HOMER CITY--When Ludwig van Beethoven wrote his Fifth Symphony in 1806, the Brookside Dairy already was in production near here.
Owned and operated by the William George family, the farm now produces more than just cow's milk. Finding a new use for one of the byproducts of that process, the family recently started tapping its ready supply of manure to generate electricity.
Last Friday, the public was invited to the dairy to take a look at the process that converts fresh manure into energy.
State Rep. Dave Reed, who grew up not far from Brookside Dairy, recounted how he used to pick up milk there in the mornings for his family.
"It's exciting to see a project like this come to completion," Reed said.
Along with Reed, several other state and local officials were on hand for a press conference and tour of the facility, including Sen. Don White and the Indiana County Commissioners, as well as Indiana County Conservation District Manager Jim Resh and Pennsylvania Department of Agriculture Secretary Dennis Wolff.
"This is truly what a family farm looks like," Wolff said of the Brookside operation.
"We really feel that agriculture is at the edge of the new frontier," he noted.
Farmers have always been a hefty producer of food and fiber, but soon, he added, they will be the providers of food, fiber and energy.
The cost of the manure-to-electricity conversion project at Brookside was significant, but the effort received state support through an Energy Harvest Grant.
The chief project component, a manure digester that extracts gas from the animal waste, cost $434,000. A power line upgrade needed to utilize the energy produced with the gas cost an additional $70,000.
The digester admittedly is a small-scale project, but its implications for Indiana County will be great, according to those involved.
Brookside Dairy stretches across 1,200 acres of farmland, and its 400 cattle produce about 10,000 gallons of manure in a day.
Through the intricate digestion process, the manure generates 80 to 85 kilowatts of energy output, resulting in about 65,000 kilowatts of energy production yearly. That's enough energy to supply 55 homes with power.
Resh explained, as the demand for power increases during steamy summer weather, electric companies "have to beg off of another pool of power," which can add considerably to utility costs.
But, "Now, we have a facility right here" to provide extra back-up power, Resh noted.
The farther electricity has to travel through lines, the more power is lost, especially in the winter months, Resh added. Now that a small pool of electricity is available at Brookside, it could be used more efficiently, powering homes that are located nearby.
Construction of the digester system at Brookside involved many contractors, including Keller Engineers, Inc., Groffdale Concrete Walls, Inc., Terry Stiles Excavating, Mashan Communications and Electric, Tom Smith Heating and Cooling, Martin Machinery L.L.C., Bork Welding and Maple Mountain Construction Co.
Aaron George represents the eighth generation of his family to work at Brookside. He recently graduated from Penn State University, with a degree in agricultural systems engineering.
He is one of the family members charged with day-to-day operation of the manure digester.
George spends the first 15 minutes of every day checking on the digester's engine/generator.
"The generator is pretty much maintenance-free except for oil changes. It's pretty much automated," he said.
Twenty-eight 54-inch fans are always in motion in the Brookside Dairy barns, creating 6-1/2 mile-per-hour winds to keep the cattle cool and at peak milk production.
"The effects of hot weather on cattle are significant," Wolff said.
"The fans are a big draw from the electricity, but the heat will lower dairy production," George explained.
Scrapers were installed in both the farm's free stall/milk cow barn and a dry cow/milking parlor to collect manure for the digester process.
In order to create peak levels of production and methane gas recovery, manure should be as fresh as possible when it's introduced into the digester.
Once the cows in either barn relieve themselves of waste, the scrapers move into action, running on a timer and operating 24 hours a day.
The scrapers drop the manure into tanks, where it is mixed to the proper consistency, about eight to 10 percent solids.
Four times a day, 2,500 gallons of mixed manure is pumped up into the digester by means of a diverting valve.
"The digester is very finicky," George said. "It's like a living organism. Once it gets used to a certain food, you don't want to change it too drastically."
Two types of bacteria grow in the manure digester and aid in the digestion process: acidic bacteria and methane bacteria. Both begin to grow when the manure reaches 97 degrees.
The acidic bacteria feeds the methane bacteria and creates a combustible "biogas" when it reaches 60 to 65 percent methane levels.
"The bacteria is very sensitive," George said. "It's takes up to two months to create the bacteria, but it will take as little as a day to destroy them."
In order to create high levels of methane gas, the manure must be stored in an oxygen-free environment in warmer temperatures.
This is done by circulating the manure underneath a large circular dome (58 feet in diameter and 14 feet deep) that is sealed with a polyethylene cover.
Methane bacteria will begin to digest the carbohydrates and cellulose in the manure in a 25- to 35-day process.
The manure is warmed up by heat from the digester's engine, which transfers to a heat exchanger on the center wall.
The dome's flexible cover allows oxygen to escape while trapping the valuable biogas created by the methane bacteria.
A series of PVC pipes under the dome cover collects this biogas, which is pressurized and used to power a boiler and the digester's engine/generator.
Any unused gas is returned to the digester chamber to further aid in the digesting process.
Digester temperatures are maintained through the boiler only when the engine/generator is undergoing maintenance.
The resulting digested manure is roughly 64 percent methane gas, with carbon dioxide making up the difference along with traces of hydrogen, sulfide and other gases.
To create electricity from the captured methane gas, a caterpillar 3306 engine is used, capable of generating up to 90 kw of power from biogas with a 60 percent methane content.
Besides the energy advantages, the manure digester also has biological benefits. Once raw manure is sent through the digester, its pH is increased to around eight, which is better for the soil once the manure is applied.
One of the biggest biological benefits, though, is the reduction of odors.
"There's a big difference," George said.
"It's awful when it first comes out.
"With the digester, the ammonia is removed."
The result is "not a pungent smell, it's an earthy smell, similar to mushroom manure."
After it has created peak bacteria levels, the digested manure is fed from the dome into a holding tank. Then it's used to cover the farm's fields.
"The manure is now a chemical compound instead of a nitrogen compound, and can be used right away by plants," Resh explained.
Also, any weeds seeds that are in the manure are destroyed in the digestion process, which reduces the need for herbicides once the manure is applied to the fields.
Officials noted the impact an operation such as the one at Brookside Dairy could have for farming in Pennsylvania.
Indiana County Commissioner Bernie Smith pointed out that Brookside Dairy is where he got his milk growing up just over the hill in Homer City.
The manure digester, he said, makes for a more affordable and more efficient form of energy, "And it keeps the farmers here in Pennsylvania."
Wolff said, ideally, this type of renewable energy in the United States could negate the nation's dependence on the Persian Gulf for oil.
"We should all work to conserve," Resh added.
Even with 400 animals producing manure for the system, the Brookside digester still isn't running at its maximum capacity.
According to George, the digester was designed to handle the waste of up to 750 head of cattle.
