US Efforts To Turn Farm Animal Poop into Biofuel Spark Concerns

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Yves here. As Lambert likes to say, I do try to keep up, but I must confess to being unfamiliar with this new farm to biofuel scheme. The fact that, at least per this article, these biofuel digesters are explosion-prone, can produce water contaminants, and also emit lung-damaging fumes is enough to raise questions as to whether this approach is a net positive.

By Shannon Kelleher. Originally published at The New Lede

Industrial-sized livestock operations have long been known for contaminating the environment and mistreating animals. Now, amid growing government incentives to turn the manure generated at these operations into climate-friendly biofuels, there are mounting concerns that the efforts could make industrial farming bigger and more dangerous.

Critics say government support for the production of biogas through the use of what are known as manure digesters comes with an array of well-documented risks. The digesters break down manure and capture methane gas, which can be used as fuel, but they come with a history of fires, explosions, hydrogen sulfide poisoning, methane leaks, and even drowning.

Methane digesters “exacerbate the dangers that are already endemic to industrial animal farming… where animals are housed in the same location as malfunctioning equipment, flammable liquids, and dangerous manure management practices,” said Alicia Prygoski, strategic legislative affairs manager at the Animal Legal Defense Fund (ALDF) animal advocacy group.

“Encouraging mass amounts of manure production, to facilitate the mass capture of the flammable gas that results from its decomposition, is what creates the increase in risks for explosions,” said Prygoski. “All you need is a spark.”

The Biden Administration’s much-touted Inflation Reduction Act includes funding and tax credits incentivizing farmers to install more of these digesters, and the new Farm Bill could include funds incentivizing the practice.

The ALDF and more than 100 other organizations sent a letter in December to US Agriculture Secretary Tom Vilsack calling on the agency to stop any allocation of additional funding from the IRA for the use or expansion of methane digesters or “production of factory farm gas.”

The groups cited a “ballooning factory farm gas industry,” and warned, among other issues, that digesters can “leak methane and manure and can even explode.”

Biogas on the Rise

Farms produce biogas using digesters – enclosed tanks in which bacteria and enzymes break down manure into methane gas, along with liquids and solids called “digestate”.  The waste, which contains concentrated forms of phosphorus and nitrogen, comes with its own risks as it is typically applied as fertilizer on farm fields where it can leach into – and pollute – waterways.

These systems have been applauded by the Biden administration as tools to cut methane emissions while converting animal waste into energy. Farmers can monetize the methane, which can be used for generating electricity or powering vehicles as compressed natural gas.

As of 2022, there were 331 biodigesters on hog, dairy, cattle and poultry farms. A study released in March by the US Department of Agriculture (USDA) says that, in the US, digesters have primarily been developed for and adopted by large farms (typically referred to as confined animal feeding operations, or CAFOs) with more than 1,000 animals. Large farms produce more energy with the technology and can expect better financial returns, the study says.

Biogas production on farms is “definitely increasing,” said Patrick Serfass, executive director of the American Biogas Council. “There’s a lot of interest in sustainability. A biogas system is almost always the top way to increase the sustainability of a farming operation, especially dairy or swine.”

To be sure, other risks beyond digester dangers loom large in industrialized livestock operations, critics say. And a major concern with rewarding farmers for the generation of manure that becomes biogas is the fear that the incentives encourage expansion of those already large hog, cattle, dairy and poultry farms.

With bigger farms and more manure come more health and environmental risks. Manure from CAFOs contains over 150 pathogens that can contaminate water, nitrates can cause dead zones in aquatic habitats, and harmful fumes can cause asthma and lung disease in people living near CAFOs, according to the National Resources Defense Council (NRDC). While CAFOs are regulated by the Environmental Protection Agency (EPA), their health threats are largely unmonitored, a 2019 NRDC report found.

Fire and Explosion Hazards

Fire and explosion are among the primary risks of biogas systems that rely on digesters, according to a  2021 report by BiogasWorld, an industry group that connects biogas suppliers and developers. The report mainly relies on data from Europe and looks at a variety of facilities that produce biogas, including farms and wastewater treatment plants.

The fires and explosions associated with the systems result mainly because of “inappropriate design or operation,” the report states.

A biogas that contains 60% methane is at risk of exploding if it is diluted 10% to 30% with air, according to a farm extension resource developed by US land grant universities and government agencies.

Fires within biogas systems may be caused by a number of issues, including gas leaks that result from corroded pipes or equipment failures, combustible materials onsite, electric fires, or blocked or frozen pipes, the BiogasWorld report states.

“With over 18,000 biogas facilities in Europe, just under 5% will experience some form of accident within their lifespan,” the report concludes. It finds that about 800 accidents (of all types) occurred on biogas plants in Europe between 2005 and 2015.

Dana Kirk, a digester researcher at Michigan State University, said the chance of a digester exploding “is really very minor” since the systems usually operate at low pressure.

“It really comes down to just following basic safety guidelines that are used in commercial and agricultural and industrial practices,” said Kirk.

Still, accidents do happen.

In 2014, an explosion at a farm in Dane County, Wisconsin blew the roof off a state-sponsored digester. Pipeline breaks from the same facility also caused three manures spills in three years, releasing more than 400,000 gallons of waste.

A biodigester in Lowell, Michigan ruptured from methane buildup and nearly exploded in 2016, resulting in citations from the state Department of Environmental Quality. In 2018, an explosion followed by a fire occurred at a farm in Saint-Fargeau, France, due to a faulty piece of digester equipment. Another digester caught fire at a Wisconsin dairy in 2020.

