Sunday, February 8, 2009

Cow/Butterfly effect???

Probably many of us have heard about the “butterfly effect”. In sum, the butterfly effect is represented by “Small variations of the initial condition of a dynamical system may produce large variations in the long term behavior of the system” (Wikipedia). It seems that recently the Environmental Protection Agency was considering a tax on methane emanated from cows. This makes me wonder if methane emanated from a living animal like a Cow would contribute to, let’s say, Global Warming?

This week Kate Galbraith who writes for the NYTimes Blog on Energy brought up this interesting news. According to the E.P.A., due to their slow digestive system, cows’ methane is emitted when they burp and waste, and is 20 times more potent as a heat-trapping greenhouse gas than carbon dioxide. In the state of New York, this “Cow Tax” caused nonconformity among ranchers and farmers who pointed out that their cows do not contribute significantly to greenhouse gases. In round numbers the New York Farm Bureau (NYFB) calculated the tax for dairy cows could be $175 per cow, and $87.50 per head of beef cattle. The tax on hogs would upwards of $20 per hog. Any operation with more than 25 dairy cows, 50 beef cattle or 200 hogs would have to obtain permits (NYFB -Pdf Document).

“Farm animals simply don’t contribute greenhouse gases into the atmosphere at a higher rate than any other living thing. However, in this case, farmers would be forced to gain a permit,” said NYFB President Lincoln. He also mentioned “If you place these requirements on New York farmers, you will make it virtually impossible to run a viable farm operation. Then, unregulated, large agriculture from China and other countries will step in to fill the void. Regulating New York farms without addressing equal emissions in China and other nations will do little to address the global issue, and only penalize the New York producer.” concluded.

At the same time, farmers from the states of Texas and Alabama raised their concerns concluding that this “Cow tax” is not acceptable for the sake of the national agriculture.

I found another interesting article from Katie Zezima in the NYTimes who talks about how people who see cow-waste as a source of bio-energy denominated Cow-power. As an example, Green Mountain Dairy Farm (GMDF) is a farm in Vermont who is part of a growing alternative energy program that converts the methane gas from cow manure into electricity that is sold to the power utility’s grid. Four Vermont dairy farms are producing electricity for the utility, and two more are expected to be online by year’s end. The utility hopes to add six more farms by 2010. According to Katie “Residents and businesses that get their electricity from the program pay a premium of 4 cents a kilowatt hour above the typical rate of 12.5 cents. Most of that money goes to the farmers, who must purchase their own equipment, which can run up to $2 million per farm. Most farmers expect to make back their investment in 7 to 10 years.”.

The way it works is simple: The GMDF cows live in a “barn where a mechanical scraper sweeps the animals’ waste into a large drain. The waste is then pumped into a huge sealed concrete tank known as a digester, which holds 21 days’ worth of waste and is kept at a temperature of 101 degrees Fahrenheit. Anaerobic bacteria break down the organic matter in the waste, producing a mix of methane and other gases, known as bio-gas. The gas is burned in an engine that runs an electrical generator. “(Katie Zezima)

The cow waste produces 250 to 300 kilowatts of electricity daily, enough to power 300 to 350 homes, according to the utility. In addition, the farm processes about 500,000 gallons of waste and outdated ice cream from Ben & Jerry’s each year and puts it in the digester. The free ice cream, which the company drops off, helps the GMDF generate more electricity and saves Ben & Jerry’s the cost of disposing of it. “We’re improving our processes, and they’re improving theirs,” Mr. Rowell said. (Katie Zezima)

As shown previously, there are new technologies that cattle farmers are incorporating into their production. They have discovered that methane produced from their cows could possibly generate a good revenue for them and at the same time contribute with the reduction of greenhouse gas.







Kathryn Alexander said...

I found the NY times article by Katie Zezima especially interesting. The idea of turning animal and human waste into usable energy is not a new one, especially in developing countries. Small-scale methane “generators” exist all over the developing world, and are becoming increasingly popular as traditional fuels like wood are becoming more scarce. They are actually quite simple and require almost zero maintenance – cow manure (plus a little water) is put into an airtight container and a pipe sticking out of the top collects the methane produced. The methane can then be burned in cook stoves. This provides a number of advantages to traditional cooking methods including reducing the amount of time people (mostly women) have to spend collecting a fuel sources, reducing indoor air pollution, and producing a valuable organic fertilizer as a by-product.

It is interesting that Green Mountain Dairy Farm and others have taken a similar approach, burning methane produced from their cows’ waste to run a generator and produce electricity. In fact, methane is produced from rotting organic material and could be captured from a number of sources, including kitchen waste and landfills. Along with agricultural industries, landfills and the sanitation sector have the opportunity to recycle their organic waste, while making money by selling the resulting electricity to the power utility’s grid. Perhaps we will start seeing other industries follow Green Mountain Dairy Farm.

Anonymous said...

Great topic. Here's a great video about it... :)