Dear all, I would really like to read this study this report in original,since the article is producing several question marks. It is well known that the exhaust emissions from fatty acid methyl esters are producing higher amounts of nitrious gases than petro diesel does , but as far as I can remember, the nitrious oxide corresponds only to a tiny part of these. It is also well known that that the higher the cetane number of the biodiesel, the lower the emissions of nitrious gases. From that point it is a little bit strange to conclude that the the emissions of nitrious gases from rape seed oil biodiesel and maize biodiesel are the same, since the iodine number of maize oil in general is higher than the corresponding value of rape seed oil. This is suggesting in its prolongment that the emissions of nitrious gases from BD out of rape seed oil should be lower than from BD of maize oil. If the article is displaying the facts from the study correctly, then there are two ways to approach this problem: 1) Further product development of the fatty acid methyl esters in order to raise the cetane number to a level where the emissions of nitrious gases become acceptably lower. 2) New diesel veichles will be equipped with an Exhaust Gas Recirculation (EGR) system or an exhaust gas aftertreatment system which will lower the production of nitrious gases as required in Euro regulations. Information on the properties of nitrious oxide can be found at http://en.wikipedia.org/wiki/Nitrous_oxide No doubt has the information on the green house effects from nitrious oxide come from this sight, No matter if the conclusions from the study are right or not, it still makes sense to produce biodiesel, not in the least for forcing the development to take another path than previous. You know what I mean.
Jan Warnqvist ----- Original Message ----- From: "Olivier Morf" <[EMAIL PROTECTED]> To: <sustainablelorgbiofuel@sustainablelists.org> Sent: Friday, September 28, 2007 6:40 AM Subject: [Biofuel] Rapeseed Biofuel Produces More Greenhouse Gas Than Oil OrPetrol Source: http://www.timesonline.co.uk/tol/news/uk/science/article2507851.ece September 22, 2007 Rapeseed Biofuel Produces More Greenhouse Gas Than Oil Or Petrol By Lewis Smith A renewable energy source designed to reduce greenhouse gas emissions is contributing more to global warming than fossil fuels, a study suggests. Measurements of emissions from the burning of biofuels derived from rapeseed and maize have been found to produce more greenhouse gas emissions than they save. Other biofuels, especially those likely to see greater use over the next decade, performed better than fossil fuels but the study raises serious questions about some of the most commonly produced varieties. Rapeseed and maize biodiesels were calculated to produce up to 70 per cent and 50 per cent more greenhouse gases respectively than fossil fuels. The concerns were raised over the levels of emissions of nitrous oxide, which is 296 times more powerful as a greenhouse gas than carbon dioxide. Scientists found that the use of biofuels released twice as much as nitrous oxide as previously realised. The research team found that 3 to 5 per cent of the nitrogen in fertiliser was converted and emitted. In contrast, the figure used by the International Panel on Climate Change, which assesses the extent and impact of man-made global warming, was 2 per cent. The findings illustrated the importance, the researchers said, of ensuring that measures designed to reduce greenhouse-gas emissions are assessed thoroughly before being hailed as a solution. ³One wants rational decisions rather than simply jumping on the bandwagon because superficially something appears to reduce emissions,² said Keith Smith, a professor at the University of Edinburgh and one of the researchers. Maize for ethanol is the prime crop for biofuel in the US where production for the industry has recently overtaken the use of the plant as a food. In Europe the main crop is rapeseed, which accounts for 80 per cent of biofuel production. Professor Smith told Chemistry World: ³The significance of it is that the supposed benefits of biofuels are even more disputable than had been thought hitherto.² It was accepted by the scientists that other factors, such as the use of fossil fuels to produce fertiliser, have yet to be fully analysed for their impact on overall figures. But they concluded that the biofuels ³can contribute as much or more to global warming by N2 O emissions than cooling by fossil-fuel savings². The research is published in the journal Atmospheric Chemistry and Physics, where it has been placed for open review. The research team was formed of scientists from Britain, the US and Germany, and included Professor Paul Crutzen, who won a Nobel Prize for his work on ozone. Dr Franz Conen, of the University of Basel in Switzerland, described the study as an ³astounding insight². ³It is to be hoped that those taking decisions on subsidies and regulations will in future take N2O emissions into account and promote some forms of ¹biofuel¹ production while quickly abandoning others,² he told the journal¹s discussion board. Dr Dave Reay, of the University of Edinburgh, used the findings to calculate that with the US Senate aiming to increase maize ethanol production sevenfold by 2022, greenhouse gas emissions from transport will rise by 6 per cent. _______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/ _______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
