This winter, manure from 400 Holstein cows will begin generating enough electricity to power 65 homes in the Willamette Valley. The manure will be stored above ground in "digester" tanks where, in heated, airtight conditions, bacteria produce gas in a few weeks. The methane is siphoned off to fuel generators that convert the gas into electricity.
The project is backed by a major Northwest utility, Portland General Electric. "If we don't build significant amounts of new generation over the next few years, what have been sporadic shortages will become chronic conditions," says company spokesman Joe Barra.
Although bio-gas will cost consumers a penny more per kilowatt-hour than gas-fired energy, Barra says in Oregon that won't be a problem.
"Environmental consciousness has risen to the point where people recognize the value of green energy and are willing to pay for it," says Barra. Because in Oregon low-interest loans and business energy tax credits are available, PGE expects to develop a product it can get on the ground without any out-of-pocket expense to the cows' owners.