Accidents also occur at other types of facilities that use digesters. An explosion occurred at a wastewater treatment plant in Ontario, Canada that converts sewage sludge into fertilizer for agricultural fields in November 2020. And multiple biogas facilities suffered damage during storms in 2018 and 2019, releasing large quantities of biogas into the atmosphere, according to the BiogasWorld report.

Escalating Barn Fires

A massive explosion at the South Fork Dairy Farm in Dimmitt, Texas brought national attention to the barn fire issue, with a staggering 18,000 cows perishing in the blaze. The county sheriff said an overheated manure handling system may have ignited methane in the facility. The farm didn’t have a digester but was planning to install one.

US barn fires killed almost 3 million animals between 2018 and 2021, according to a report by the Animal Welfare Institute (AWI). The report included both traditional barns on small family farms and industrial confinement sheds on CAFOs.

“As we continue to see operations get larger and larger, the risks are going to continue to increase,” said Allie Granger, an AWI policy associate.

Beyond the potential for fires and explosions is the risk of leakage of hydrogen sulfide, a highly toxic, colorless gas that smells like rotten eggs, said Rebecca Wolf, a food policy analyst with non-governmental organization Food and Water Watch.

In 2005, a tank at a biogas plant that processed animal waste in Germany suffered a major hydrogen sulfide leak. A truck driver and three other workers died, while another worker was hospitalized, according to the BiogasWorld report.

In 2021, a contractor drowned in a digester tank that he was trying to repair in East Moline, Illinois. Officials said he was not wearing sufficient protective clothing or safety gear and the tank’s temperature may have been above the optimal range when the contractor entered it.

A “Manure Gold Rush”?

As lawmakers discuss priorities for the 2023 Farm Bill, groups opposed to digesters are wary that conservation and renewable energy programs will again include funding for them. The energy title in the 2018 Farm Bill grouped digesters together with solar and wind as energy projects incentivized by the USDA.

The incentives have already created a ‘manure gold rush’ by establishing revenue streams for the manufacture of liquid manure, according to the December 2022 letter from ALDF and other opponents. “These incentivize the further expansion and consolidation of the largest factory farms, which are already major polluters and sources of environmental injustice.”

In February 2021, Food and Water Watch and other groups filed a complaint to the Federal Trade Commission alleging that the pork-producing giant Smithfield Foods has been engaging in a “greenwashing” marketing campaign that “conveniently fails to recognize the hard realities behind its investment in digesters; this investment is designed to monetize its dangerous waste rather than solving the root problems of its unsustainable factory farm model and the waste management practices inherent in that model.”

The complaint alleges that Smithfield has planned to build numerous new CAFOs in Utah with the express purpose of capitalizing on digesters.

Serfass, who supports an expansion of the digesters, disputes the idea of a “manure gold rush.” Farmers expand their herd to achieve economies of scale and “create a reliable profit margin,” he said.

But Wolf disagrees.

“Digesters’ goal is to maximize output,” she said. “So not only are we generating methane but we’re looking to maximize it.”

“In reality what we need to be doing is taking a closer look at why are we generating so much methane in these huge liquid cesspools. By saying digesters do this wonderful environmental thing, you’re necessarily saying ‘and we want to keep factory farms around.’”

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  1. Henry Moon Pie

    It’s beginning to look like the Republican efforts to undo the so-called Inflation Reduction Act would not be that much of a negative for the Earth after all. We’ve already seen how that legislation pumps money to direct carbon capture, an oil company boondoggle that does more harm than good for the environment. Now there’s what’s probably a Big Ag boondoggle with biogas. Then there’s the whole thing with the EU being upset over subsidies provided to American companies that will hurt European industry.

    The IRA is just another Billionaire Bonanza Bill.

    1. Susan the other

      the rivalries are interesting. One of the best farming practices is to spread that poop all over the fields. Another, my fave, is purely French. Those irate farmers protesting government policies joined forces and drove their spreaders to Paris. What’s not to love? But rationally, this manure digestion has its niche. Not too big because it explodes big. – but smaller digesters which are manageable are an excellent idea. It’s an argument for small scale, but integrated complex farming. I can see that this could just as easily incentivize smaller livestock operations because to expand the herd in pursuit of “profits” is too pyrotechnic, and worse, all that poop profit would have the trade off that meat would become very cheap. Right?

      1. some guy

        CAFO manure bio-digesters appear to be another effort to pretend and extend CAFOs. And pretend and extend the GMO-Roundup system which feeds the CAFOs.

        1. some guy

          Also, a CAFO is not a farm and therefor CAFO animals are not farm animals. Confucius once said, ” First, we need a rectification of the language.”

