What are we doing about dairy emissions? | A New Shade of Green | Sherry Listgarten | Almanac Online |

Local Blogs

A New Shade of Green

By Sherry Listgarten

E-mail Sherry Listgarten

About this blog: Climate change, despite its outsized impact on the planet, is still an abstract concept to many of us. That needs to change. My hope is that readers of this blog will develop a better understanding of how our climate is evolving a...  (More)

View all posts from Sherry Listgarten

What are we doing about dairy emissions?

Uploaded: May 30, 2021
I’m a big believer in each of us working to reduce our own emissions. But some things are harder than others, and for me I’m pretty stuck on dairy, and especially cheese. I’m not sure I even know how to eat a vegetarian meal without cheese.

Do we have to choose between dairy and a livable planet? (Photo credit: UC Davis)

I’ve been meaning to do a blog post on alternative dairy items, but I’m stalling because I’m just not that excited about trying them. Every now and then I’ll buy a few dairy-free foods in the hopes that we’ll give them a shot, but they stand idly by in our fridge until one of us checks an expiration date. Even the peach “almond milk yogurt” stands unopened right now, and that sounds pretty tasty, right? I am pretty sure the dried pseudo-cheese yeast flakes, or whatever that stuff is, would go unopened.

Our household has a dairy problem. And it’s not just us. Even though non-dairy milk is growing strong in the US, with per capita dairy milk consumption dropping 20% in the last ten years, cheese consumption has gone up 17% and butter 25%. When you look at overall dairy consumption on a milk-fat basis, it has gone up 8% since 2010. Yikes.

Milk consumption in the United States (blue) decreased 20% from 2010 to 2019, but overall dairy (maroon) went up 8% because consumption of high-fat cheese (orange) and butter (yellow) rose by 17% and 25%, respectively. (Source: USDA, 2020)

Maybe California lawmakers understood this when they set a goal in 2016 (SB 1383) to reduce methane emissions by 40% from 2013 levels by 2030. About one quarter of those emissions come from manure management and another quarter from “enteric fermentation” (burps).

Emissions from manure management and enteric fermentation (burps) compose more than half of all California’s methane emissions. Around 80% of those are from dairy farms. (Source: CARB, 2019).

California is putting its money where its goals are and has been investing hundreds of millions of dollars on programs to reduce methane. Farms are making headway. In fact, by some measures the improvements in greenhouse gas reductions on farms are some of the best bang for the buck that California is getting from its efforts to reduce greenhouse gases. Check out the table on pages 15-20 of the annual report on California’s climate investments of Cap-and-Trade funds. It shows the cost for removing a million tons of CO2e for each of the programs they have funded. Anaerobic digesters come out a big winner, costing only $9/MT CO2e. The digesters are being widely deployed, in part because farmers can reap carbon credits from reducing their emissions, and because they can use or sell the energy that is produced.

Manure management programs reduce emissions at a fairly low cost. To date, they have achieved 29% of all program reductions but used only 2.2% of the funds. (Source: CARB, 2021).

Thomas Perkins is the VP of Operations at CalBio, which designs and installs manure digesters at dairy farms. A digester covers a farm’s open waste lagoon to capture the emitted biogas, which is essentially methane. The gas can then be burned to generate electricity or to power vehicles. When asked during a recent CEC AgTech event how farmers respond to their sales pitch, he replied: “Dairies are eager to exercise our technology, they’re in a hurry for our digesters to be built quicker, sooner than later… (We hear) ‘Let’s get this thing started, and let’s start generating these revenues…’. The dairymen are out there ready for this improvement in greenhouse gas mitigation.” (1)

Biogas is virtually identical to methane and natural gas. It is subject to leaking from the digester or pipes just like natural gas, and it will produce carbon dioxide when burned, just like natural gas. Farms that use digesters need access to gas pipelines to export any methane that is produced. While many gas utilities are eager to incorporate this “renewable gas” for residential heating, it is relatively expensive and limited in supply, plus creates air pollution and emissions when leaked or burned. It is best used for sectors that are difficult to electrify, such as some industrial uses.

