{"id":21244,"date":"2020-07-06T19:36:55","date_gmt":"2020-07-06T19:36:55","guid":{"rendered":"https:\/\/www.lifeandnews.com\/articles\/?p=21244"},"modified":"2020-07-08T12:59:49","modified_gmt":"2020-07-08T12:59:49","slug":"renewable-natural-gas-may-sound-green-but-its-not-an-antidote-for-climate-change","status":"publish","type":"post","link":"https:\/\/www.lifeandnews.com\/articles\/renewable-natural-gas-may-sound-green-but-its-not-an-antidote-for-climate-change\/","title":{"rendered":"&#8216;Renewable&#8217; natural gas may sound green, but it&#8217;s not an antidote for climate change"},"content":{"rendered":"<p><a href=\"https:\/\/theconversation.com\/profiles\/emily-grubert-1073250\">Emily Grubert<\/a>, <em><a href=\"https:\/\/theconversation.com\/institutions\/georgia-institute-of-technology-1310\">Georgia Institute of Technology<\/a><\/em><\/p>\n<p>Natural gas is a versatile fossil fuel that accounts for <a href=\"https:\/\/www.eia.gov\/totalenergy\/data\/browser\/index.php?tbl=T01.03#\/?f=A&amp;start=200001\">about a third of U.S. energy use<\/a>. Although it produces fewer greenhouse gas emissions and other pollutants than coal or oil, natural gas is a major contributor to climate change, an <a href=\"https:\/\/www.ipcc.ch\/sr15\/\">urgent global problem<\/a>. Reducing emissions from the natural gas system is especially challenging because natural gas is used <a href=\"https:\/\/www.eia.gov\/dnav\/ng\/ng_cons_sum_dcu_nus_m.htm\">roughly equally for electricity, heating, and industrial applications<\/a>.<\/p>\n<p>There\u2019s an emerging argument that maybe there could be a direct substitute for fossil natural gas in the form of renewable natural gas (RNG) \u2013 a renewable fuel designed to be nearly indistinguishable from fossil natural gas. RNG could be made from biomass or from captured carbon dioxide and electricity.<\/p>\n<p>Based on what\u2019s known about these systems, however, I believe climate benefits might not be as large as advocates claim. This matters because RNG isn\u2019t widely used yet, and decisions about whether to invest in it are being made now, in places like <a href=\"https:\/\/www.cleanenergyfuels.com\/blog\/influx-of-california-rng-fuels-local-economy-protects-climate\">California<\/a>, <a href=\"https:\/\/www.oregon.gov\/energy\/Get-Involved\/Pages\/RNG-Advisory-Committee.aspx\">Oregon<\/a>, <a href=\"http:\/\/biomassmagazine.com\/articles\/15172\/inslee-signs-bill-to-promote-rng-in-state-of-washington\">Washington<\/a>, <a href=\"https:\/\/energynews.us\/2019\/12\/03\/midwest\/michigan-utilities-see-role-for-renewable-natural-gas-but-cost-barrier-remains\/\">Michigan<\/a>, <a href=\"https:\/\/investor.southerncompany.com\/information-for-investors\/latest-news\/latest-news-releases\/press-release-details\/2020\/Southern-Company-Gas-grows-leadership-team-to-focus-on-climate-action-innovation-and-renewable-natural-gas-strategy\/default.aspx\">Georgia<\/a> and <a href=\"https:\/\/www.epa.gov\/natural-gas-star-program\/rng-interconnect-guideline-new-york\">New York<\/a>.<\/p>\n<p>As someone who studies <a href=\"https:\/\/scholar.google.com\/citations?user=3RI02dcAAAAJ&amp;hl=en\">sustainability<\/a>, I research how decisions made now might influence the environment and society in the future. I\u2019m particularly interested in how energy systems contribute to climate change.<\/p>\n<p>Right now, energy is responsible for most of the pollution worldwide that <a href=\"https:\/\/www.ipcc.ch\/report\/ar5\/syr\/\">causes climate change<\/a>. Since energy infrastructure, like power plants and pipelines, <a href=\"http:\/\/emilygrubert.org\/wp-content\/uploads\/2019\/02\/eia_860_2017_map.html\">lasts a long time<\/a>, it\u2019s important to consider the climate change emissions that society <a href=\"https:\/\/doi.org\/10.1038\/s41586-019-1364-3\">is committing to<\/a> with new investments in these systems. At the moment, renewable natural gas is more a proposal than reality, which makes this a great time to ask: What would investing in RNG mean for climate change?