    2. Scylla

      I work on farm infrastructure for a living. My personal beliefs are basically as follows.
      1. CAFOs are bad.
      They are not efficient (burn huge amounts of fuel to offset labor costs, and because they centralize animals- everything must be trucked to and from the animals), they pay low wages, the workers (due to the low wages) are not conscientious. Animal welfare is not good. Environmental stewardship is typically poor (this has been my experience with large crop operations not involving livestock as well). The cutoff for cows is right around 800 animals, depending on the herd average weight. 1000 animal units is the cutoff- anything above that and a farm is a CAFO. An animal unit is 1000 lbs of animal, regardless of the species.
      2. Smaller farms are generally more conscientious all the way around. They are more efficient in that they often pasture their animals- so instead of trucking feed to them, and trucking waste away, at least a portion of the time, the animal moves to the feed, and spreads it’s own manure. Small farms are better stewards (the owners do all of the work, so they take care of the farm and the animals better- as opposed to low wage employees).
      3. Livestock is essential to agriculture. A great many people can become vegans, but the animals are still essential to the nutrient cycle *especially if you believe we should reduce fossil fuel use, or that we will eventually face fossil fuel constraints*. It has been found that desertification is reduced, while topsoil retention, soil health, and plant health, are all increased when herds of ruminants are constantly being rotated across the land (in a structured manner that mimics ruminant migration/movement patterns from prehistory). If you accept the necessity of livestock, you must also accept the necessity of predation- and given that we have killed off all the natural predators, plus that we must move these animals across the land in a controlled manner to maintain crop agriculture, we humans (some of us at least) must accept the role of predators.
      4. Anything we can do to increase farm efficiency, capture and use byproducts, and balance energy used by the farm with energy that can be produced by the farm should be explored as much as possible. Inputs and outputs need to be balanced to whatever degree we can attain. Animal waste produces methane, hydrogen sulfide, and other products no matter what- especially if it is concentrated (even in relatively small amounts), so it seems foolish not to capture and make use of these. It is good practice to store animal waste as it cannot be spread on more mature actively growing crops, and it should never be spread on snow or frozen ground as it immediately washes into streams come spring. It should only be spread in the spring and fall- in both seasons when vegetation is actively growing to uptake the nutrients.It is also good practice to house animals on concrete when the ground is soft so that the animals do not damage the pasture itself (note that this practice is different than constantly keeping them on a feedlot year round), or subject the cows to unhealthy muddy conditions.

      All of this said, you do not have to have a CAFO to operate a digester. I know of one operation that keeps a digester filled with 400 milking cows. That is an above average sized farm, but it is not at all massive, and it is within the limits where good animal health and stewardship can be maintained. This digester is connected to a generator set and never produces less than 300 kw per hour- sometimes as high as 500 kw/hr, day-in, day-out, except for preventive maintenance shutdowns. Can it explode? Yes, but it is definitely no more likely to explode than tanks full of diesel or gasoline that are all over the place, and given that it is more diffuse and the area inside the digester is anearobic and very slightly pressurized (comparable to a hot air balloon envelope), an explosion is very unlikely unless the cover is catastrophically damaged and exposed to an open flame or spark- these facilities are typically located on a farm in the outermost fringes of farmstead/headquarters infrastructure- where they are less likely to be damaged, as well. I do not seem them as particularly dangerous. On this type of operation- the most dangerous thing is when stored liquid manure (common even on small dairies) is agitated prior to pumping out the storage- this produces hydrogen sulfide and in older farms where the storage is under the barn, this gas can be deadly as it displaces oxygen. The several drownings that I have heard about (3 in 15 years- in the northeast US) have occurred when someone tried to dump manure into these tanks from an improvised position, rather than the designated location. The machine tipped forward into the tank, trapping the operator-who then drowned/suffocated.
      There are a great number of problematic practices in modern agriculture, but I do not personally believe that digesters are one of them. One of the biggest problems IMO right now, is our propensity to use feedlots/CAFOs, where we are trucking food and manure back and forth (100s of miles in some cases), rather than letting animals simply walk. This would be far more efficient, and would result in better animal welfare, and better soil/plant health.
      I guess I’ve gone on enough, so I’ll stop there.

      1. Tedder

        Nicely put. In short, CAFO are the problem, not the methane. India at some point used methane digesters from animal and humans to produce cooking gas for the local area. No one ever reported any accidents or adverse effects, but these facilities were all small.
        Additionally, if the CAFO does not digest the manure, it sits in pools as hazardous waste, and as we have seen in floods, a major danger to the environment.
        Most important, the end products of digesters is not only methane gas, but valuable fertilizers absolutely necessary for soil and crop health.

  2. tevhatch

    China had quite a bit of experience with both small and large scale methane production, primarily from pig manure. Most of it went away as the electric power grid expanded. Knowing the CPC, there must be quite a lot of documentation on the real world positives and negatives, and what were the more useful outlets for manure that took over (such as feedstock for various aquiculture processes). I suspect rather than doing the legwork to gather up all this experience, this is a program run by MBAs to solve a political problem as cheaply as possible.

    “By saying digesters do this wonderful environmental thing, you’re necessarily saying ‘and we want to keep factory farms fast food, roasted chicken at Costco, etc. around.” Knowing the real issue is key.

    1. Rod

      imo, you are spot on with your observations.
      our arch enemy China does have the experience but we don’t talk. /s
      NC/SC are filled with Industrial Livestock operations that have been causing problems mentioned by our Host for decades with seemingly little care or solution. State Universities here are all over the Study Funding however. For Decades.
      Tweeks may be necessary, but they do it at my County Landfill 12 miles from this keyboard—ffs.
      Granted they just vent it into the atmosphere—lacking the imagination to even hook up a Generator like those Bit Coin Miners in Texas I linked to months ago–to power the Security Lights at the Transfer Station adjacent. You know.
      Like you, in AMERICA I see much of the issue MBA related–Go Big and Make Money or Forget About It.
      With those tweeks I mentioned and left undefined (-let the Engineer Readership shred–) I bet they could power their own Pole Lights along with a tractor or two.
      my worn out two cents
      I hope somebody comments and links to what the USA was doing for Power at the turn of the last century

      1. Rod

        One other thing,if I may.
        NC has been on top of this:
        In the Context of Matt Taibbi’s reporting since Twitter–and adjacent reports by real Journalists he has assembled, and comments by our Host’s to be sure— is the Article above:
        imo, a comment by Flora would be insightful i’m sure

  3. chuck roast

    The lady doth protest too much, methinks. When the next hurricane hits the middle Atlantic states and the tsunami of animal effluent cascades into the populated areas…yet again…this woman will probably take lunch. Industrial scale livestock farming and all of its attendant social and environmental problems needs to be addressed. But we all know that there are way too many rich folks sucking on this cash cow. Even small and medium sized farmers have a problem with animal effluent. Any good-faith effort to deal with this issue should be a socio-environmental plus.