Because of these problems with biogas, California has also asked farms to reduce the amount of methane they generate by evaluating dry manure management techniques. When manure decomposes aerobically rather than anaerobically (in wet lagoons), much less methane is emitted. Composting waste is one way to do this. One innovative company, BioFiltro, uses worms to treat wastewater before it enters the lagoons (aka “vermifiltration”). Waste water is fed onto a deep bed of wood chips layered on top of crushed rock. As the fluid slowly seeps down through the 5-foot thick bed, worms living in the wood chip layer feed on the organics, removing 70-99% of contaminants from the liquid waste in just 4 hours, per BioFiltro’s VP of Marketing and Sales Mai Ann Healy. As a result, few organics are left to decompose in the lagoon.

When BioFiltro’s vermifiltration step is inserted before wastewater enters a lagoon, water quality greatly improves. The filtered water releases less methane and carbon dioxide, and is far more useful and easier to manage for the farms. (Source: EPIC AgTech Virtual Tour, 2021)

The higher quality water releases fewer emissions from the lagoon, and can be used for more purposes, such as cleaning out stalls or watering crops. The odor is also greatly reduced. Farms deploying this system can earn revenue from carbon credits, plus they can use or sell the worm casings (poop), which make for a great soil amendment. (2)

Greenhouse gas emissions from a wastewater lagoon are greatly reduced after being filtered through BioFiltro’s vermiculture system. (Source: Washington State University and BioFiltro, 2020)

While most dairy emissions stem from manure management, a smaller but still significant amount result from the cows’ digestion (fermentation) process. Researchers at UC Davis and elsewhere are investigating feed additives that can reduce the amount of methane that the cows produce. A small amount of red seaweed, for example, can inhibit the last stage of fermentation in the cow’s rumen so that they exhale hydrogen in place of some of the methane. Early experiments show a reduction in exhaled emissions of 33 to 80%, depending on what else the cows are eating. Seaweed can also improve the efficiency by which cows convert food to energy; they may need up to 20% less food on a seaweed-enhanced diet.

California’s dairy farms are under considerable pressure. Consumers want lower-impact dairy products, and the state aggressively regulates water quality, air quality, and animal welfare as well as climate emissions. On top of this, California has high costs for labor, energy, and permitting. Many smaller farms have struggled to make ends meet, leading to consolidation across the industry. Yet California is by far the largest dairy-producing state, supplying about 20% of the country’s milk, and over the years the dairies have become some of the greenest in the world. A UC Davis report estimates that California dairies have reduced emissions by 45% per unit of milk over the last 50 years. Professor Ermias Kebreab adds that others should take notice. “Attaining California’s level of production efficiency in all global dairy production regions could reduce total global GHG emissions by as much as 1.73 percent.”

These improvements don’t zero out the emissions from the cheese and other dairy I consume. I should still try out that almond-milk yogurt sitting in the fridge. But I do take some comfort in knowing that California’s dairy farmers are working closely with industry and academia to reduce their climate footprint and make this part of our food supply more sustainable. Straus Family Creamery founder and CEO Albert Straus says that he feeds the cows with an electric truck that is powered by the cows’ own digested waste. That is pretty neat. Moreover, it’s still early days for many of these technologies. Another presenter at the CEC’s AgTech event, CEO Sarah Richardson of MicroByre, talked about the potential to create designer microbes that transform waste into useful products beyond fertilizer, for example succinic acid or acrylic acid. She calls this “upcycling waste”. To what extent can we turn the dairy farmers’ biggest headache, the vast amounts of manure the cows generate on a daily basis, into a valuable new market for the dairies, while also reducing greenhouse gases and pollution? It’s a really interesting time to be a dairy farmer in California!

Notes and References
1. You won’t be surprised to learn that one of the biggest sources of delay is permitting. Managing large volumes of wastewater is no easy matter in California.