<\/p>\n<figure><iframe loading=\"lazy\" src=\"https:\/\/www.youtube.com\/embed\/3KaMnkmf0tc?wmode=transparent&amp;start=0\" width=\"440\" height=\"260\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><figcaption><span class=\"caption\">Marketing video from Southern California Gas Co. promoting renewable natural gas as a climate-friendly energy option.<\/span><\/figcaption><\/figure>\n<h2>What RNG is and why it matters<\/h2>\n<p>Most equipment that uses energy can only use a single kind of fuel, but the fuel might come from different resources. For example, you can\u2019t charge your computer with gasoline, but it can run on electricity generated from coal, natural gas or solar power.<\/p>\n<p>Natural gas is almost pure methane, <a href=\"https:\/\/www.eia.gov\/energyexplained\/natural-gas\/\">currently sourced<\/a> from raw, fossil natural gas produced from <a href=\"https:\/\/www.eia.gov\/energyexplained\/natural-gas\/where-our-natural-gas-comes-from.php\">deposits deep underground<\/a>. But methane could come from renewable resources, too.<\/p>\n<p>[<em>The Conversation\u2019s science, health and technology editors pick their favorite stories.<\/em> <a href=\"https:\/\/theconversation.com\/us\/newsletters\/science-editors-picks-71\/?utm_source=TCUS&amp;utm_medium=inline-link&amp;utm_campaign=newsletter-text&amp;utm_content=science-favorite\">Weekly on Wednesdays<\/a>.]<\/p>\n<p>Two main methane sources could be used to make RNG. First is <a href=\"https:\/\/www.epa.gov\/ghgemissions\/inventory-us-greenhouse-gas-emissions-and-sinks\">biogenic methane<\/a>, produced by bacteria that digest organic materials in manure, landfills and wastewater. Wastewater treatment plants, landfills and dairy farms have captured and used biogenic methane as an energy resource for <a href=\"http:\/\/emilygrubert.org\/wp-content\/uploads\/2019\/02\/eia_860_2017_map.html\">decades<\/a>, in a form usually called <a href=\"https:\/\/www.eia.gov\/energyexplained\/biomass\/landfill-gas-and-biogas.php\">biogas<\/a>.<\/p>\n<figure class=\"align-center \"><img src=\"https:\/\/images.theconversation.com\/files\/343781\/original\/file-20200624-133013-vi71ef.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip\" sizes=\"(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px\" srcset=\"https:\/\/images.theconversation.com\/files\/343781\/original\/file-20200624-133013-vi71ef.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=600&amp;h=400&amp;fit=crop&amp;dpr=1 600w, https:\/\/images.theconversation.com\/files\/343781\/original\/file-20200624-133013-vi71ef.jpg?ixlib=rb-1.1.0&amp;q=30&amp;auto=format&amp;w=600&amp;h=400&amp;fit=crop&amp;dpr=2 1200w, https:\/\/images.theconversation.com\/files\/343781\/original\/file-20200624-133013-vi71ef.jpg?ixlib=rb-1.1.0&amp;q=15&amp;auto=format&amp;w=600&amp;h=400&amp;fit=crop&amp;dpr=3 1800w, https:\/\/images.theconversation.com\/files\/343781\/original\/file-20200624-133013-vi71ef.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;h=503&amp;fit=crop&amp;dpr=1 754w, https:\/\/images.theconversation.com\/files\/343781\/original\/file-20200624-133013-vi71ef.jpg?ixlib=rb-1.1.0&amp;q=30&amp;auto=format&amp;w=754&amp;h=503&amp;fit=crop&amp;dpr=2 1508w, https:\/\/images.theconversation.com\/files\/343781\/original\/file-20200624-133013-vi71ef.jpg?ixlib=rb-1.1.0&amp;q=15&amp;auto=format&amp;w=754&amp;h=503&amp;fit=crop&amp;dpr=3 2262w\" alt=\"\" \/><figcaption><span class=\"caption\">Methane captured from cow manure can be used to produce renewable natural gas, which energy companies are promoting as a replacement for fossil natural gas.<\/span><br \/>\n<span class=\"attribution\"><a class=\"source\" href=\"http:\/\/www.apimages.com\/metadata\/Index\/Exchange-Cow-Manure-Renewables\/be42da9d774e40b98ea4e1a332de3423\/15\/0\">AP Photo\/Rodrigo Abd<\/a><\/span><\/figcaption><\/figure>\n<p>Some biogenic methane is generated naturally when organic materials break down without oxygen. Burning it for energy can be beneficial for the climate if doing so prevents methane from escaping to the atmosphere.