    This is not a bogus high-tech environmental scam like ‘carbon-capture.’ Seems to me that this is relatively low-tech. Is our engineering really that bad? Maybe it’s like using constructed wetlands as a solution to human waste remediation…it’s just too cheap and easy and doesn’t lend itself to some high-priced, complex solution.

    1. vao

      The issues seem to result from large-scale digesters set up in industrial farms. More voluminous, more methane, more laborious to maintain, profit-seeking operators in a low-margin business cutting corners, higher risks.

      I remember to have seen documentaries on such installations for villages in India, and they were of course much smaller and did not look that threatening. The long running policy of installing digesters of swine manure in Chinese villages, as mentioned by tevhatch, is another case.

      But what boggles my mind is this:

      US barn fires killed almost 3 million animals between 2018 and 2021

      I have difficulty to imagine the sheer number of barn fires and the sheer number of animals dying in each of those fires. The article mentions one with 18000 cows dying, and I still cannot figure out the dimensions of the barn complex that could lead to such a slaughter. With 3 million dead animals in 3-4 years, it means that devastating fires of a comparable severity must have been recurring at a frightfully high frequency.

      1. gwb

        Right, the group Engineers Without Borders has been involved in a number of village-scale biogas projects in developing countries. I haven’t heard of any problems with those.

    2. IM Doc

      I live right next door to a very large grass-finished beef ranch. These are cows which are never fed corn, grass only.

      Every summer, my kids and I load up dozens/hundreds of cartloads of manure from the pastures and then compost them over the winter and into the spring. This is pure organic cow manure. They do not use antibiotics or any other excessive chemicals or hormones on these cattle as is done in the big lots.

      Cow manure is the champagne of fertilizer. There is absolutely nothing like it to provide nitrogen to our own fruit trees, berries, vegetables etc. And the ranchers are just ecstatic that we are doing this for them.

      This is back-breaking work. But so worth it in the food production it allows. I would never dream of touching an ounce of manure from one of these industrial style feed lots. The “manure compost” available in most nurseries is actually not cattle but human waste manure from sewage treatment plants. God only knows what all is in that. It is a very good way of filling your family with chemicals. And I am not sure what role the chemicals in the manure would play in the breakdown of this massive industrial type waste operation into biofuel.

      I am very happy to continue right on with what we do in our own world. Lots of hard work, but as my grandparents used to say – hard work never hurt anyone.

      Interestingly, the ranchers are no longer selling this beef to states like California, Illinois, and New York. The regulations and documentation has just become horrendous. They can simply not afford to do the paperwork. The meat is now headed to places like Texas and Florida. This is going on all over the heartland.

      1. PlutoniumKun

        Birds might disagree, they would insist that guano is the true gold standard of poo. The less efficient your stomach, the more nutrients get through.

        The value of manure is really dependent on timing and land type. Cow manure is a little less nutrient rich than pig manure as they have more efficient stomachs. But of course its easier to handle than pig manure, especially mixed with straw. It also makes a very fine cooking fuel, its widely used all over the Himalayan plateau.

        Apart from the scale of manure produced by modern farming, there is also a problem with timing. In climates with cold winters where animals have to be kept indoors you can have a huge build up in slatted sheds over the winter. Combine this with a wet spring and you have a problem, even with a low intensity organic set up. This is why digesters are very useful at ensuring there is no build up of excess and it has some use (the end material is not as good as aerobic compost, but its not terrible either).

        I’ve not seen figures on it, but my guess is that dairy cattle would have the most issues with manure contamination as they are more heavily injected with all sorts of things. Their food consumption will also be a problem – cattle can bioconcentrate whatever has fallen on the grass – this is the primary pathway for humans to ingest dioxins – via milk. With pigs, it largely depends on what they are fed. I’ve no idea in the US, but pig feed is very tightly controlled in Europe for just this reason. They aren’t even allowed use human food waste, which is a pity I think.

        But most sources get around the potential problem with all biowaste is that testing is only carried out in a very limited set of parameters. Regular testing for things like microplastics or drug residues or PFAS is rarely carried out. Pretty much every time land is tested for anything non-standard, there are some pretty scary results.

        The big problem is though that the more they find manure (including human manure) is unsuitable for use, the more likely it is to be incinerated, which is kind of the last resort.

        1. Nathan Hulick

          There is technology available (gasification) to deal with this waste already. It’s just that it’s cheaper to dump it in a landfill, burn it in an incinerator, or the preferred method, dump it onto a farm field.

          1. PlutoniumKun

            I think you are confusing different technologies. Biodigesters (or anaerobic digesters) generate gas – thats what they are. There is another process called gasification which is essentially a form of incineration (just in the absence of oxygen). Its rarely used for farm wastes as its quite expensive and produces a nasty sludge.