2. A dairy farmer discusses his experience with vermifiltration in this short video.

Current Climate Data (April 2021)
Global impacts, US impacts, CO2 metric, Climate dashboard (updated annually)

Comment Guidelines
I hope that your contributions will be an important part of this blog. To keep the discussion productive, please adhere to these guidelines or your comment may be moderated:
- Avoid disrespectful, disparaging, snide, angry, or ad hominem comments.
- Stay fact-based and refer to reputable sources.
- Stay on topic.
- In general, maintain this as a welcoming space for all readers.
What is it worth to you?


Posted by d page, a resident of Midtown,
on May 30, 2021 at 7:52 am

d page is a registered user.

In the first chapter of 'The Climate Diet', a new book by Paul Greenberg, there's a bar graph showing a variety of foods and how much CO2 is released by each. Lamb is the worst, then beef.

What I couldn't figure out is why cheese is considerably worse than yogurt or 2% milk. Do you have any idea about this? I couldn't find a reference link in the back of the book.

Thank you.

Posted by Sherry Listgarten, a Almanac Online blogger,
on May 30, 2021 at 12:20 pm

Sherry Listgarten is a registered user.

I got this email from a dairy farmer in New York:

Every dairy farm that fails in my beautiful green rain fed area of New York State turns into subdivision. This is bone grinding habitat large lot subdivision. We pay massive land taxes for the land each year. The land and the cows are the loves of our lives. We got no credit whatsoever for carbon sequestration, watershed protection, bio diversity in the good things that are produced on a dairy farm, along with a nutritious food that goes to New York City every day. In return urban journalist who know little about the land spit in our faces. I don’t see where you have the right to condemn dairy farmer. Enjoy your almond milk.

Posted by Sherry Listgarten, a Almanac Online blogger,
on May 30, 2021 at 12:26 pm

Sherry Listgarten is a registered user.

@dpage: It's just because it takes a lot of milk to make cheese. You need about 10 pounds of milk to make one pound of cheese. (And 20 pounds of milk to make one pound of butter.) In contrast, you need about one pound of milk to make one pound of yogurt.

Posted by Petra Karenter, a resident of Menlo Park: Downtown,
on May 30, 2021 at 2:50 pm

Petra Karenter is a registered user.

Ed note: Off-topic comment promoting climate denial removed.

Posted by David Coale, a resident of Barron Park,
on May 30, 2021 at 5:10 pm

David Coale is a registered user.

I used to eat a lot of dairy products especially cheese, but am now no longer, and better for it. What is heart healthy, is also cancer preventative, water wise and climate friendly and this is eating less or no dairy products. For milk substitutes there are lots of alternatives and some with more protein then milk, so this should not be a problem. As far as cheese goes, this is harder to find alternatives that melt the same way as cheese. I now buy Daiya products and this works for me, even in grilled cheese sandwiches and other dishes where melted cheese is called for. While not the same, the fourfold benefits more then make up for it for me. As for the ice cream, there are also lots of alternatives that work quite well. My favorite is So Delicious cashew milk Dark Chocolate Truffle frozen dessert. This also makes a really good chocolate ice cream martini that is to die for. So there are plenty of alternatives out there, you just have to keep looking and keep in the back of your mind the multiple benefits of eating less dairy and they will all taste better. That is what has worked for me.

Posted by Julian Gonzales, a resident of East Palo Alto,
on May 31, 2021 at 9:38 am

Julian Gonzales is a registered user.

[Post removed.]

Posted by Tyler Harris, a resident of another community,
on May 31, 2021 at 10:30 am

Tyler Harris is a registered user.

A pizza without cheese is not a pizza and the same applies to a cheeseburger.

America is not ready to fully embrace cauliflower crusts, boca burgers, and soy product substitutes.

And try telling the French to curtail their cheese-making industry or Wisconsinites.

A reduction in cheese manufacturing will not subside unless there is a decrease in demand.

Posted by Victor Bishop, a resident of Another Mountain View Neighborhood,
on May 31, 2021 at 10:31 am

Victor Bishop is a registered user.