<\/p>\n<p>In theory, there\u2019s enough of this climate-friendly methane available to replace <a href=\"https:\/\/iopscience.iop.org\/article\/10.1088\/1748-9326\/ab9335\/meta\">about 1% of the energy<\/a> that the current natural gas system provides. The largest share is found at landfills.<\/p>\n<p>The other source for RNG doesn\u2019t exist in practice yet, but could theoretically be a much larger resource than biogenic methane. Often called <a href=\"https:\/\/www.powermag.com\/why-power-to-gas-may-flourish-in-a-renewables-heavy-world\/\">power-to-gas<\/a>, this methane would be intentionally manufactured from carbon dioxide and hydrogen using electricity. If all the inputs are climate-neutral \u2013 meaning, for example, that the electricity used to create the RNG is generated from resources without greenhouse gas emissions \u2013 then the combusted RNG would also be climate-neutral.<\/p>\n<figure class=\"align-center zoomable\"><a href=\"https:\/\/images.theconversation.com\/files\/344892\/original\/file-20200630-103683-11bkmyl.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=1000&amp;fit=clip\"><img src=\"https:\/\/images.theconversation.com\/files\/344892\/original\/file-20200630-103683-11bkmyl.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip\" sizes=\"(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px\" srcset=\"https:\/\/images.theconversation.com\/files\/344892\/original\/file-20200630-103683-11bkmyl.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=600&amp;h=450&amp;fit=crop&amp;dpr=1 600w, https:\/\/images.theconversation.com\/files\/344892\/original\/file-20200630-103683-11bkmyl.jpg?ixlib=rb-1.1.0&amp;q=30&amp;auto=format&amp;w=600&amp;h=450&amp;fit=crop&amp;dpr=2 1200w, https:\/\/images.theconversation.com\/files\/344892\/original\/file-20200630-103683-11bkmyl.jpg?ixlib=rb-1.1.0&amp;q=15&amp;auto=format&amp;w=600&amp;h=450&amp;fit=crop&amp;dpr=3 1800w, https:\/\/images.theconversation.com\/files\/344892\/original\/file-20200630-103683-11bkmyl.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;h=566&amp;fit=crop&amp;dpr=1 754w, https:\/\/images.theconversation.com\/files\/344892\/original\/file-20200630-103683-11bkmyl.jpg?ixlib=rb-1.1.0&amp;q=30&amp;auto=format&amp;w=754&amp;h=566&amp;fit=crop&amp;dpr=2 1508w, https:\/\/images.theconversation.com\/files\/344892\/original\/file-20200630-103683-11bkmyl.jpg?ixlib=rb-1.1.0&amp;q=15&amp;auto=format&amp;w=754&amp;h=566&amp;fit=crop&amp;dpr=3 2262w\" alt=\"\" \/><\/a><figcaption><span class=\"caption\">Digesters at the Deer Island water treatment plant on Boston Harbor break down sewage sludge, yielding methane gas that helps power the plant.<\/span><br \/>\n<span class=\"attribution\"><a class=\"source\" href=\"https:\/\/en.wikipedia.org\/wiki\/Deer_Island_Waste_Water_Treatment_Plant#\/media\/File:Deerislandeggs.jpg\">Frank Hebbert\/Wikipedia<\/a>, <a class=\"license\" href=\"http:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY<\/a><\/span><\/figcaption><\/figure>\n<p>So far, RNG of either type isn\u2019t widely available. Much of the current conversation focuses on whether and how to make it available. For example, <a href=\"https:\/\/www.sempra.com\/socalgas-takes-next-step-toward-offering-renewable-natural-gas\">SoCalGas in California<\/a>, <a href=\"https:\/\/energynews.us\/2019\/01\/30\/midwest\/minnesota-utility-wants-to-offer-customers-renewable-natural-gas-option\/\">CenterPoint Energy in Minnesota and Vermont Gas Systems in Vermont<\/a> either offer or have proposed offering RNG to consumers, in the same way that many utilities allow customers to opt in to renewable electricity.<\/p>\n<h2>Renewable isn\u2019t always sustainable<\/h2>\n<p>If RNG could be a renewable replacement for fossil natural gas, why not move ahead? Consumers have shown that they are <a href=\"https:\/\/www.nrel.gov\/analysis\/green-power.html\">willing to buy renewable electricity<\/a>, so we might expect similar enthusiasm for RNG.