            1. Nathan Hulick

              I am not confused. Biodigesters produce a small amount of methane but most of the original sludge is left behind and then dumped onto farm fields. Additionally the resulting sludge is more toxic than originally

              The gasification technology is similar but much more efficient and the waste product is ash.

              Yes it’s more expensive which is why it isn’t used, but it destroys the toxic chemicals in the sludge and the waste can be used for stuff like cement additives.

              Unfortunately I know a ton about this topic after having 1 to 2 million gallons of toxic sewage sludge dumped onto a farm field next to my house a few years back.

        2. tevhatch

          Guano is the “gold(en) standard” :-) because birds mix their feces and urine together before passing, and the fecal material helps retain the urea molecule along with more complex nitrates. Seabirds have a diet especially high in nitrates, and they are pretty efficient at digesting most of it, but pass most of the nitrates, so their guano is the most fertile of all. Diet has a key impact on usefulness of manure. Terry Pratchett had a children’s story called Poo Sticks which is a fun introduction to the idea of many non-fertilizer applications, and which animals/diets prove fit for what purpose.

      2. thousand points of green

        One wonders how long the dung-pats persist on the surface of the pastures that they are still there to be harvested in summer. If these pastures had more dung beetles, would more of the dung be cycled right down into the soil itself for even better pasture growth? It could mean less dung for harvest but could mean better soil and more better pasture for more meat. Charles Walters wrote a book about dung beetles once.

        Could the regulations that ranchers like this are facing be a surreptitious government effort to disable their efforts to sell their meat to states like CA, IL, NY in order to reserve those markets for CAFO factory beef? Would those be state level regulations which some states impose but other states don’t? If they are Federal regulations, how can these ranchers’s pasture beef make it through the Federal embargo to Texas and Florida?

  4. doug

    Long ago, I visited a large hog operation in NC that had covered the open cesspool(called ‘lagoons’ by the industry) of hog waste with a rubber membrane and was piping the gas to a generator. They were all set to go online and sell the electricity. The electric coop(who was involved in this test case) just happened to drop the price of electricity to below the profit margin at the same time. I don’t think they wanted the competition.

    1. Billy

      This is a classic electric utility practice / scam in North Carolina.
      After all it is said that the Department of Administration building on Jones St. in Raleigh is owned by the electric utility.

      Any independent generating source be it wind, chicken manure, small hydro, biogas, wood waste, PV is immediately quashed by price manipulation sanctioned by the PUC. This has happened in Ashville with the city land fill (conveniently located next to the city sewage treatment facility, a excellent electrical load.)

      An discussion of power generation must have the understanding that the cost plus operational structure of power generation encourages the utilities to fiercely.protect their generating base.

      And remember the utilities do own the press.

  5. Eddie Mac

    As someone who lives quite near to a Missouri hog CAFO, and smells the repulsive odors of its open-air lagoons, barns and spray fields frequently, I say build ’em. As our governor, Republican-led legislature, and courts continue to demonstrate, this country is never going to rein in corporate ag. Therefore any remediation of the odors will be a welcome improvement to a terrible way of raising food.

    1. thousand points of green

      Then again, if only enough people would buy strictly and only grass-and-pasture fed beef and pork, the society could tear down and destroy the CAFO concept altogether, even in the teeth of a government devoted to protecting the CAFO concept on behalf of its Corporate owners.

      Pasture fed pork? is there such a thing?

  6. converger

    I’m sorry, this is just weird. Factory farming is bad. Collecting and using massive amounts of methane that’s getting blown out into the atmosphere right now anyway is harm reduction. They are separate issues.

    1. t

      Yep. Collecting massive amounts, as a thing, tend to be bad pretty quick with anything that is not 100% inert.

  7. PlutoniumKun

    Biodigestion is a long established and well proven technology. Its been around for many decades and there are thousands of them in place. Of course generating methane can be hazardous, but all sewage treatment plants (and pipes) generate methane as does any anoxic store of manure or other organic material. Even conventional slatted floor animal units (which are found not just on intensive farms) can have methane build up with fatal results – its one of the biggest causes of farming deaths. Biodigestors are almost certainly safer than the alternatives. Accidents involving them are very rare.

    Apart from incineration, the alternative to biodigestion is aerobic composting or landspreading. The former is difficult and likely to result in intense odours, and the latter is extremely polluting unless tightly controlled. Almost every study I’ve seen has concluded that anaerobic digestion is the safest and least environmentally harmful manner of dealing with large quantities of animal waste, and probably human waste too.

    The question isn’t whether we should be building them, the question is what is the overall alternative to intensive animal farming (it should be noted that animal wastes can be a hazard in non-intensive farms too, if the soil/waters are particularly sensitive). The problem is an addiction to cheap pork and chicken and dairy. Until we dramatically reduce the consumption of meat and dairy and enforce low intensive stocking practices (i.e. organic), we will need digestors.

    1. LY

      Yep. Need to rethink the whole meat production system.

      Problem is that meat, like cars, is what societies expect once they get richer. The Chinese government is sensitive to the price of pork (hence the efforts for diversification in imports of soy beans and corn), while the US governments made sure those slaughterhouses stayed open during the initial and deadliest COVID-19 wave.

    2. Nathan Hulick

      Biodigesters don’t get rid of all the waste, they just break down some of it. Generally you’re looking at a 50% reduction in the best case scenario.

      The remainder is often more toxic than the initial input and ends up getting spread onto farmlands just the same.

