The US Dept. of Energy is a complete hodgepodge on this issue, best exemplied by the quote below (old data): http://www.eia.doe.gov/cneaf/electricity/page/co2_report/co2report.html
"In 1999,(2) estimated emissions of CO2 in the United States resulting from the generation of electric power were 2,245 million metric tons,(3) an increase of 1.4 percent from the 2,215 million metric tons in 1998. The estimated generation of electricity from all sources increased by 2.0 percent, going from 3,617 billion kilowatthours to 3,691 billion kilowatthours. Electricity generation from coal-fired plants, the primary source of CO2 emissions from electricity generation, was nearly the same in 1999 as in 1998. Much of the increase in electricity generation was produced by gas-fired plants and nuclear plants. The 1999 national average output rate,(4) 1.341 pounds of CO2 per kilowatthour generated, also showed a slight change from 1.350 pounds CO2 per kilowatthour in 1998 (Table 1)." They "sort of" use metric but throw in words like million and billion rather than using a suitable prefix. Then they go to abominable mixed units like pounds per kilowatt-hour. Since they are "accounting" for the CO2, I suppose it is not completely unreasonable to see them report the numbers like financial accountants instead of scientists. However, even using 0.608 kg of CO2 per kilowatthour would have been an improvement. Prefixes in the denominator should generally be avoided, but if this were expressed as CO2 emissions of 169 g/MJ, it could be compared to direct use of fuels. ________________________________ From: James R. Frysinger <[email protected]> To: U.S. Metric Association <[email protected]> Sent: Tue, April 13, 2010 9:50:31 PM Subject: [USMA:47119] Re: Carbon footprint question. Atmospheric scientists and climatologists use the metric ton for such things. That is not to say that all journalists, government officials, or members of the public realize that. Those folks might then use some other ton, which would not match the terminology in the literature. Jim Remek Kocz wrote: > Which ton is used for the carbon footprint in the US? Short ton or metric > ton? I saw that the recent Car and Driver magazine has been reporting > pounds/mile CO2 emissions figures for the cars they review, so I can only > assume when discussing tons of carbon produced by whatever entities, we're > using short tons. Correct? This reminds me of some incident a year or two > ago when the White House declared that they saved a bunch of money by paying > for their carbon footprint by the short ton rather than the metric ton. > > Remek -- James R. Frysinger 632 Stony Point Mountain Road Doyle, TN 38559-3030 (C) 931.212.0267 (H) 931.657.3107 (F) 931.657.3108