<\/p>\n<p>The key issue is that methane isn\u2019t just a fuel \u2013 it\u2019s also a <a href=\"https:\/\/www.eia.gov\/environment\/emissions\/ghg_report\/ghg_overview.php\">potent greenhouse gas<\/a> that contributes to climate change. Any methane that is manufactured intentionally, whether from biogenic or other sources, will contribute to climate change if it enters the atmosphere.<\/p>\n<p>And <a href=\"http:\/\/DOI.org\/10.1126\/science.aar7204\">releases<\/a> <a href=\"https:\/\/doi.org\/10.1016\/j.wasman.2019.07.029\">will happen<\/a>, from newly built production systems and <a href=\"https:\/\/theconversation.com\/why-methane-emissions-matter-to-climate-change-5-questions-answered-122684\">existing, leaky transportation and user infrastructure<\/a>. For example, the moment you smell gas before the pilot light on a stove lights the ring? That\u2019s methane leakage, and it contributes to climate change.<\/p>\n<p>To be clear, RNG is almost certainly better for the climate than fossil natural gas because byproducts of burning RNG won\u2019t contribute to climate change. But doing somewhat better than existing systems is no longer enough to respond to the <a href=\"https:\/\/doi.org\/10.1038\/nclimate2923\">urgency<\/a> of climate change. The world\u2019s <a href=\"https:\/\/www.ipcc.ch\/sr15\/chapter\/spm\/\">primary international body on climate change<\/a> suggests we need to decarbonize by 2030 to mitigate the worst effects of climate change.<\/p>\n<figure class=\"align-center zoomable\"><a href=\"https:\/\/images.theconversation.com\/files\/343794\/original\/file-20200624-132955-1k1d4pm.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=1000&amp;fit=clip\"><img src=\"https:\/\/images.theconversation.com\/files\/343794\/original\/file-20200624-132955-1k1d4pm.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip\" sizes=\"(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px\" srcset=\"https:\/\/images.theconversation.com\/files\/343794\/original\/file-20200624-132955-1k1d4pm.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=600&amp;h=338&amp;fit=crop&amp;dpr=1 600w, https:\/\/images.theconversation.com\/files\/343794\/original\/file-20200624-132955-1k1d4pm.jpg?ixlib=rb-1.1.0&amp;q=30&amp;auto=format&amp;w=600&amp;h=338&amp;fit=crop&amp;dpr=2 1200w, https:\/\/images.theconversation.com\/files\/343794\/original\/file-20200624-132955-1k1d4pm.jpg?ixlib=rb-1.1.0&amp;q=15&amp;auto=format&amp;w=600&amp;h=338&amp;fit=crop&amp;dpr=3 1800w, https:\/\/images.theconversation.com\/files\/343794\/original\/file-20200624-132955-1k1d4pm.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;h=424&amp;fit=crop&amp;dpr=1 754w, https:\/\/images.theconversation.com\/files\/343794\/original\/file-20200624-132955-1k1d4pm.jpg?ixlib=rb-1.1.0&amp;q=30&amp;auto=format&amp;w=754&amp;h=424&amp;fit=crop&amp;dpr=2 1508w, https:\/\/images.theconversation.com\/files\/343794\/original\/file-20200624-132955-1k1d4pm.jpg?ixlib=rb-1.1.0&amp;q=15&amp;auto=format&amp;w=754&amp;h=424&amp;fit=crop&amp;dpr=3 2262w\" alt=\"\" \/><\/a><figcaption><span class=\"caption\">Renewable natural gas would compete with other energy sources, such as wind power, that do not emit greenhouse gases to the atmosphere.<\/span><br \/>\n<span class=\"attribution\"><a class=\"source\" href=\"http:\/\/www.apimages.com\/metadata\/Index\/Carbon-Pricing-New-York\/9aa3909b7478409386ed2f2b56eb961a\/86\/0\">AP Photo\/Julie Jacobson<\/a><\/span><\/figcaption><\/figure>\n<h2>Scant climate benefits<\/h2>\n<p><a href=\"https:\/\/iopscience.iop.org\/article\/10.1088\/1748-9326\/ab9335\/meta\">My recent research<\/a> suggests that for a system large enough to displace a lot of fossil natural gas, RNG is probably not as good for the climate as <a href=\"https:\/\/investor.southerncompany.com\/information-for-investors\/latest-news\/latest-news-releases\/press-release-details\/2020\/Southern-Company-Gas-grows-leadership-team-to-focus-on-climate-action-innovation-and-renewable-natural-gas-strategy\/default.aspx\">is publicly claimed<\/a>. Although RNG has lower climate impact than its fossil counterpart, likely high demand and methane leakage mean that it probably will contribute to climate change. In contrast, renewable sources such as wind and solar energy do not <a href=\"https:\/\/www.eia.gov\/environment\/emissions\/carbon\/\">emit climate pollution directly<\/a>.