January 23, 2023

Environmental, Natural Resources, & Energy Law Blog

Manure-to-Energy Projects – Greenwashing or a Real Solution to Reducing Methane Emissions from Livestock Production? - Patty Keough


Patty Keough

Manure-to-Energy Projects – Greenwashing or a Real Solution to Reducing Methane Emissions from Livestock Production?

CAFOs and manure.

In the U.S., billions of food animals are raised in Concentrated Animal Feeding Operations (CAFOs) – which are commonly referred to as “factory farms.”[1] Unsurprisingly, CAFOs produce an incredible amount of manure: between 2,800 tons to 1.6 million tons a year at a single CAFO depending on the size of the CAFO and how many animals it houses.[2] According to estimates, livestock in the U.S. produce between 3-20 times more manure than humans in the U.S. – as much as 1.37 billion tons of manure per year.[3] And while human waste is treated in sewage treatment plants, CAFOs typically store untreated waste in huge anaerobic waste storage pits or structures for as long as six months until the waste is disposed of by applying it to farm fields.[4]

The stunning amount of livestock waste CAFOs produce not only leads to harmful environmental and human health effects,[5] it also contributes to climate change. According to the EPA, livestock manure management is the fifth biggest source of methane emissions in the U.S.[6] Although carbon dioxide is generally thought of as the most concerning greenhouse gas, methane is over 25 times more potent than carbon dioxide at trapping heat in the atmosphere.[7]

Supported by tax credits and other incentives, big livestock producers in the U.S. are partnering with energy companies and investing in manure digesters that turn manure into biogas, characterizing these “manure-to-energy” projects as a sustainable solution to methane emissions from livestock manure. Policymakers and agribusiness tout these projects as a “win-win,” claiming that they are not only effective for reducing methane but also for dealing with the environmental impacts resulting from all of that manure.[8] However, the actual benefits of these manure-to-energy projects are far from clear and their critics contend that these projects will only encourage the expansion of CAFOs, which in turn will lead to more animals, more manure, and more methane.

Manure-to-energy projects – What are they?

Manure-to-energy projects rely on anaerobic methane digesters to produce energy in the form of biogas from livestock manure, particularly from dairy and hog CAFOs.[9] The methane is converted into biogas by flushing the manure into huge lagoons, where the manure emits methane.[10] A cover is placed on the lagoon and the manure runs into the digester, which then uses microorganisms to break down organic matter to release methane.[11] The methane is then captured and pipelines pump it to a facility which processes the methane into biogas and injects it into a bigger pipeline.[12] The resultant biogas is then used to generate electricity or as fuel.[13]

Incentives for the development of manure-to-energy projects have led to partnerships between livestock industry giants and energy companies. For instance, in 2018, Smithfield Foods – the largest pork producer in the world – and Dominion Energy entered into a $500 million joint venture called Align RNG to turn pig manure into biogas.[14] The alliance will result in the largest manure-to-energy project in the state of North Carolina.[15] Since then, other partnerships have been announced, including collaborations between Duke Energy and dairy farmers in the southeast United States, and one between Chevron and California Biogas and California dairy farmers.[16]

As mentioned, a number of incentives are encouraging the development of manure-to-energy projects, including the Biden Administration’s U.S. Methane Emissions Reductions Action Plan (“Biden Methane Plan”).[17] Notably, for methane emissions associated with livestock production, the Biden Methane Plan depends nearly entirely on government subsidies and grants for the use of methane digesters on large-scale livestock operations.[18] These include the use of conservation programs like the Environmental Quality Incentives Program (EQIP), the AgStar Program, the Rural Business Cooperative Service, and the Rural Energy for America Program to subsidize construction and use of methane digesters.[19] The Inflation Reduction Act also includes tax credits for companies that invest in anaerobic digesters.[20]

Even before the Biden Methane Plan and the Inflation Reduction Act, other programs and policies were already encouraging the proliferation of methane digesters. One of these is California’s Low Carbon Fuel Standard (LCFS), which aims to reduce emissions from the state’s transportation sector by 20% by 2030.[21] Biogas from livestock operations are eligible for credits under the LCFS scoring system; this is not limited to livestock operations in California – operations in other states can sell credits into the California Market, and LCFS credits are frequently combined with other federal and state subsidies to enhance the profitability of methane digesters.[22]

 What’s wrong with manure-to-energy projects?

