Chris Fields' quote about liposuction is apt but it is not a critique of liposuction. Rather, it is a critique of eating huge amounts of dessert with no commensurate effort to burn off the calories.
It is absolutely correct to argue that we must not weaken efforts to cut emissions based on the hope of some future systems that might remove CO2 in meaningful quantities. But that is not an argument against efforts to develop such systems while we take stronger steps to cut emissions. David ________________________________ From: geoengineering@googlegroups.com <geoengineering@googlegroups.com> on behalf of Greg Rau <gh...@sbcglobal.net> Sent: Thursday, July 27, 2017 2:22 PM To: Geoengineering Subject: [geo] More on Climeworks via Roger Streit: https://www.reuters.com/article/us-climatechange-geoengineering-idUSKBN1AB0J3 Some interesting factoids: "...Climeworks began to suck greenhouse gases from thin air in May with giant fans and filters in a $23 million project that it calls the world's first "commercial carbon dioxide capture plant"" "Climeworks reckons it now costs about $600 to extract a tonne of carbon dioxide from the air and the plant's full capacity due by the end of 2017 is only 900 tonnes a year. That's equivalent to the annual emissions of only 45 Americans." >From the Climeworks website: "The majority of the energy required to run the >direct air capture plant comes from low-grade/waste heat." But what source of >electricity is powering the fans? If grid electricity then the C footprint >must be subtracted from the CO2 captured. How much? Also the CO2 is used to >grow food/plants, so the storage lifetime is <1yr. So is this a CDR scheme or >a CO2 emissions reduction scheme (by avoiding fossil-derived CO2 use)? 900 tonnes of CO2 extracted/yr: Assuming that a growing forest consumes and stores 5 tonnes CO2 yr^-1ha^-1, Climeworks is consuming CO2 at a rate equivalent to that of 180 hectares of forest. Cost/benefit/tradeoffs? Greg ""Relying on big future deployments of carbon removal technologies is like eating lots of dessert today, with great hopes for liposuction tomorrow," Christopher Field, a Stanford University professor of climate change, wrote in May." -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com<mailto:geoengineering+unsubscr...@googlegroups.com>. To post to this group, send email to geoengineering@googlegroups.com<mailto:geoengineering@googlegroups.com>. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
