of web searches is very LOW

Some myths are hard to kill. The Times Online reports“:

Performing two Google searches from a desktop computer can generate about the same amount of carbon dioxide as boiling a kettle for a cup of tea, according to new research.

While millions of people tap into Google without considering the environment, a typical search generates about 7g of CO2 Boiling a kettle generates about 15g. “Google operates huge data centres around the world that consume a great deal of power,” said Alex Wissner-Gross, a Harvard University physicist whose research on the environmental impact of computing is due out soon.

The overhyping of the internet’s energy use goes back a decade, pushed by two right-wing deniers, Mark Mills and Peter Huber. They were actually using their easily-refuted analysis to argue against climate restrictions — I kid you not. In this 1999 press release from the laughably-named denier group, the “Greening Earth Society,” Mills says:

While many environmentalists want to substantially reduce coal use in making electricity, there is no chance of meeting future economically-driven and Internet-accelerated electric demand without retaining and expanding the coal component.

I ended up writing a major report debunking this myth and then testifying in front of the Senate Commerce committee (i.e. John McCain) and the House on the subject. Jon Koomey and others at Lawrence Berkeley National Laboratory (LBNL) did even more work debunking this nonsense (click here for everything you could possibly want to know on the subject).

There are actually two mistakes in the Harvard calculation. The first, which was the focus of my research, is the big picture issue. What is the net energy consumed by the internet? I argue the internet is a net energy saver — and a big one — since it increases efficiency (especially in things like the supply chain) and dematerialization (it uses less energy to research online than in person). The fact that U.S. energy intensity (energy consumed per dollar of GDP) began dropping sharply in the mid-1990s is but one piece of evidence that internet- and IT-driven growth is less energy intensive.

I, for instance, am able to work at home and telecommute thanks to the Internet and a broadband connection. That saves the energy consumed in commuting and a considerable amount of net building energy: Most people’s homes are an underutilized asset, which consume a great deal of energy whether or not they are there.

The other mistake just involves the more narrow question of how much energy is consumed by Googling. Wissner-Gross says it is 7g of CO2 per search. My LBNL colleagues say that is way too high, and Google itself has rebutted that analysis with their own, which I reprint here:

Not long ago, answering a query meant traveling to the reference desk of your local library. Today, search engines enable us to access immense quantities of useful information in an instant, without leaving home. Tools like email, online books and photos, and video chat all increase productivity while decreasing our reliance on car trips, pulp and paper.

But as computers become a bigger part of more people’s lives, information technology consumes an increasing amount of energy, and Google takes this impact seriously. That’s why we have designed and built the most energy efficient data centers in the world, which means the energy used per Google search is minimal. In fact, in the time it takes to do a Google search, your own personal computer will use more energy than Google uses to answer your query.

Recently, though, others have used much higher estimates, claiming that a typical search uses “half the energy as boiling a kettle of water” and produces 7 grams of CO2. We thought it would be helpful to explain why this number is *many* times too high. Google is fast — a typical search returns results in less than 0.2 seconds. Queries vary in degree of difficulty, but for the average query, the servers it touches each work on it for just a few thousandths of a second. Together with other work performed before your search even starts (such as building the search index) this amounts to 0.0003 kWh of energy per search, or 1 kJ. For comparison, the average adult needs about 8000 kJ a day of energy from food, so a Google search uses just about the same amount of energy that your body burns in ten seconds.

In terms of greenhouse gases, one Google search is equivalent to about 0.2 grams of CO2. The current EU standard for tailpipe emissions calls for 140 grams of CO2 per kilometer driven, but most cars don’t reach that level yet. Thus, the average car driven for one kilometer (0.6 miles for those in the U.S.) produces as many greenhouse gases as a thousand Google searches.

We’ve made great strides to reduce the energy used by our data centers, but we still want clean and affordable sources of electricity for the power that we do use. In 2008 our philanthropic arm,, invested $45 million in breakthrough clean energy technologies. And last summer, as part of our Renewable Energy Cheaper than Coal initiative (RE<C), we created an internal engineering group dedicated to exploring clean energy.

We’re also working with other members of the IT community to improve efficiency on a broader scale. In 2007 we co-founded the Climate Savers Computing Initiative, a group which champions more efficient computing. This non-profit consortium is committed to cutting the energy consumed by computers in half by 2010 — reducing global CO2 emissions by 54 million tons per year. That’s a lot of kettles of tea.

Bottom Line: Google, Youtube, blog, and flickr as much as you want. If you are worried about your carbon footprint, buy 100% green power and do an efficient retrofit on your house to cover your emissions — and let the Internet keep saving people energy and resources.

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13 Responses to Ignore the media hype and keep Googling — The energy impact of web searches is very LOW

  1. Zed says:

    Not to mention Google’s main office and data center is powered 30% by solar panels.

  2. paulm says:

    It is pleasing to see Direct Climate Change Action Now happening…this problem is not going to be address fully without it.

    Celebrities buy Heathrow land to delay third runway
    At full capacity, an expanded Heathrow would become the biggest single source of C02 emissions in the country. It would emit nearly 27m tonnes of CO2 every year – equivalent to the emissions of 57 of the least polluting countries in the world combined.

