Energy and emissions for one search, including the figures at the centre of the 2009 row. Each entry records the claim as published: what it counts, who made it and who paid,
and any dispute. Figures with different boundaries are not comparable without reading what each counts.
Google search including the user's PC, John Buckley's estimate in The Sunday Times
1 to 10 g CO2 per Google search
A separate estimate from John Buckley, managing director of carbonfootprint.com , a British environmental consultancy, puts the CO2 emissions of a Google search at between 1g and 10g, depending on whether you have to start your PC or not. Simply running a PC generates between 40g and 80g per hour, he says.
the user's PC (the range depends on whether the PC has to be started)
Leaves out
not stated
Model or version
not stated
Place
not stated
Period measured
not stated
Method
not stated
Claimed by
Independent: John Buckley (carbonfootprint.com), quoted by The Sunday Times
Paid for by
not stated
Dispute
none
History
Added.
Google search with 15 minutes of computer use, Chris Goodall's estimate in The Sunday Times
7 to 10 g CO2 per Google search (assuming 15 minutes’ computer use)
Chris Goodall, author of Ten Technologies to Save the Planet, estimates the carbon emissions of a Google search at 7g to 10g (assuming 15 minutes’ computer use).
A Google search, assuming 15 minutes’ computer use
Scope
end to end
Counts
15 minutes’ computer use
Leaves out
not stated
Model or version
not stated
Place
not stated
Period measured
not stated
Method
not stated (the article says "carbon emissions"; recorded as gCO2 because the article reports the other estimates as CO2)
Claimed by
Independent: Chris Goodall, quoted by The Sunday Times
Paid for by
not stated
Dispute
none
History
Added.
Average Google search, Google's 2009 figure
a mean of 0.3 Wh per Google search (published as: 0.0003 kWh of energy per search, or 1 kJ (converted from kWh to Wh))
0.2 g CO2 per Google search
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. ... In terms of greenhouse gases, one Google search is equivalent to about 0.2 grams of CO2.
the servers that work on the query; other work performed before the search starts, such as building the search index
Leaves out
not stated
Model or version
not stated
Place
not stated
Period measured
not stated
Method
not stated
Claimed by
Company: Google (Urs Hölzle, Senior Vice President, Operations)
Paid for by
none
Dispute
none
The calculator uses this figure: Web search (Google's 2009 estimate).
History
Added.
Typical Google search, as reported by The Sunday Times ("two searches boil a kettle")
7 g CO2 per Google search
Status: corrected.
Physicist Alex Wissner-Gross says that performing two Google searches uses up as much energy as boiling the kettle for a cup of tea ... 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.
not stated (the body attributes the figure to "new research"; the standfirst attributes the kettle comparison to Alex Wissner-Gross)
Claimed by
Independent: The Sunday Times (Jonathan Leake and Richard Woods)
Paid for by
none
Dispute
Google's official blog (11 January 2009) said the claim that a typical search produces 7 grams of CO2 is many times too high, and gave about 0.2 g CO2 per search (https://googleblog.blogspot.com/2009/01/powering-google-search.html). Alex Wissner-Gross told TechNewsWorld that his work had nothing to do with Google and that the kettle comparison was the newspaper's, not his (https://web.archive.org/web/20091217121803/http://www.technewsworld.com/story/Harvard-Prof-Sets-Record-Straight-on-Internet-Carbon-Study-65794.html). On 16 January 2009 The Sunday Times added a clarification: the 7 g does not refer to a one-hit search taking less than a second, for which it accepts Google's figure of about 0.2 g, but to a search that may involve several attempts and last several minutes, for which experts gave 1 g to 10 g (https://web.archive.org/web/20090729054637/http://technology.timesonline.co.uk/tol/news/tech_and_web/article5489134.ece).
History
Added.
Typical Google search, as stated by the IEA in Electricity 2024
a mean of 0.3 Wh per Google search
When comparing the average electricity demand of a typical Google search (0.3 Wh of electricity) to OpenAI's ChatGPT (2.9 Wh per request), and considering 9 billion searches daily, this would require almost 10 TWh of additional electricity in a year.
A typical Google search, compared with a ChatGPT request (2.9 Wh)
Scope
not stated
Counts
not stated
Leaves out
not stated
Model or version
not stated
Place
not stated
Period measured
not stated
Method
not stated (page 34 gives no source for the 0.3 Wh figure; the source notes for the nearby data centre charts cite de Vries, "The growing energy footprint of artificial intelligence", Joule, 2023)