Hello Jan I think you have your answers. but here's the whole thing:
http://www.rsc.org/chemistryworld/News/2007/September/21090701.asp Biofuels could boost global warming, finds study Chemistry World 21 September 2007 Full research paper: N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels Abstract: http://www.atmos-chem-phys-discuss.net/7/11191/2007/acpd-7-11191-2007.html PDF: http://www.atmos-chem-phys-discuss.net/7/11191/2007/acpd-7-11191-2007.pdf HTH Best Keith >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. > >"One wants rational decisions rather than simply jumping on the bandwagon >because superficially something appears to reduce emissions," 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: "The significance of it is that the >supposed benefits of biofuels are even more disputable than had been thought >hitherto." > >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 "can >contribute as much or more to global warming by N2 O emissions than cooling >by fossil-fuel savings". > >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 "astounding insight". > >"It 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 >'biofuel' production while quickly abandoning others," he told the journal's >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/