  3. Mark Shapiro says:

    Zed said: ” . . .Google’s main office and data center is powered 30% by solar panels.”

    Now if Google could only configure PV, which produces DC, to power their servers, which consume DC, directly, without first inverting to AC and then back to DC in the power supplies.

    Imagine powering a datacenter with PV, supplemented with fuel cells, which also happen to produce DC. (UTC sells 200 KW fuel cells, which invert the DC to AC. Strip out the inverter and power the servers directly with the DC output. And if you can use the waste heat to air condition the datacenter, you save even more.

    PV and fuel cells produce DC. All electronics (and LED lighting) use DC. Match made in heaven?

    Hmmm. Sounds like I’m back on my “DC standard” hobby horse. Oh well.

  4. dwight says:

    coincidentally the Green Lantern at Slate wrote about the carbon impact of blogging today and came to a similar conclusion. The article can be found here:

    I hope this is really a coincidence and not a response to some widespread conspiracy to undermine us from using the internet to save the planet.

  5. ET says:

    Once upon a time, when we were all scared about Global Warming, this might have been an issue.
    Now that the Global Warming theory is out and the Ice Age Cometh theory is in, it is surely good news that we can keep our homes warm by Googling our fingers off.
    And guaranteed to send Google shares sizzling :-)

    see ya
    ET – Just Thinking

  6. Brendan says:

    Something is bizarre with their numbers.

    ” In fact, in the time it takes to do a Google search, your own personal computer will use more energy than Google uses to answer your query. ”

    My laptop is probably around 80 W. We’ll say the “you” has a really power intensive computer at 300W.

    “a typical search returns results in less than 0.2 seconds. ”

    So, 300 W * 0.2 s = 60 J.

    60 J is way less than the 1 kJ they estimate. Am I missing something?

    1 kJ seems like an awfully high number, but I guess it makes sense. Based on a quick search google gets about 91 million searches an hour, or about 1000 per second. I could believe google uses a megawatt of power. I wonder why they put in that line about computer power.

  7. Barry says:

    Thanks as always Joe. I can’t tell you how many people sent the google=7g to me. It will be great to send this back.

    Reminds me of the “Prius is worse for climate than Hummer” viral scam awhile back.

  8. Joe says:

    if we all would skip every fifth breath we take( for when we breathe we make co2 more concentrated in our atmosphere) we could remove 5 trillion tonnes(euro spelling) of co2 from the air. also on the plus side that may kill the weaker of us saving even more co2. we must remember to sequester the bodies lest during decomposition they release all the carbon they themselves have sequestered these many years of their lives. i do feel bad making this suggestion as each letter i type adds a small fart of co2 to our already boiling world. please, no complaints from you sissies living back east. It is quite clear that the temporary cold that you are experiencing now was caused by people googleing global warming. if we all just not work together( as work makes C02) then we could set the thermostat of the world at a balmy 68 degrees and all would be happy. now, stop reading this as you are causing climate change ( the artist formerly know as global warming) right now. i mean it, stop! Are you still there? i can feel the heat even now. go away! aaaaeeeeee ouch ouch ouch :_(

    ps the use of capitols in this response has been eliminated. if we all just use lower case letter we could offset the carbon generated by one flight of algores jets across the country. this should be sufficient to guide your actions henceforth.

  9. Scatter says:

    Oops, didn’t spot the most recent post.

  10. Alex says:

    Joe (1:16 PM), at least learn something about the carbon cycle, and how much NET CO2 human breath contributes, before you post foolish comments on blogs. Thanks.

  11. The real problem with googling is that it gets wrong answers. How much energy is wasted in jawbone operation because of wrong answers?

    Reference: “Google and the myth of universal knowledge” by Jean-Noel Jeanneney 2007 The original is in French.

    When you do a Google search, you get “sponsored” links on the right side and “non-sponsored” links on the left. The “NON-SPONSORED” links on Google ARE LISTED IN THE ORDER OF THE HIGHEST BIDDER to lowest bidder. Companies pay dollars to Google to get web sites other than their own that lie in favor of the paying company to be at the top of the “non-sponsored” list. Google search results in your getting nothing but corporate propaganda. Since the coal industry has a $100 Billion per year income at stake, they can and must share a lot of money with Google.

    Page 32: 62% of internet users questioned make no distinction whatever between advertising and other information, and only 18% proved capable of telling which data were paid for by companies for their promotion and which were not.”
    “92% of users of search engines have full confidence in the results of their search, and 71% (users for less than five years) consider that information from this source [Google] is never biased in any way.”

    Suggestion: Use only Google Advanced or Google Scholar. On Google Advanced, specify either the .gov domain or the .edu domain. Otherwise, use only web sites that uses or the IPCC.

    George W. Bush messed up as many government web sites as he could get away with, but your chances are still clearly better than going to the richest propagandist .com or .org.
    Better yet: Get a degree in science so that you can figure it out for yourself.

    There should be a law requiring Google to disclose the above and the donors and the dollars for each “non-sponsored” link. Environmentalists should work on Google legislation first.

  12. Evan Mills says:

    Evan Mills and Jon Koomey provide more analysis here: