I was talking to a friend about Wisconsin, their insistence on coal-fired power plants, and how great dairy is when I wondered which produces more CO2, Wisconsin's cows or power plants? So I decided to do the math. Now, I must note that these numbers may not be perfect, only some brief research was included. Never-the-less, here is the math.
Numbers of Cows
1.26 m dairy cows
0.31 m beef cows
Carbon Impact of Cows by Protein
9 g CO2-Ceq per g protein dairy
62 g CO2-Ceq per g protein beef
Output of a Cow
2300 gal milk per cow per year
430 pounds beef per cow
Protein of Cow Outputs
128 g protein per gallon milk
~100 g protein per pound beef
Protein in Output of One Cow
294400 g protein of milk per cow per year
43000 g protein of beef per cow per year
Carbon Impact of Cow
2.649 m g CO2-Ceq per dairy cow per year
2.666 m g CO2-Ceq per beef cow
Carbon Impact of Wisconsin Cows
3.338 t g CO2-Ceq by dairy cows in Wisconsin per year
0.826 t g CO2-Ceq by beef cows in Wisconsin
4.165 t g CO2-Ceq by cows in Wisconsin
9.182 b lbs CO2 generated by cows in Wisconsin
Wisconsin Coal Production
2.241 m MWh electricity generated by coal in Wisconsin
2.241 b kWh electricity generated by coal in Wisconsin
Carbon Impact of Coal
2.21 lbs CO2 per kWh coal electricity
4.953 b lbs CO2 generated by coal in Wisconsin
1.854x more CO2 generated by cows than coal in Wisconsin
First, it was reaffirming that the carbon impact of a cow ended up being nearly the same whether the cow was used for dairy or beef production. I was impressed that the two ended up on the same order of magnitude and even more impressed that I was right.
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