Hewlett-Packard released this week a research paper describing how a data center could be powered by the waste from a dairy farm. (Would that make it a 'green' data center, or a 'brown' one?)

"The HP ASME paper shows how a farm of 10,000 dairy cows could generate 1MW of electricity, enough to power a typical modern data center and still support other needs on the farm," the company described. "Heat generated by a data center could also be used to more efficiently process the animal waste and thus increase methane production."

HP also described a number of other aspects of the potential project:

  • "The average dairy cow produces about 55 kg (120 pounds) of manure per day, and approximately 20 metric tons per year – roughly equivalent to the weight of four adult elephants.
  • The manure that one dairy cow produces in a day can generate 3.0 kilowatt-hours (kWh) of electrical energy, which is enough to power television usage in three U.S. households per day.
  • A medium-sized dairy farm with 10,000 cows produces about 200,000 metric tons of manure per year. Approximately 70 percent of the energy in the methane generated via anaerobic digestion could be used for data center power and cooling, thus reducing the impact on natural resources.
  • Pollutants from unmanaged livestock waste degrade the environment and can lead to groundwater contamination and air pollution. Methane is 21 times more damaging to the environment than carbon dioxide, which means that in addition to being an inefficient use of energy, disposal of manure through flaring can result in steep greenhouse gas emission taxes.
  • In addition to benefiting the environment, using manure to generate power for data centers could provide financial benefit to farmers. HP researchers estimate that dairy farmers would break even in costs within the first two years of using a system like this and then earn roughly $2 million annually in revenue from selling waste-derived power to data center customers."

Such a system would also allow data centers to be built in rural areas rather than urban ones, which is good because cities are running out of space for them, reports an article in the New York Times. "The rise of higher-speed data transfer networks, however, has given technology companies a chance to move farther from large populations and still be able to get information to them as quickly as they need it," the article noted. "So companies like Google, Yahoo, Amazon.com and Microsoft have been engaged in a mad dash to find spots in the United States that have plenty of electricity and land. As a result, more data centers have been built in states like Washington, Texas, Iowa and Oklahoma. If those locations are near dairy farms, so much the better."

It would cost a dairy farmer about $5 million to purchase the equipment needed for the biogas system and $30,000 to run it each year, the Times quoted an HP researcher as saying.