No such thing as “non dairy milk". People can call almond/cashew water milk- but it is not milk.
I guess now dairy products are becoming the target of virtue signaling “environmentalists" in their zeal to force everyone to live the life they want to live

Posted by mikepat, a resident of Monta Loma,
on May 31, 2021 at 11:41 am

mikepat is a registered user.

I recently tied eliminating cottage cheese from my diet - I discovered that the probiotic's are important for my diet. It's nearly impossible to find a real non-diary probiotic.
Even the plant based probiotics are either iffy or contain traces of dairy.

Posted by Local Resident, a resident of Duveneck/St. Francis,
on May 31, 2021 at 3:28 pm

Local Resident is a registered user.

Exciting and interesting article! Thank you.

Posted by The Alternative Milk Man, a resident of another community,
on May 31, 2021 at 7:08 pm

The Alternative Milk Man is a registered user.

FYI...laboratory synthesized milk can easily replace dairy-based milk and is currently being marketed.

Since 2017.

Web Link

Posted by Jennifer, a resident of another community,
on Jun 1, 2021 at 9:17 am

Jennifer is a registered user.

I eat cheese and yogurt, and I drink milk occasionally. I've tried almond milk (Blue Diamond). Everything else is over the top, and I understand where the dairy farmer is coming from. Farmers and dairy farmers are very important to America.

Posted by Stepheny , a resident of Midtown,
on Jun 1, 2021 at 11:22 am

Stepheny is a registered user.

There are new studies which show that feeding seaweed to cows as part of their diet reduces their methane production: Web Link Please note the water it takes to grow just one almond -- 5 gallons by some estimates.

Posted by Fr0hickey, a resident of Old Palo Alto,
on Jun 1, 2021 at 12:14 pm

Fr0hickey is a registered user.

I eat meat.

Posted by Sherry Listgarten, a Almanac Online blogger,
on Jun 1, 2021 at 4:14 pm

Sherry Listgarten is a registered user.

Here is follow-up from the NY dairy farmer:

"Unfortunately, we are losing so many of the smaller and mid-sized farms that ecosystems are crashing. We can see this in the plummeting populations of grassland bird species, in habitats that have been eaten up for subdivision. As farmers, so many of us have worked decades, not because we thought we would get rich. All most of us want is to live on and protect the farmlands. Most of us will work incredible hours, forgo spending money on nonessential items, etc. and hope and pray that the next generation will keep the land safe instead of selling out for building lots. In other parts of the state that are not as wealthy, we just see mostly abandoned farmlands, miles of empty barns falling apart, fences falling down and empty pastures. There is a dynamic of hopelessness as well as some fairly dangerous disenfranchisement there."

I heard similar on an earlier blog post from some people in the midwest, where the younger generation was abandoning farmland and leasing the acreage for wind energy. There is a deep sense of trepidation and loss in areas that are facing so much disruption from climate change. Large-scale change and adaptation are not easy to work through.

Posted by Consider Your Options. , a resident of Another Palo Alto neighborhood,
on Jun 1, 2021 at 4:41 pm

Consider Your Options. is a registered user.

My family still eats cheese and ice cream, but much less of it. Though I buy less and serve smaller portions, I'm able to pay a little more for higher quality for tastier flavor experiences when I do buy these foods. I'm eating LOTS more veggies, and I'm getting pretty good at preparing them more creatively so I enjoy them more. I very rarely eat beef any more, But I still eat a little pork, poultry, eggs, or fish once or twice a day. My portions of these protein sources are MUCH smaller than they used to be.

My family is eating less overall, wasting less, and we are feeling better than ever. Moderation in all things seems to work for us.

I was fortunate to grow up near the beautiful family farms of Upstate NY. These beloved and carefully managed farms were a source of joy for nearby communities. They produced rich local foods, beautiful landscapes. Many family farmers were attentive caretakers of the land...and deeply interested in environmental issues. It saddens me to hear that culture is changing so.

Posted by Mondoman, a resident of Green Acres,
on Jun 4, 2021 at 12:02 am

Mondoman is a registered user.

