Both diesel and gasoline are about 85% carbon w/w

A better way to express that, per NIST SP 811, would be "Both diesel fuel and gasoline have a carbon mass fraction of 850 g/kg" or ""Both diesel fuel and gasoline have a carbon mass fraction of 0.85 kg/kg".

Jim
On 2013-04-24 17:45, John M. Steele wrote:
1) Monroney sticker requires CO2 in grams per mile.  It is normally not
used in advertising here.  It is largely a waste of space as it can be
accurately caklculated from fuel economy data:
*44 g of CO2 requires 12 g of C in fuel
*Both diesel and gasoline are about 85% carbon w/w
*Density of gasoline around 0.74 kg/L, disel 0.84 kg/L
(the 2nd and 3rd assumptions can be replaced with better data if available)
2) Evidently

------------------------------------------------------------------------
*From:* Martin Vlietstra <[email protected]>
*To:* U.S. Metric Association <[email protected]>
*Sent:* Wed, April 24, 2013 4:57:56 PM
*Subject:* [USMA:52692] RE: Oops: Imperial or Customary?

Was this written by a journalist?  If so

1.They probably do not know how to convert g/km to oz/mile (is that what
is used in the US)

2.They are probably unaware that the UK gallon is larger than the US gallon.

If on the other hand it was written by an advertising person, it might
well have been convenient to “forget” about the difference between the
UK and the US gallon.

*From:*[email protected] [mailto:[email protected]] *On
Behalf Of *John M. Steele
*Sent:* 24 April 2013 15:48
*To:* U.S. Metric Association
*Subject:* [USMA:52689] Oops: Imperial or Customary?

US website "borrows" report from UK website on how green the Ford Fiesta
(diesel) is:

http://usdailyvoice.com/ford-fiesta-hyped-by-u-k-website-as-top-green-car-of-the-year-1958.html#comment-395

"According to official (metric system) figures, the 2013 Ford Fiesta’s
emissions are now at only 87 g/km carbon dioxide. This would be for the
1.6-liter diesel variant, which is also capable of 85.6 miles per gallon
in the combined cycle,"

The CO2 figures make it look like the mpg is proabaly Imperial, and
Googling for the original UK source, they use the same figures which are
unlikely to be based on the US gallon:

http://www.thegreencarwebsite.co.uk/blog/index.php/2013/04/23/top-green-car-the-ford-fiesta-the-green-piece/

So he manages to change British "litre" to American "liter" but not to
fix the gallons.  He should have gone with L/100 km.


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