Comment by jws | Hacker News Reader

Comment by jws | Hacker News Reader

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I find myself unable to offer an opinion, let's find out.

NOTICE: maxs points out I missed a x1000 on the barrel count, the following is off by three orders of magnitude:

In 2008 the world consumed 5269 barrels of jet fuel per day. 42 gallons in a barrel, 6.8 pounds per gallon, 0.45kg/pound, kerosene has 43MJ/kg… that is 29 terajoules (or I made a mistake). [1] [2]

Spread 29TJ out over the day and that is 29TJ /24/60/60 and you get 337 megawatts (or I made a mistake, this feels low, but I'll go with the calculation). [3]

Google's data centers drew 260 megawatts in 2011. [4]

So, there you go. Google's data centers alone use three quarters as much energy as all jet airplanes combined.

EOM

[1] http://www.indexmundi.com/energy.aspx?product=jet-fuel&g...

[2] http://large.stanford.edu/courses/2010/ph240/glover2/

[3] http://en.wikipedia.org/wiki/Watt

[4] http://www.nytimes.com/2011/09/09/technology/google-details-...

You're off by 3 orders of magnitude. 5269 barrels a day did sound too little to me. In the link you cited the quantity is given in thousands of barrels. The daily use is 5269000 barrels a day.

Thanks for finding that. The result seemed odd.

So 337 gigawatts for jet fuel instead of megawatts. That will dwarf google, we'll need to compare to something bigger.

Lets convert to annual kilowatt hours, 337GW24h365= 2950 billion kWh.

In 2007 it was estimated that the total power consumption of the internet was 868 billion kWh. [1]

So now we have three times the energy in jet air transport as in powering the internet. I have to say this feels better.

EOM

[1] http://uclue.com/index.php?xq=724

You're off by a factor of 1000, I think. The chart has units in thousands. So it consumes more than 5,269,000 barrels per day -- yielding 29 PJ or 337 GW continuously.

Edit: Whoops. maxs has priority.

Nice analysis but my question was in the context of a drone (that the article mentioned) :) I could not imagine that any sort of power requirement for computing in those drones can come even near to the amount of fuel they are burning to fly.

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