Analysis Assertions by a Harvard University environmentalist and green-website promoter that two Google searches cause carbon emissions equivalent to boiling a kettle appear to be based on questionable numbers. Building on the new research, the Reg can also exclusively reveal that three days of normal human farts cause the same amount of damage to the planet as a Google search. Google, however, say that a use of their search engine is only equivalent to farting once.
Alex Wissner-Gross, Environmental Fellow at Harvard University and CTO of co2stats.com ("makes your website carbon neutral") has made headlines round the world this weekend with his "two Googles = one kettle boil" calculation.
Wissner-Gross reckons a normal kettle boil results in 15 grams of CO2 emissions. Does that stand up?
Well, most people use a figure of 500 gCO2 per kilowatt-hour of electricity or thereabouts. (The UK wind industry recently agreed to come down to 460 after a row over misleading advertising, acknowledging that electricity is greener than its used to be, but we'll go with the nice round number.) Fifteen grams of CO2 is thus equivalent to 0.03 kilowatt-hours, enough to run a 2kw kettle for 54 seconds. That's a pretty fast boil - it would seem that Wissner-Gross' kettle isn't very full, or (shock) that he's massaging his figures as hard as he can to get a nice headline-grabbing number. Remember, Wissner-Gross' company is dependent on the idea that IT is a big environmental burden - he needs kettle energy consumption to be small here.
Actually, reliable old Which? reckon that boiling a kettle takes 0.103 to 0.12 kilowatt-hours. The right figure for a kettle boil, then, is between 50 and 60g of CO2. Let's be kind to Wissner-Gross and say 50.
The Harvard prof says that a Google search, meanwhile, uses energy equivalent to 7g of CO2 emissions. His research isn't yet published, so we'll just have to take that on trust - though Google dispute it vigorously.
So actually it isn't two Googles = one kettle boil, even by Wissner-Gross' own figures. It's at least seven, more likely eight+ Googles before you've caused the same carbon emissions as you would boiling a kettle.
Crikey, though - that's a lot of greenhouse gas, isn't it? Maybe we shouldn't use computers and IT so much. Or anyway, if we do, we should give Wissner-Gross some guilt money to green up our websites using his co2stats.com magic.
Or, more usefully, we could simply take to lighting our farts.
No, really. Farting and failing to burn off the resulting methane is incredibly environmentally irresponsible. The average person emits anywhere from half a litre to three litres of evil-smelling gas daily. Some of this is CO2, but we shouldn't blame ourselves there - the food we eat absorbs atmospheric carbon as it grows, we are effectively biofuelled and we can ignore that.
But, thanks to our intestinal bacteria, many of us also emit carbon in the form of methane, which is a vastly more potent greenhouse gas than CO2 - 25 times as bad for the planet, in fact. According to the Encyclopaedia Britannica, "up to ten per cent" of human intestinal gas is methane. Assuming five per cent, and a middle-of the-road 2l of daily bottomnal emissions, we are each putting out a cool (well, warm) 0.07 grams of CH4 every day. That has the same planet-busting effect as emitting about 2g of CO2, and it's not compensated for by our biofuelled food chain.