Critics highlight a number of problems with manure-to-energy projects. Notably, biogas is not that sustainable; manure digesters depend on large-scale industrial animal production, which is concerning for environmental justice reasons;[23] manure-to-energy projects can be costly and require expansion of natural gas distribution lines; they may accidentally leak or spill liquid manure; and they typically rely on government funding that could instead be used on more effective greenhouse gas mitigation projects.[24] Lastly, manure digesters do nothing to curb enteric methane emissions – methane emissions that result from cow belches.[25]

Not that sustainable: Proponents of manure-to-energy projects contend that disposing of livestock waste this way is more environmentally sound than letting it leak into waterways and get into the air,[26] but these benefits are minimal compared to the new environmental impacts from these projects. Simply put, biogas is not as sustainable as its proponents contend. To produce and transport biogas, pipelines, fleets of trucks, and interconnection with local power grids are necessary – all of which, at least potentially, involve fossil fuels.[27] The burning of biogas still emits carbon dioxide and other air contaminants, and the gas pipelines and other necessary infrastructure for manure-to-energy projects can themselves leak large amounts of methane.[28] In fact, estimates put leakage from biogas pipelines and facilities at “between 2-4% and up to 15% of total biogas production.”[29] Biogas is also extremely toxic, flammable, and possibly explosive.[30] If not properly maintained, manure digesters themselves can leak, break down, or explode.[31] Repairing faulty digesters can be dangerous and requires professional divers;[32] in 2021, an experienced diver drowned while attempting to repair a cable in a million-gallon anaerobic digester at a cattle farm in Iowa.[33]

Costly: Manure digesters are extremely expensive to build and to maintain.[34] Digesters that are used to sell biogas off-farm cost about $4.2 million for a dairy CAFO with 2,000 cows.[35] Digesters also need a lot of manure to generate energy – because of this, a USDA economic analysis questioned the economic viability of digester systems that generate and sell electricity.[36] However,  the amount of excess energy generated by digesters on smaller farms is generally insufficient to sell the energy back to the grid.[37] Because of this, it is not profitable for a smaller operation to construct or operate a digester to sell excess energy – profitability depends on the generation of a lot of manure and requires a lot of financing.[38]

Incentivizes CAFOs: Critics contend that the significant financial investment necessary and the large amount of manure required for manure-to-energy projects to be profitable only incentivizes CAFOs to get even bigger.[39] There is evidence to support this concern. With the installation of a biogas project, a dairy CAFO in California has applied to construct new facilities and expand its dairy herd to 9,000 cows – almost double its current number.[40] In Oregon – where hundreds of smaller dairy farms have ceased operations in the past several decades – Threemile Canyon Farms – which has a herd of around 70,000 cows at one CAFO – has enjoyed tax breaks and carbon credits through both an Oregon state program and California’s cap-and-trade market.[41] As such, some worry that the proliferation of manure-to-energy projects will further entrench industrial animal agriculture in the U.S., leading to a vicious circle of more animals, more manure, and more methane.[42]

Environmental justice concerns: Incentivization of CAFOs is especially problematic for environmental justice reasons. Studies have shown that CAFOs are disproportionately sited in areas with a large percentage of BIPOC (black, indigenous, and people of color) and/or low-income populations.[43] These communities already suffer from the deleterious environmental impacts of CAFOS, including noxious odors and gases.[44] Research indicates that individuals who live near CAFOs experience a variety of illnesses from exposure to malodorous compounds: higher incidence of respiratory and neurological disorder symptoms; greater risk of bacterial infections; mood disorders, including depression and anxiety; and disturbed sleep.[45] Manure-to-energy projects threaten to make this worse. A recent study found that the concentrations of “minor chemical and biological components in biogas could potentially be toxic to human health.[46] Furthermore, the pipelines and other infrastructure necessary for manure-to-energy projects will only bring more pollution into already burdened communities.[47]

