tag:blogger.com,1999:blog-8441439.post1895510213701797770..comments2023-11-19T17:31:49.939+00:00Comments on Bristling Badger: london's hydrogen busesUnknownnoreply@blogger.comBlogger5125tag:blogger.com,1999:blog-8441439.post-39889558882542744262008-11-29T00:04:00.000+00:002008-11-29T00:04:00.000+00:00Just posted a comment and a link to your headherit...Just posted a comment and a link to your headheritage article on this: <BR/><BR/>http://www.newscientist.com/article/mg20026841.900-whatever-happened-to-the-hydrogen-economy.htmlpunksciencehttps://www.blogger.com/profile/05322481220029985750noreply@blogger.comtag:blogger.com,1999:blog-8441439.post-16260780377834574562008-07-31T15:12:00.000+01:002008-07-31T15:12:00.000+01:00Thanks for the clarification.I was pleased that yo...Thanks for the clarification.<BR/><BR/>I was pleased that your references and the transparency of your workings let me spot the incongruity in the first place.Owenhttps://www.blogger.com/profile/06153241381781786537noreply@blogger.comtag:blogger.com,1999:blog-8441439.post-85106913382554556062008-07-29T20:11:00.000+01:002008-07-29T20:11:00.000+01:00Owen, I asked a friend who knows about oil resourc...Owen, I asked a friend who knows about oil resources who said<BR/><BR/><I>The trouble is, energy accounting within the energy industry is a dark art, akin to voodoo I sometimes think. And often for good reason... the number of variables involved can often be unmanageable.<BR/><BR/>For instance, there can be a big energy expenditure involved in extracting the stuff from wells and transporting it to the refinery. With some wells (especially off-shore wells, or those employing enhanced-recovery techniques like gas injection) this energy might be quite large. With others, like some of the 'gushers' in the gulf, the stuff damn near pumps itself straight to the refinery.<BR/><BR/>So even before you fire up the oil refinery, you've got a potentially massive proportional variation in emissions.</I><BR/><BR/>All numbers on this stuff, even the sexy official stuff, can only ever be rough comparisons. But that'll do me in preference to no answer at all.<BR/><BR/><A HREF="http://www.anl.gov/" REL="nofollow">Argonne National Laboratory</A> is a US government Department of Energy project. They've done a lot of stuff on full cycle 'well to wheels' calculations for energy use and greenhouse gas emissions of various technologies.<BR/><BR/>I've also turned up stuff from the EU's <A HREF="http://ies.jrc.ec.europa.eu/wtw.html" REL="nofollow">Institute of Environment and Sustainability</A>. At first glance, their figures don't seem to match Argonne's. I'll do a big print-off and see what's what.<BR/><BR/>But in the meantime, the answer to our question is in the graph on page 3 of <A HREF="http://www.transportation.anl.gov/pdfs/TA/273.pdf" REL="nofollow">this Argonne PDF</A>. It says that 78% of gasoline emissions are pump-to-wheels and 22% well-to-pump. I've assumed those from diesel will be the same and amended the maths in the above post accordingly.<BR/><BR/>Thankyou for pointing that out. With these bits of pencil-chewing, it's often a team process to make it come clear. I'm glad to have any errors of fact or reasoning flagged up, it brings us closer to the truth.merrickhttps://www.blogger.com/profile/10959849087751101034noreply@blogger.comtag:blogger.com,1999:blog-8441439.post-77214290406788922362008-07-28T19:39:00.000+01:002008-07-28T19:39:00.000+01:00Owen, you're right. What a glaring omission.As is ...Owen, you're right. What a glaring omission.<BR/><BR/>As is probably clear, I'm no scientist and have no expertise in this area. However, I can't find anyone who's publishing a g/km comparison. Worse, there's a ton of stuff from industry and news media saying hydrogen is 'zero-emission'. <BR/><BR/>So I'm trying to get reliable numbers and do a back-of-an-envelope sum to at least give us a rough idea.<BR/><BR/>I'll look into refining emissions and post again here. <BR/><BR/>Given that CUTE and others concede that there's a greater climate impact from most methods of making hydrogen, I suspect it'll change the numbers but not the conclusion.<BR/><BR/>The thing they all point to is the 'but we can make it by electrolysis from renewable electricity' thing.<BR/><BR/>The Tyndall Centre's figure is utterly damning on that. <BR/><BR/>What renewables we have are better off displacing coal-fired power stations. <BR/><BR/>And given the remarkable inefficiency of hydrogen as a way to store electricity, even if the grid were magically instantly 100% renewable, I can't think of any reason to make vehicle-hydrogen that isn't a stronger reason to make battery vehicles.merrickhttps://www.blogger.com/profile/10959849087751101034noreply@blogger.comtag:blogger.com,1999:blog-8441439.post-50046772713855194492008-07-28T14:21:00.000+01:002008-07-28T14:21:00.000+01:00For the avoidance of doubt, can you confirm whethe...For the avoidance of doubt, can you confirm whether or not the standard diesel bus figures include the effect of getting the diesel into a usable state? As far as I can see, you are comparing two different things: running costs for diesel vs running <I>and production</I> costs for hydrogen.<BR/><BR/>This may not make much, or any, difference to the conclusion, but I'd prefer to know that rather than assume it.Owenhttps://www.blogger.com/profile/06153241381781786537noreply@blogger.com