{"id":24827,"date":"2017-08-22T18:20:35","date_gmt":"2017-08-22T23:20:35","guid":{"rendered":"http:\/\/olduvai.ca\/?p=24827"},"modified":"2017-08-22T18:20:35","modified_gmt":"2017-08-22T23:20:35","slug":"quantifying-the-causes-of-the-recent-decrease-in-us-co2-emissions","status":"publish","type":"post","link":"https:\/\/olduvai.ca\/?p=24827","title":{"rendered":"Quantifying the causes of the recent decrease in US CO2 emissions"},"content":{"rendered":"<h3 class=\"entry-title\"><a href=\"http:\/\/euanmearns.com\/quantifying-the-causes-of-the-recent-decrease-in-us-co2-emissions\/#more-19345\">Quantifying the causes of the recent decrease in US CO2 emissions<\/a><\/h3>\n<div class=\"entry-content\">\n<p><img decoding=\"async\" src=\"http:\/\/thirdsunsolar.com\/wp-content\/uploads\/2014\/05\/Emissions.jpg\" alt=\"\" width=\"250\" align=\"left\" hspace=\"10\" \/>Between 2007 and 2015 total annual US CO2 emissions decreased by 740 million tons (12%). An updated analysis shows that 35% of this decrease was caused by natural gas replacing coal in electricity generation, 30% by lower fuel consumption in the transportation sector, 28% by renewables replacing coal in electricity generation and 7% by other factors. The 515-million-ton (20%) decrease in electricity sector emissions between 2007 and 2015 was 50% attributable to natural gas replacing coal, 40% to renewables replacing coal and 10% to other factors. These estimates do not allow for the impacts of the 2008-9 global recession on emissions growth, which could have resulted in annual US CO2 emissions now being as much as a billion tons less than they otherwise would have been. This estimate is, however, speculative.<\/p>\n<p>In previous posts <a href=\"http:\/\/euanmearns.com\/us-gdp-energy-consumption-and-co2-emissions\/\" target=\"blank\">here<\/a> and <a href=\"http:\/\/euanmearns.com\/the-causes-of-the-recent-decrease-in-us-greenhouse-gas-emissions\/\" target=\"blank\">here<\/a> Euan Mearns and I made approximate estimates of how much of the recent decrease in US emissions was caused by what. I came up with this:<\/p>\n<ul>\n<li><em>Gas replacing coal in electricity generation: 40%<\/em><\/li>\n<li><em>Decrease in gm\/mile vehicle CO2 emissions: 30%<\/em><\/li>\n<li><em>Growth in low-carbon renewables generation: 30%<\/em><\/li>\n<\/ul>\n<p>And Euan, using a more detailed approach (and also including the impacts of the 2008-9 recession, which I ignored), came up with this:<\/p>\n<ul>\n<li><em>Gas replacing coal 55 Mtoe \u2013 20%<\/em><\/li>\n<li><em>Fall in oil consumption owing to high price and recession 100 Mtoe \u2013 36%<\/em><\/li>\n<li><em>Fall in fuel oil consumption 25 Mtoe \u2013 9%<\/em><\/li>\n<li><em>Improved vehicle efficiency 26 Mtoe \u2013 9.5%<\/em><\/li>\n<li><em>Aviation, shipping and unallocated oil savings 29 Mtoe \u2013 10.5%<\/em><\/li>\n<li><em>[Biofuels 8.4 Mtoe]<\/em><\/li>\n<li><em>Growth in wind and solar 40 Mtoe \u2013 15%<\/em><\/li>\n<\/ul>\n<p>These estimates, particularly the \u201cgas replacing coal\u201d and the \u201cgrowth in renewables\u201d estimates, are a factor of two different. Other summaries to be found on the web range all the way from <a href=\"http:\/\/www.slate.com\/articles\/health_and_science\/project_syndicate\/2012\/09\/thanks_to_fracking_u_s_carbon_emissions_are_at_the_lowest_levels_in_20_years_.html\" target=\"blank\">\u201cfracking did it\u201d<\/a> to <a href=\"http:\/\/www.climatecentral.org\/news\/recession-caused-us-emissions-drop-19272\" target=\"blank\">\u201cthe global recession did it\u201d<\/a>.<\/p>\n<p>&#8230;click on the above link to read the rest of the article&#8230;<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Quantifying the causes of the recent decrease in US CO2 emissions Between 2007 and 2015 total annual US CO2 emissions decreased by 740 million tons (12%). An updated analysis shows that 35% of this decrease was caused by natural gas replacing coal in electricity generation, 30% by lower fuel consumption in the transportation sector, 28% [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[3,4],"tags":[146,11260,11990,827],"class_list":["post-24827","post","type-post","status-publish","format-standard","hentry","category-energy-2","category-environment","tag-co2-emissions","tag-energy-matters","tag-roger-andrews","tag-united-states"],"_links":{"self":[{"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/posts\/24827","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/olduvai.ca\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=24827"}],"version-history":[{"count":1,"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/posts\/24827\/revisions"}],"predecessor-version":[{"id":24828,"href":"https:\/\/olduvai.ca\/index.php?rest_route=\/wp\/v2\/posts\/24827\/revisions\/24828"}],"wp:attachment":[{"href":"https:\/\/olduvai.ca\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=24827"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/olduvai.ca\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=24827"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/olduvai.ca\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=24827"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}