In sum, communities with environmental justice concerns are troubled by the “transformation of CAFOS into combined factory farms and biogas facilities under the guise of ‘green energy.[48]

Enteric emissions: Furthermore, methane digesters do nothing to curb enteric methane emissions, which are emitted when a cow belches.[49] Cows are the highest methane emitting livestock because of the way they digest their food; these enteric methane emissions comprise a large portion of overall greenhouse gas emissions from the agricultural sector[50] – representing more than 25% of emissions from the agricultural sector, according to the EPA.[51] With or without manure-to-gas operations, enteric methane emissions will continue, and if CAFOs increase the number of animals they house because they are receiving biogas credits, enteric emissions will actually increase.[52]

Alternatives and policy recommendations.

Critics of manure-to-energy projects set forth a number of alternatives and policy recommendations. Overall, policies are needed that encourage sustainable farming and will assist smaller-scale, independent farmers “to thrive in a way that does not harm communities, the environment and public health.”[53] The following are just a few specific suggestions:


·         The federal government and the states  should adopt a moratorium on the construction of new CAFOs and the expansion of existing CAFOs.[54] The Farm System Reform Act (FRSA), reintroduced by U.S. Senator Cory Booker (D-NJ) in 2021, would do just that.[55] FRSA would also adopt a voluntary buyout program for to assist current CAFO owners to transition to more sustainable farming methods.[56]

·         The EPA should set limits on methane emissions from CAFOs under the Clean Air Act.[57]

·         More effective water and air pollution laws should be enacted and existing ones should be better enforced against CAFOs.[58]

·         CAFOs should be removed from EQIP eligibility. In 2020, 11% of EQIP funds went to CAFOs.[59] Similar action should be taken for the Conservation Stewardship Program.[60]

·         The Biden Methane Plan should reinstate National Environmental Policy y Act (NEPA) review requirements for guaranteed government loans for CAFOs. The Trump administration created an exemption for USDA and SBA loans for new and expanding CAFOs.[61]

Because less livestock would result in less manure, which would result in fewer methane emissions from livestock manure, the most effective of these suggestions for curbing methane emissions would be the adoption of moratoria on the construction of new CAFOs and the expansion of existing CAFOs. Incentives should also be provided to farmers to transition from livestock production to the sustainable farming of plant-based crops and for consumers to adopt plant-based diets.


The disadvantages of manure-to-energy projects far outweigh their advantages. Policies and incentives to encourage the adoption of sustainable farming of plant-based crops and discourage the proliferation of intensively-raised livestock would be far more effective at addressing the problem of methane emissions from livestock manure.



[1] Valerie Baron, Big Ag Is Hiding in Plain Sight & It’s Making Us Sick, NRDC (Sept. 23, 2019), https://www.nrdc.org/experts/valerie-baron/factory-farms-what-we-dont-know-hurting-communities.

[2] Carrie Hribar, Understanding Concentrated Animal Feeding Operations & Their Impact on Communities, NALBOH 2 (2010), https://www.cdc.gov/nceh/ehs/docs/understanding_cafos_nalboh.pdf.

[3] Id.

[4] Id.; Austen Dip, Why are CAFOs Bad for the Environment?, ACE (Aug. 6, 2021), https://acespace.org/2021/08/06/why-are-cafos-bad-for-the-environment/

[5] Hribar, supra note 1, at 2.

[6] Id. at 7. Manure management is also the fourth biggest source of nitrous oxide emissions. Id.

[7] Id.; Importance of Methane, EPA, https://www.epa.gov/gmi/importance-methane.

[8] See  Hard to Digest: Greenwashing Manure into Renewable Energy, Food & Water Watch (Nov. 2016), https://foodandwaterwatch.org/wp-content/uploads/2021/04/ib_1611_manure-digesters-web.pdf 17, (discussing the problems associated with manure digesters and why they have a negligible impact on reducing GHGs and other environmental impacts of industrial animal agriculture).

