Posted: Thursday, August 26, 2010 9:00 AM
Concrete workers build the walls of a dairy digester just west of Lynden, Wash.
Company plans Tillamook operation
By STEVE BROWN
LYNDEN, Wash. -- What is now a hole in the ground will be a dairy digester churning out electrical power by late November, if not earlier, its builders say.
Kevin Maas said the dairy digester near Lynden is expected to be as much as 75 percent efficient in producing energy from manure. In addition to producing electricity, the digester's waste heat will warm a greenhouse.
"This is the first project to send its waste heat to a greenhouse," he said. "It should save the owner about $40,000 a year in heating costs."
The Lynden project is the second digester built by Farm Power, a Skagit County start-up co-founded by Maas and his brother Daryl. Their Rexville plant, about 40 miles to the south, started cranking out electricity about a year ago.
The company operates the digester and sells the electricity generated by methane produced from the manure from partner dairy farms.
The initial efficiency of the digester -- about 35 percent -- is similar to that of a coal- or nuclear-powered plant. But the heat from the methane-powered generator, which would otherwise be lost, is used to heat water that is sent to the radiant floor heating system in the greenhouse and to the digester's tank.
"And we're operating near full capacity all the time, not like a wind turbine that runs maybe 30 percent of the time," he said.
Maas said the greenhouse -- a couple of hundred yards away -- may need to supplement its heat with natural gas on cold winter days, but the heat from the digester will always be consistent.
The dairy, about 3/4-mile away, also benefits from the digester.
Manure slurry coming into the digester's tank is about 7 percent solid matter. It's mixed with food processing waste to improve the bacterial action that produces the methane. When it comes out the end of the cycle, it's about 4 to 5 percent slurry. The solids separated out become excellent bedding material for the cows, and the thinner sludge is applied to the field.
"It's less stinky than manure, which the neighbors like, and it's better fertilizer, which the farmer likes," Maas said. "It's a win-win-win process."
Funding for the $4 million plant came from several sources.
"We received a half-million dollars -- the maximum allowed -- from a USDA Rural Development grant. Also we got $1,063,724 through a stimulus-funded state energy program. We borrowed $2.4 million from Shore Bank Pacific with a USDA loan guarantee, and Farm Power Northwest added $700,000 of our own money for cash reserves and contingency funds.
"We've raised some money through middle-class investors," he said. "It gives them a chance to own a share of Farm Power, creating something everyone needs: electricity. They have a chance to own something tangible and local."
Maas said Farm Power pursued the grants "for our own risk management. As a third party, we don't know for sure the manure will always be there. We're betting on the dairy industry, but we can't just hope the cows will be there 20 years from now. It's all about the manure supply."
He said the digester will be profitable "the moment we turn it on. It creates cash. It will take 10 years to repay the loan."
The project takes about two years from initial planning to groundbreaking, Maas said.
"We start by talking to farmers, then chasing down funding," he said. "The permitting process -- air permits and building permits -- takes months. Then there's the contracts, including leasing and manure handling."
A digester in Tillamook, Ore., is now in the permitting phase. "Tillamook is very dairy-friendly, of course, so things are progressing well there," he said. "We look forward to starting other projects in Oregon."
Farm Power considered building in Idaho and California, but the Maases decided to stay close to home.
"We're based in Mount Vernon," Maas said. "We're not ready to move beyond the Pacific Northwest."