Proposed facility to convert dairy methane to electricity

Desert Hills Dairy Biodigester, a Minden-based subsidiary of Carbon Bank Ireland Ltd., plans to construct a biodigester at Desert Hills Dairy in Wabuska that will use methane captured from cow effluent to generate electricity.

William D. McCann, chief executive officer and an investor in the project, says the dairy near Yerington was chosen because it yields large amounts of methane and because the facility can take advantage of favorable regulatory and business conditions of the Silver State.

"You get out from a digester what you put in, so we expect a high methane yield from this particular dairy, "McCann says. "We would not consider building a digester in California because the regulatory climate is not favorable to small businesses, and, in effect, a biodigester is a small business."

Construction of the project, dependent upon approval from NV Energy and the Public Utilities Commission of Nevada, is expected to begin in the second quarter of 2010. Construction could take as long as six months and employ between 15 and 20 tradesmen. Once constructed, the biodigester requires two people to run it and another five to 10 to process the fertilizer and synthetic mulch yielded from the biodigester.

The biodigester is expected to generate 9,630 megawatts per year. Desert Hills Dairy would use some of the power and would share in any proceeds from energy sold to NV Energy.

Cost for the project, McCann says, is roughly $5 million, with additional capital outlay for transformers and switching equipment to connect to the power grid. McCann says the biodigester is a way for dairymen to compensate for high operating costs that have eroded their profits in recent years.

"The biodigester allows a dairyman to offset the electrical costs of running his dairy, and it also allows him to offset his bedding costs," McCann says. "It also produces an additional stream of income, critical in this time when dairy income nationally is at an all-time low."

A biodigester converts organic waste, such as cow manure, into a nutrient-rich liquid fertilizer and biogas. The effluent leftover from gas production is an organic fertilizer that can be used on food crops.

Dairy cattle can produce huge amounts of methane gas, which has a greenhouse warming effect estimated at 21 to 23 times that of carbon dioxide. According to studies conducted at the University of Texas and statistics compiled from the Midwest Rural Energy Council, a herd of 10,000 cows can produce as much as a billion cubic feet of methane annually.