[9] Sierra Club, Sierra Club Guidance: Methane Digesters & Concentrated Animal Feeding Operation (CAFO) Waste, https://www.sierraclub.org/sites/www.sierraclub.org/files/methane_digesters.pdf; Georgina Gustin, As the Livestock Industry Touts Manure-to-Energy Projects, Environmentalists Cry ‘Greenwashing’, Inside Climate News (Dec. 7, 2020), https://insideclimatenews.org/news/07122020/livestock-industry-manure-energy-natural-gas/.

[10] Gustin, supra note 9.

[11] Id.

[12]  Id.

[13] Id.

[14] Tamara Dietrich, Dominion, Smithfield Foods Double Their Investment to Turn Pig Manure into Energy, Daily Press, Nov. 4, 2019, https://www.dailypress.com/business/dp-nw-pig-manure-methane-20191104-ar2mkv5cqrdvjlgrm32puop2bi-story.html; About Us, Align RNG, https://alignrng.com/about-us.aspx.

[15]  Gustin, supra note 9.

[16] Id.

[17] For a detailed look at the Biden Methane Plan, see White House Off. of Domestic Climate Pol’y,

U.S. Methane Emissions Reduction Action Plan  (Nov. 2021), https://www.whitehouse.gov/wp-content/uploads/2021/11/US-Methane-Emissions-Reduction-Action-Plan-1.pdf.

[18] Ben  Lilliston, Meeting the Methane Pledge: The U.S. Can do More on Agriculture, Inst. for Agric. & Trade Pol’y (June 2022), https://www.iatp.org/meeting-methane-pledge-us-can-do-more-agriculture.

[19]  Id.; for more information on USDA funding and incentives for manure-to-energy projects, see Laura Melling, USDA Offers Funding to Help Farmers Turn Manure into Energy, USDA (Feb. 21, 2017), https://www.usda.gov/media/blog/2010/11/18/usda-offers-funding-help-farmers-turn-manure-energy (providing links to more information on the new Conservation Loan program, the Rural Energy for America Program, the Value-Added Producer Grant, and the Environmental Quality Incentives Program).

[20] Leah Douglas, Biden Climate Law Could Expand Controversial Biogas Industry, Reuters (Aug. 19, 2022), https://www.reuters.com/legal/biden-climate-law-could-expand-controversial-biogas-industry-2022-08-19/.

[21] Lilliston, supra note 18.

[22] Id.

[23] Although beyond the scope of this blog post, there are also many animal welfare issues associated with CAFOs, as well as food safety concerns. Animal Factories & Animal Welfare, Ctr. for Food Safety, https://www.centerforfoodsafety.org/issues/307/animal-factories/animal-factories-and-animal-welfare.

[24]  Hard to Digest: Greenwashing Manure into Renewable Energy, supra note 8.

[25] Jenny  Splitter,  America Has a Manure Problem & the Miracle Solution Being Touted Isn’t All That It Seems, Guardian (Jan. 2022), https://www.theguardian.com/us-news/2022/jan/20/manure-natural-gas-pipeline-factory-farms-greenwashing.

[26] Fact Sheet | Biogas: Converting Waste to Energy, EESI (Oct. 3, 2017), https://www.eesi.org/papers/view/fact-sheet-biogasconverting-waste-to-energy; Benefits & Challenges of Manure-Based Energy, LPELC (Mar. 5, 2019), https://lpelc.org/benefits-and-challenges-of-manure-based-energy/.

[27] Phoebe  Gittelson et al., The False Promises of Biogas: Why Biogas Is an Environmental Justice Issue, Envtl. Just. (2021), https://www.liebertpub.com/doi/pdf/10.1089/env.2021.0025.

[28]  Id.; Hard to Digest: Greenwashing Manure into Renewable Energy, supra note 8.  

[29] Lilliston, supra note 18.

[30] Gittelson et al., supra note 27.

[31]  Splitter, supra note 25.

[32] Id.

[33] Erin Jordan, Anaerobic Digester Death Ruled Accidental Drowning, Gazette (July 28, 2021), https://www.thegazette.com/agriculture/anaerobic-digester-death-ruled-accidental-drowning/.