<\/p>\n<p>What\u2019s more, creating a large RNG system would require building mostly new production infrastructure, since RNG comes from different sources than fossil natural gas. Such investments are both long-term commitments and opportunity costs. They would devote money, political will and infrastructure investments to RNG instead of alternatives that could achieve a zero greenhouse gas emission goal.<\/p>\n<p>When climate change first <a href=\"https:\/\/www.nytimes.com\/1988\/06\/24\/us\/global-warming-has-begun-expert-tells-senate.html\">broke into the political conversation<\/a> in the late 1980s, investing in long-lived systems with low but non-zero greenhouse gas emissions was still compatible with aggressive climate goals. Now, zero greenhouse gas emissions is the target, and my research suggests that large deployments of RNG likely won\u2019t meet that goal.<!-- Below is The Conversation's page counter tag. Please DO NOT REMOVE. --><img loading=\"lazy\" style=\"border: none !important; box-shadow: none !important; margin: 0 !important; max-height: 1px !important; max-width: 1px !important; min-height: 1px !important; min-width: 1px !important; opacity: 0 !important; outline: none !important; padding: 0 !important; text-shadow: none !important;\" src=\"https:\/\/counter.theconversation.com\/content\/138791\/count.gif?distributor=republish-lightbox-basic\" alt=\"The Conversation\" width=\"1\" height=\"1\" \/><!-- End of code. If you don't see any code above, please get new code from the Advanced tab after you click the republish button. The page counter does not collect any personal data. More info: https:\/\/theconversation.com\/republishing-guidelines --><\/p>\n<p><a href=\"https:\/\/theconversation.com\/profiles\/emily-grubert-1073250\">Emily Grubert<\/a>, Assistant Professor of Civil and Environmental Engineering, <em><a href=\"https:\/\/theconversation.com\/institutions\/georgia-institute-of-technology-1310\">Georgia Institute of Technology<\/a><\/em><\/p>\n<p>This article is republished from <a href=\"https:\/\/theconversation.com\">The Conversation<\/a> under a Creative Commons license. Read the <a href=\"https:\/\/theconversation.com\/renewable-natural-gas-may-sound-green-but-its-not-an-antidote-for-climate-change-138791\">original article<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Emily Grubert, Georgia Institute of Technology Natural gas is a versatile fossil fuel that accounts for about a third of U.S. energy use. Although it produces fewer greenhouse gas emissions and other pollutants than coal or oil, natural gas is a major contributor to climate change, an urgent global problem. Reducing emissions from the natural [&hellip;]<\/p>\n","protected":false},"author":44,"featured_media":21245,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1862],"tags":[8317,8318,139,3518,4335,4966,5340,4232,2324,2326],"_links":{"self":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/21244"}],"collection":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/users\/44"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/comments?post=21244"}],"version-history":[{"count":2,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/21244\/revisions"}],"predecessor-version":[{"id":21258,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/21244\/revisions\/21258"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/media\/21245"}],"wp:attachment":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/media?parent=21244"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/categories?post=21244"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/tags?post=21244"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}