      Also as I mentioned in another comment, while these digesters are originally claimed to be for animal waste, in practice that’s not economically feasible and they end up using mostly sewage sludge and industrial waste as inputs rather than manure.

  8. Nathan Hulick

    I happen to be an expert on this toxic sludge, having been subjected to a few million gallons of it dumped onto a farm field next to my house a few years back.

    First off, while these digesters are marketed as to be used for animal manure, that isnt economically viable though and so what ends up happening is that after they are built the companies instead get paid more by sewer departments and industrial factories to dispose of their sewage sludge and industrial wastewater.

    The sludge factory that dumped 100 to 200 tractor trailers full of sludge next door to me and their cronies in the EPA originally claimed that it was 30% animal manure but after a few years of court battles and FOIA requests it turned out that it was about 0.0001% animal manure and the majority was sewage sludge, some of it from areas known to be heavily contaminated with toxic PFAS.

    There is absolutely no testing for any dangerous chemicals, the only required tests are for 8 heavy metals and common toxins. The EPA’s own inspector general reported a few years ago that there are at least 258 regulated toxic chemicals in this sludge but nobody is testing for them and the regulatory agencies work about as well as to be expected by any regular reader of nakedcapitalism.

    While this particular company received millions of dollars from US taxpayers in grants and loan guarantees, they actually produced only a negligible amount of electricity. I obtained their financial statements in a FOIA and the revenue from electricity sales was less than 10%. The vast majority was what are called “tipping fees”, aka the money paid to them to dispose of the sludge.

    Additionally, this company did not account for the liability of the 100 million gallons of toxic sludge they currently had stored in lagoons on the balance sheet, and if/when they are finally shut down the local residents can look forward to paying for the inevitable cleanup and/or suffering the environmental degradation that results from these toxic dumps.

    This company was very poorly run and their digester has blown up at least once, resulting in a young worker getting 3rd degree burns to his face. He was fired a few weeks later. The company didnt even bother to rebuild the part of the factory that produces methane, as it would cost way more to fix than they would get from electricity sales so for the last few years they just burn off the methane with giant vent that sounds like a jet engine when its running.

    Also they figured out that they could make more money just dumping the sludge into lagoons and illegally dumping it on nearby farms rather than going to all the trouble to run it though their digester. Despite literally thousands of local citizens complaining, filing lawsuits, etc, the EPA just continues to rubber stamp their permits and act more as a PR company for the sludge dumpers rather than a regulatory agency.

    For anyone unlucky enough to find out one of these sludge dumps is going to be built nearby, my advice is to sell your property as quickly as possible to the next sucker and not waste your time and money trying to get government agencies to enforce the laws these companies break regularly.

    1. some guy

      If one wants the EPA to “do better” , one would have to scrape out all the Republican embeds infesting it and all the Republican commissars dominating it from back to the Reagan period. One would need a strictly pre-Reagan EPA to get pre-Reagan-quality protection enforcement.

      1. Nathan Hulick

        That’s a common belief. However, it was the Democratic party under Strickland and with the help of Sherrod Brown who brought the current sludge industry to Ohio.

        Sherrod Brown, the alleged environmentalist, happily continues taking donations from these sludge companies and has been trying desperately for years to get more government money to them.

        I along with some other people met with his office a few years ago and got blown off.

        So, while it would be nice if voting in some democrats would change things, in practice it’s not as simple as that.

        1. some guy

          Well, we would have to raise a whole new generation of New Deal Social Democrats, either in the DemParty or outside of it in a party of their own.

          Its good to know about the Sherrod-Dems’ involvement in this particular sludge transplant.

          Still, earlier in your comment you discussed how the EPA gives pass after pass to deadly chemicals in general in sewage sludge in general, wherever it is in the country. And that approach was brought into EPA and other departments and agencies starting as far back as Reagan. And those agencies . . . EPA and the others . . . would have to be overtly and specifically de-republicantaminated of all the pro-pollution agents and embeds and left-behinds along with their anti-regulatory and anti-protectionary culture.

  9. LY

    This is part of the world building in Mad Max Beyond Thunderdome. Tina Turner’s character runs Bartertown, and Mad Max is pulled into the conflict with Underworld, which provides the energy via hog waste methane.

    I think the problems are solvable – engineers already manage similar risks in wastewater treatment plants (hydrogen sulfide) and natural gas plants. But, the intention must be sanitation and the environment first. Priority should be clean up *hit, then biogas.

  10. Amfortas the hippie

    i’m something of a lay evangelist for sewergas.
    “Natural Gas” is a marketing term.
    the issue…the real issue…here, is scale…as in Industrial Farming(sic)…not methane digesters.
    the only reason i have a dry composting toilet rather than a methane digester, is skillset.
    i intuited that my gashandling skills were not up to snuff to attempt it.
    add to that the fact that the folks around here who have adequate gashandling knowledge and skills universally scoffed at the idea…so no help, at all.
    its a rather simple process, and could be a boon to small operations like me.
    years ago, while researching this sort of thing for building the house, i ended up calling the EPA division who handles this specific thing: 2 guys…one who was always in china and africa, setting these up.
    the other guy, left at home to sit by the phone, was helpful, and excited to talk to an american interested in all this.
    turns out at the time, there were 2 companies in the USA who made small systems(ie: under $10k—most systems were goinf for a million $ or more)…both of them were forbidden by us law from selling such systems domestically.
    dude told me i’d hafta buy one from China…which had been made in Georgia, USA,lol.
    every landfill and sewer plant produces gobs of methane.
    capture it, run it through a carbon filter(charcoal) to remove the sulfur etc that makes it stink, and you end up with “Natural Gas” that would otherwise be simply vented to the atmosphere.
    remove the Market from the equation, and its a win win.
    as safe or safer than all the propane infrastructure…let alone the oil/gas/chem pipe farms scattered all over the coasts(see: Pasadena, tx)
    (the safety mechanisms were where my efforts ran into a wall…pressure relief, overheating release valves, etc)