[34]  Jessica McKenzie, The Misbegotten Promise of Anaerobic Digesters, The Counter (Dec. 3, 2019), https://thecounter.org/misbegotten-promise-anaerobic-digesters-cafo/.

[35] Lilliston, supra note 18.

[36] Jenifer Beddoes, et al., An Analysis of Energy Production Costs from Anaerobic Digestion Systems on U.S. Livestock Production Facilities, Technical Note No. 1, USDA Natural Resources Conservation Service (Oct. 2007), https://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=22533.wba, at 1, 4, 14, 16; Hard to Digest: Greenwashing Manure into Renewable Energy, supra note 8. In contrast, manure digesters that use the biogas as an alternative to natural gas for heating needs directly on-farm may indeed be a viable option for farms. Id.

[37]  McKenzie, supra note 34.

[38] Id.

[39]  Lisa Held, Are Biogas Subsidies Benefiting the Largest Industrial Animal Farms?, Civil Eats (Sept. 20, 2021), https://civileats.com/2021/09/20/are-biogas-subsidies-benefiting-the-largest-industrial-animal-farms/.

[40]  Id.

[41] Id.

[42] Lilliston, supra note 18. It should be noted that land use restrictions may not be helpful in restricting the growth of CAFOs. Although some county and local governments have enacted zoning ordinances that impose limitations on CAFOs, these limitations may be preempted by state laws. CAFO Regulations, County Health Rankings & Roadmaps, https://www.countyhealthrankings.org/take-action-to-improve-health/what-works-for-health/strategies/cafo-regulations#footnote_6; Jennine Kottwitz & Tegan Jarchow, Concentrated Animal Feeding Operation (CAFO) Regulations, Sustainable Development Code, https://sustainablecitycode.org/brief/concentrated-animal-feeding-operation-cafo-regulations/.

[43] Gittelson et al., supra note 27.

[44] Id.

[45]  Id.

[46]  Id.

[47]  Id.

[48] Id.

[49]  Splitter, supra note 25.

[50] Id.

[51] Sources of Greenhouse Gas Emissions, EPA, https://www.epa.gov/ghgemissions/sources-greenhouse-gas-emissions.

[52] Although meat and dairy companies are undertaking research to develop feed additives and supplements – like seaweed – that inhibit bacteria formation in a cow’s rumen during the digestive process to reduce enteric methane emissions, these trials have been small in scale; on a larger scale, the feasibility of adding seaweed to a cows’ diets throughout their entire life cycles is questionable. Changing Markets Found., Blindspot: How Lack of Action on Livestock Methane Undermines Climate Targets 48 (Oct. 2021), http://changingmarkets.org/wp-content/uploads/2021/10/Blindspot_methane-English.pdf, Envtl. Investigation Agency &

Global All. for Incinerator Alts., Methane Matters: A Comprehensive Approach to Methane Mitigation 17 (Mar. 2022), http://changingmarkets.org/wp-content/uploads/2022/03/CM-WEB-FINAL-REPORT-METHANE-MATTERS-1-1.pdf; Jan Dutkiewicz & Matthew Hayek, Want Carbon-Neutral Cows? Algae Isn’t the Answer, Wired (Mar. 17, 2022), https://www.wired.com/story/carbon-neutral-cows-algae/.

[53]  Hard to Digest: Greenwashing Manure into Renewable Energy, supra note 8.

[54] Id.

[55] Booker Reintroduces Bill to Reform Farm System With Expanded Support From Farm, Labor, Environment, Public Health, Faith Based and Animal Welfare Groups, Cory Booker, https://www.booker.senate.gov/news/press/booker-reintroduces-bill-to-reform-farm-system-with-expanded-support-from-farm-labor-environment-public-health-faith-based-and-animal-welfare-groups. The Farm System Reform Act would also “strengthen the Packers & Stockyards Act to crack down on the monopolistic practices of meatpackers and corporate integrators… and restore mandatory country-of-origin labeling requirements.” Id.

[56]  Lilliston, supra note 18.

[57] Id.

[58] Hard to Digest: Greenwashing Manure into Renewable Energy, supra note 8.

[59]  Lilliston, supra note 18.

[60] Id.

[61] Id.