On Saturday 27 January 2007 15:24, Pat Naughtin wrote: > Dear Pierre, > > I have redone your calculation by going through these steps: > > I began by changing everything to SI units > > 1 cubic mile = (1609.344 metres)^3 = 4 168 181 825 cubic metres. > > The density of oil I took to be 920 kilograms per cubic metre taking an > average of three oils from California, 915 kg/m^3; Mexico, 973 kg/m^3; and > Texas, 873 kg/m^3 (See http://www.simetric.co.uk/si_liquids.htm ) > > The energy content of oil is assumed to be: 41.868 GJ/t = 41 868 000 > J/kg (See: > http://au.geocities.com/daveclarkecb/EnergyUnits.html#Energy%20content%20of >% 20fuels ) > > My calculation then went: > > 4 168 181 825 cubic metres x 920 kilograms per cubic metres x 41 868 000 > J/kg = 1.605 523 x 10^20 joules > > For convenience, I rounded this to 161 exajoules > > As we agree on the order of magnitude (exajoules) but disagree on the > calculated energy value, I wonder if you would check my assumptions and my > calculation.
Looks fine to me. My 37 refers to fat, which contains oxygen atoms, so burns with less energy than a pure hydrocarbon. The density I used is within the range of those three oils. Using the extremes, the cubic mile of oil could be anywhere from 152 to 170 exajoules. Pierre