    based on the source(something something animal rights, etc) the real issue that needs to be addressed is Industrial Ag, CAFO’s and the like.
    piss on Earl Butz’ grave and lets do something else besides continuing to pump billions of dollars into corporate agriculture welfare programs.
    i’ll also note that i will be unable to access any of the largess for this sort of thing included in the Farm Bill…i’m too small, off grid, and essentially a black market farmer…because the system, as it stands, makes my legitimate entrance into the white market impossible.
    Know Yer Farmer.
    and Jeffersonian Yeoman Farmers, like me, will be the salvation of a lot of us.

    1. some guy

      One wonders if enough people knew about that law forbidding the methane-digester maker you reference from selling his digesters in the very country where they are made; might they form a movement to get that law repealed?

      1. Amfortas the hippie

        if the Machine wants to push us to innovate in the shadows, so be it.
        the better to formulate and construct parallel institutions from the inevitable individual/small-collective efforts at workaround.
        “the West wasn’t won with a registered gun” and all.

        and if ya wanna get all radical(“of the root”):

    2. Stillfeelinthebern

      When I was in graduate school – science ed (1980s), another student who had spent 2 yrs in the peace corp tried a very small scale manure digester. It blew up and that was the end of that.

  11. KCM

    A study recently published and authored by Lorne Stockman director of Oil Change International is maybe somewhat tangential but overall germane to the above topic. The study lays-out how the oil & gas industry is turning to unproven and unregulated “gas certifiers” like Project Canary that claim to “measure” emissions and label there methane gas as “responsibly sourced”. The certified gas industry allows companies to charge a premium for their products, and have helped reverse the trend of investors shying away from new gas projects, including LNG buildout, claiming their gas is “clean.”

  12. Stillfeelinthebern

    I know an operator who started in 2021 to put in a digester and it was because of California’s carbon credits. He double the number of cows he milks from 1200 to 2400. He just finished about 3 months ago. He also told me it was his estimate that about a billion dollars total of these types of projects were in process in Wisconsin. I’m not sure how the methane gets into the pipeline. I know they are not producing electricity. Here is an article.

    Our local sewage treatment plant collects the methane and uses it to create electricity for their operations. Also, the spreading of the sludge that comes from that plant is strictly regulated and recorded. Municipal sludge is much more diverse than cow poop, think about it, not only the variety of things coming from homes, but industry. In Wisconsin, most farms will not take it.

  13. Revenant

    Where to begin?

    As Amfortas and others say, the problem here is factory farming, not biogasification. Factory farming leads to:
    – inappropriate nutrient release and eutrophication of water,
    – use of prophylactic antibiotics creating antibiotic resistance, to ivermectin and other anti-helminthics which make “plastic” cowpats which do not degrade quickly and naturally because they are toxic to invertebrates like dung beetles,
    – the wholly unnatural practice of feeding cows on grain as they were chickens rather than on pasture (a cow is nature’s biodigesters – a cow is nourished by the secretions and break-down of the bacteria fermenting her cud, not from any nutritive content of the grass itself, and a grain-fed cow is fermenting plant starches and passes noxious liquid faeces rather than healthy cow pats).

    Biodigesters are simple technology and do not pose risks to the community, any more than petrol stations or sewage plants. If biodigesters are a problem, it is because they represent an end-of-pipe solution to a polluting practice. Ideally, we would change the practice of intensive mono-culture farming into, for example, extensive mixed farming, so that arable fields feel the healing touch of the golden hoof, i.e. a rotational grazing system that fertilises them and improves soil carbon and organic content and moisture retention etc. But, while we work through that transition, digesters provide a valuable solution to excess slurry, compared to spreading it on fields in winter where it runs off into the rivers and kills them.

    In Northern Ireland there are intensive cattle operations where the slurry is continuously run out of the barns on permanent hoses and left to seep into the hillsides, making life unliveable for the neighbours because of the smell of ammonia and hydrogen sulphide and faeces. These neighbours would much rather live next to a digester!

    In the UK, there was one digester taking slurry from farms regionally, in Holsworthy, and it was built with grants as a demonstration project to show how slurry problems could be mitigated. After a few years, it was acquired by private equity and they repurposed it, like so many anaerobic digesters, into digesting food waste. The “gate fee” on disposing of tankers full of waste from the food industry is much higher than on slurry and the profit margin on the gas produced and used for electricity cogeneration is the same. There is no commercial biogas digester in the UK taking slurry. Several large dairy farms have private digesters though.

    I know a lot about this because a close family member is in charge of regulation and enforcement of slurry regulation in the UK!