Regarding the vermifiltration process and other similar pre-treating of the waste lagoon water, for a proper emissions comparison, don't we need to add together the emissions of both the treated water and the vermifiltration unit? Presumably the worms are also releasing CO2 (and maybe methane?).

Unless I'm missing something, it seems like biogas should burn quite cleanly, not emitting much other than CO2 and water. Thus, generating electricity or mechanical power out of burning it should be more valuable than the worm castings, without significant pollution issues.

Posted by Sherry Listgarten, a Almanac Online blogger,
on Jun 4, 2021 at 8:36 am

Sherry Listgarten is a registered user.

Mondoman: Thanks for the great question. I would say at a high level that the dry (e.g., vermifiltration) and wet (e.g., digester) approaches to manure management are different. One is not strictly better than the other. Many farms do both. (For dry, not vermifiltration so much yet, but various types of composting and stall management.)

Yes, you want to measure emissions from the whole system. I don't think worms emit methane, but you'd want to know how much of the CO2 and N2O or whatever is stabilized in the castings and soil vs emitted. You'd also want to pay attention to how the castings and soil are handled. I've only seen reports on influent/effluent from the bin, I think because they've focused so much on water quality.

Beyond that, you want to look at fugitive emissions (e.g., from pipes and digesters), at emissions from producing needed equipment (e.g., big steel bins), from hauling castings, purifying the biogas, etc. These are complicated and expensive analyses. I think some amount of this is needed to qualify for climate credits, but I'm not sure how in depth. Everyone wants the credits, so they do the analysis needed.

On top of that, farms don't look only at emissions and costs and credits. They look at operations overhead and also co-benefits, like soil quality, water quality, etc. I would emphasize that water management is a very big deal on farms, as it's highly regulated, both amount and quality. It is much easier to use and recycle clean water and castings than manure wastewater.

I've been watching some panels of farmers from a dairy summit, and the amount of things farmers have to worry about, particularly with climate change impacting temperatures, water, plant/animal health, and costs, is eye-opening. The right solution for manure management will depend on what problems a farm wants to solve and what constraints it has. Currently the digester approach has more momentum, I think in large part because of funding and support from gas companies. I don't think at this point there is a "best" way to manage manure.

Hope this helps some. Thanks for the great question.

Posted by Kiki, a resident of Old Mountain View,
on Jun 5, 2021 at 9:24 pm

Kiki is a registered user.

I think the dairy emissions are a drop in the bucket compared to other pollutants, plastic being the No. 1 Offender. Pay attention to all the plastic that you encounter each time you shop--and take each bit of plastic and try to recycle it. The single-use bags for fruits and vegetables, the packaging for pre-ready fruits & vegetables, the packaging for meat plus the bag you put over it so it doesn't drip, bread wrappings, the wrap of plastic around nearly everything we buy, the containers of everything from Pepto-Bismal to vitamins, the wrap around the pack of gum, the plastic covers for everything we buy, etc. It is endless. THIS is the major environmental destroyer of the planet, not dairies.

Follow this blogger.
Sign up to be notified of new posts by this blogger.



Post a comment

Sorry, but further commenting on this topic has been closed.

Stay informed.

Get the day's top headlines from Almanac Online sent to your inbox in the Express newsletter.

Backhaus in Burlingame finally opens for the holiday rush
By The Peninsula Foodist | 0 comments | 2,569 views

Fun Things to Do Around the Bay This Holiday – Peninsula Edition
By Laura Stec | 8 comments | 2,185 views

Burning just one "old style" light bulb can cost $150 or more per year
By Sherry Listgarten | 6 comments | 1,919 views

Banning the public from PA City Hall
By Diana Diamond | 19 comments | 1,533 views

My Holiday Wish List for Menlo Park
By Dana Hendrickson | 0 comments | 875 views


Support local families in need

Your contribution to the Holiday Fund will go directly to nonprofits supporting local families and children in need. Last year, Almanac readers and foundations contributed over $300,000.