User:Oliveleaf4/sandbox

Dairy production and methane emissions
United States

The Innovation Center for US Dairy has estimated that U.S. dairy accounts for 2 percent of total U.S. greenhouse gas (GHG) emissions, and is submitting its data set to the LCA Digital Commons of the National Agriculture Library." The EPA has also issued estimates of methane emissions from dairy cattle.

US livestock emissions are primarily from cattle and pigs.

Cows emit methane when they belch or burp.

The mechanisms by which cattle emit methane of concern for climate change vary.

Anaerobic digesters
There were 248 anaerobic digester projects operating on livestock farms in the United States in 2019, helping to reduce greenhouse gas emissions from methane.

Anaerobic digesters are technically feasible at more than 2,600 U.S. dairy operations, but only 176 manure-based digester systems had been implemented on farms as of 2012. California had more than 20 operating digesters in 2018, with about 20 more funded or under construction.

Manure mangement
Manure management is also an important strategy for emissions reduction.

Increased production to reduce emissions per unit produced
Increased production per cow is one way reduce the amount of methane emitted per gallon of milk.

While an average adult dairy cow can emit "400-500 liters of methane in a single day," the emission of an average Holstein dairy cow can vary between "¾ to over 1 pound (373 to 509 grams) of enteric methane per day depending upon the level of milk production."

Muzzles for cows
A device under development in England in 2020 aims to capture methane by placing a muzzle on the cow's nose, which converts the methane into carbon dioxide and water.

Improving feedstocks 

Higher quality forages and feedstocks improve digestability.

Additions to feedstocks include:


 * Mootral  
 * Seaweed
 * Asparagopsis taxiformis
 * Asparagopsis armata
 * Supplemental fats
 * Condensed tannin from black wattle (Acacia mearnsii)
 * Supplements to improve production, Monensin

California as a model for the US

"California dairies could produce enough biomethane to power more than 100,000 vehicles."

California's Dairy Digester Research and Development Program (DDRDP) and the Alternative Manure Management Program (AMMP).

The goal is reduction of greenhouse gas emissions from manure on California dairy farms.

Since 2015, 213 dairy families in California have been involved in DDRDP and AMMP projects. The projects reduce an estimated 2.2 million metric tons of greenhouse gases (2.2 MMTCO2e) per year. This is equivalent to removing more 460,000 cars from the road. The reduction is is approximately 25 percent of the 2013 California inventory for dairy and livestock manure methane emissions. The financing comes from a statewide initiative, California Climate Investments. The initiative uses Cap-and-Trade program funds to support the state’s climate goals.

Uses of biogas

Development of digesters that can inject utility-grade methane into natural gas pipelines, also run electrical generators

"Approximately 90 megawatts (MW) of power can be generated from Arizona manure."

Use as transportation fuel can prevent diesel emissions, "which can be some of the most toxic emissions that are put into the air in the San Joaquin Valley"