    At the moment, initiatives to reduce the pollution from slurry include:
    – technical projects to make slurry more tradeable between the wet west where the cows are raised on grass and the dry east where the row crops need fertilising. One of the problems is that slurry is heavy to transport because of all the water. Keeping water out of slurry pits with covers for slurry pits and farmyards is a big programme, as well as proposals for dewatering, digestion to fertilising sludge etc. are all being examined. People have even suggested a pipeline!
    – encouraging farmyard manure and other bedding / housing systems and composting / digestion (where cow faeces are absorbed onto bedding like straw, rather than collected as liquid slurry from cows kept on slatted floors or concrete floors that are scraped). Farmyard manure is much more pleasant to handle and already has an inclusion of “browns” (the carbon in the straw) along with the “greens” (the high nitrogen slurry) to aid proper composting. Outwintering cattle removes any need for dealing with concentrated faeces because they remain on the pasture all year but the stocking density needs to be one cow every 8 acres rather than every acre in the winter, if you are to minimise poaching the land and destroying the pasture.
    – encouraging integrated farming, where the grazing of cows and other ruminants is brought back into arable farming, the golden hoof etc.
    – cutting herd sizes. Get big or get out has been the theme in the UK dairy industry because margins are razor thin because of supermarket oligopsony and capital investment costs and labour costs are high. The Dutch are being most radical, buying out farmers in order to reduce the excess nutrient input from intensive dairy farming. In the UK, the hope is that linking subsidies to environmental goods like clean water will enable farmers to farm at lower herd sizes in a new equilibrium. Not sure that it will work if we just import our milk from the Netherlands!

    1. PlutoniumKun

      Yup, its a very complex problem, and as you say biodigesters are not the problem, its the farming system. But its not just agriculture, human slurry is a massive issue and its becoming increasingly difficult to use it for farming (its far more widely used than most city slickers realise, its usually labelled ‘biosolids’ and mixed with lime).

      Unfortunately, intensification can be a creeping process, step by step a traditional farm keeps using ‘modern’ systems to increase productivity, and you end up with high intensive systems almost by default. A common thing here in the south is that as farmers retire they rent their land to the most ambitious local operator, who then centralises everything into a huge animal unit.

      Then of course when the problems become apparent, its someone elses fault and we end up with tech solutions. And agribusiness is increasingly good at using PR to pretend that policies to address it are ‘attacks on poor farmers and local communities’. We’ve seen this in the Netherlands where even leftists have been conned into supporting agribusiness at the expense of smaller operators.

      A few weeks ago I was visiting an elderly old school shepherd friend in the Wicklow hills. His sheep are not exactly environmentally friendly, but he tries to keep stocks down to minimise damage and he keeps a small number of beef cattle ‘because he likes the company’. He pointed to his neighbours field, an impeccably bright green among the darker wet fields and heather elsewhere. ‘Not a worm alive in that field’ he said. It was used for dairy (wildly inappropriate in the uplands) and is within 200 metres of a reservoir.

  14. Hayek's Heelbiter

    I have managed to go most of my life without reflecting on the topic at hand, so only read the article this morning.
    I have a friend of friend coming into town next week and needed to take a look at his film before we met for coffee.
    As it turns out, he was Peter Byck (Carbonation), Professor of Practice – Arizona State University School of Sustainability.
    He has recently completed a docu-series, Roots So Deep (You Can See the Devil Down There). I’d never heard the term adaptive (regenerative) grazing but there seems to be a huge amount of overlap between his scientific research and the issues raised by the article.
    Money quote (one of many) from the trailer.
    T*rds don’t just go away. There isn’t a magical T*rd Fairy who waves her magic wand, and they go away.
    Peter is affable and engaging, and as he says, “more interested in finding common ground” than assigning blame.
    You can watch the trailer at:
    And listen to an interview at:
    Highly recommended for anyone interested in this topic.

  15. Hayek's Heelbiter

    I have managed to go most of my life without reflecting on the topic at hand, so only read the article this morning.
    I have a friend of friend coming into town next week and needed to take a look at his film before we met for coffee.
    As it turns out, he was Peter Byck (Carbonation), Professor of Practice – Arizona State University School of Sustainability.
    He has recently completed a docu-series, Roots So Deep (You Can See the Devil Down There). I’d never heard the term adaptive (regenerative) grazing but there seems to be a huge amount of overlap between his scientific research and the issues raised by the article.
    Money quote (one of many) from the trailer.

    T*rds don’t just go away. There isn’t a magical T*rd Fairy who waves her magic wand, and they go away.

    Peter is affable and engaging, and as he says, “more interested in finding common ground” than assigning blame.
    You can watch the trailer at:
    And listen to an interview at:
    Highly recommended for anyone interested in this topic.


    1. Revenant

      Thank you for this link. I will show it to the family member. The Turd Fairy can join the Golden Hoof in our menagerie of regenerative agri-argot. I will get them to trot it out to the Minister. :-)

  16. thousand points of green

    Using earthworms to manage barn poop?

    Decades ago there was a book called Harnessing The Earthworm ( by Thomas J. Barrett). One of its chapters was about the possibility of using earthworms to manage barnload quantities of livestock manure. That chapter even gave a detailed example of a particular historical farm which was known to have used earthworms successfully to manage its barnloads of cattle manure. This was a farm, not a CAFO. Still, it was a real farm with real quantities of barnpoop to deal with.

    The possibility of using earthworms to manage manure is introduced in . .Chapter 5, A New Concept.
    The historical example of the farm which did this is described in . . . Chapter 6, Earthworms in General Farming ( ” My Grandfather’s Earthworm Farm” as told by Dr. George Sheffield Oliver.

    Here is the pdf of the whole book with screen shots of each page stacked vertically down a long scrollable screen.

    Again, this was a farm, not a CAFO. I don’t know how much bigger an operation this concept could scale to. On the other hand, this approach might be a powerful soil-building weapon in the hands of small real legitimate farmers today.

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