Oregon digester in operation

A manure digester located in Oregon is similar in scope and operation to a facility that Optional Energy Partners of Florida wants to build near Celina, according to those involved.

Hooley Digester, a public facility owned by the Port of Tillamook Bay, was constructed in 2003 to process manure from Tillamook County into electricity and other bio-products.

The plant cost about $4 million when $2.5 million in studies, permits and legal wrangling are accounted for, according to George DeVore, operator of the Hooley Digester.

The ultimate goal, according to Port of Tillamook Bay commissioner Jim Young, is better manure management. There are 30,000 dairy cows in Tillamook County and most dairy farmers spray liquefied manure on their fields.

The runoff can enter the valley's four rivers, which flow to the coastal bay, he said.

The conception of the facility was driven by the runoff's adverse effects on the local oyster industry, DeVore said.

"I don't think they're going to go on forever spraying stinky manure on fields," Young said, adding that he believes future mandates - including air and water quality - will limit the practice.

Although Hooley Digester is a publicly-owned plant, it is similar to a facility Andy Tangeman of Optional Energy wants to build and operate near Celina.  

According to the U.S. EPA, only 13 of the 151 anaerobic digester systems operating in the U.S. are considered regional/centralized projects such as Hooley and the proposed Celina plant, where manure is transferred from multiple farms to an off-farm digester operated by a third party.

Most digester projects in the U.S. are owned and operated by a farmer.

DeVore said the Hooley Digester- operated 24 hours a day, seven days a week by two employees - processes 60,000 gallons of manure each day from 3,000 cows at seven local dairy farms. The farmers voluntarily participate without a contract, DeVore said.

A 5,000-gallon tanker makes at least 12 trips a day to local farms to collect the manure, he said.

Methane-run generators produce 5,000 kW of electricity each day, which is sold to Tillamook. The plant also produces 60 yards of fiber, which sells for $16 a yard to nurseries, DeVore said.

The proposed plant in Celina would generate 1 megawatt of electricity and require 100,000 gallons of manure a day. Tangeman said the plant would first focus on swine manure but would not rule out the possibility of other forms.

Tangeman has said the plant would have a footprint of about 1 acre. He told the newspaper on Wednesday he wants to lease 10 acres of county-owned land on Fleetfoot Road near state Route 29. He said he has been in talks with local officials for about two years.

The plant would be a 24-7 operation with five employees and use a seven-day cycle to collect and convert the manure's methane gas into electricity, which would be sold to the City of Celina.

Participating farmers in Tillamook County pay 80 to 100 percent of the manure transportation costs, depending on the amount of solids in the waste, DeVore said. For optimal efficiency, DeVore - who samples ever load - said he likes to see 12 percent solids.

That comes out to about 1 cent per gallon per mile of transported manure.

In return for the product, the farmer receives a liquid fertilizer byproduct DeVore said doesn't smell and doubles the amount of grass grown on the land and fed to the cows.

The farmers are reimbursed their transportation fees through the state's biomass tax credit, DeVore said.

Young said the digester operation has been financially viable because of those credits, which he said eventually will expire.

"I think we would have a tough time keeping them (farmers) as clients if they weren't getting those credits," Young said.

Tangeman has stressed the Celina plant would be a private enterprise. Once proven profitable, participating farmers - who likely would pay the transportation costs - could receive a liquid fertilizer byproduct in return.