ONE of the largest dairy farms in the United States is making the most of its manure.
Fair Oaks Farms in Indiana has taken on the energy market in a big way - and is also recovering nutrients in the leftover water and returning them to the paddock. More recently, it grows algae in the excess water from the energy digesters as a form of protein for the cows.
Gary Corbett, the chief executive officer of Fair Oaks Farms in Indiana, spoke at the Australian Dairy Conference in Geelong, last week - telling the crowd that the business milked 37,000 cows for the liquid milk market - and handled up to 1.6 million gallons of liquid manure, which was fed into six anaerobic digesters.
"In six to 12 months, we will produce more energy than we'll consume," Mr Corbett said.
The manure is harvested from the barns three times per day.
"We look at it as if we are harvesting two different products - milk being the first and manure the second," he said.
But there was one challenging aspect at the beginning, which was dealing with the sand in the manure.
"We found sand was the best material to use in the barns as bedding, but it's proved to be an extra cost in terms of the digesters…because it clogs them up really quickly and we didn't know that," he said.
To overcome that problem, Fair Oaks Farms installed a pre-treatment for the manure, costing the business an extra $1 million.
The digesters then turn the manure into biogas, which is used to run the generators, free stall barns and milking parlours.
"We produce 100 per cent of our own electricity needs, but the challenge was we produced so much electricity that it blew away what we needed and we sold the rest to the grid," he said.
But the ability to extract a premium from the energy companies was simply not there.
"A great model is to have 50pc of the energy going to the farm and 50pc going to the grid, and the payback is pretty good," he said.
"We probably had 5pc going to the farm and 95pc to the grid.
"It was not a good investment."
So the business looked at alternative option, which generated a return.
In response, they developed a scrubber - which drove the Co2 off the hydrogen sulphate. This allowed them to produce 100pc methane - or natural gas.
But now they had the ability produce renewable natural gas, what could they use it for?
"We chose to own the largest fleet of tractor trailers in the US that run off the compressed natural gas," Mr Corbett said.
They manage 45 tractors, which run 70 loads daily.
One of the biggest advantages in the energy is that not only is it renewable, but it represents a 41pc reduction in the carbon footprint compared to diesel - and a $2/gallon cost advantage.
"It was a great switch for us," he said.
Fair Oaks Farms also started off establishing three gas stations, and then followed that up by developing a subsidiary company to expand throughout the South East region.
"We were really pioneers in this area," he said.
The digesters also have waste products at the end of the gas process, including a loam material, which can help to thicken soil.
"The second thing you get is a lot of water, but its high-nutrient water," he said.
"It's got a lot of nitrogen in it and a lot of phosphorus and potassium."
Mr Corbett said they chose to run this water through their irrigation pivots back onto the paddocks or it is injected.
But the problem with the nitrogen was that it was extremely volatile and most of it was likely to be lost to the atmosphere.
The concern with the phosphorus was it was being applied to the paddocks in equal amounts to the nitrogen, which was not required.
"The Government looks at that as a potential problem and it could cost you," he said.
"But because there was such a huge reservoir of nutrients in there, we felt there had to be better systems we could develop."
The answer was nutrient recovery.
Towers of sulphuric acid were established to run the nutrient-rich water through, therefore creating a solid form of nitrogen.
"To become self-sufficient in nitrogen is a huge thing," he said.
The second step was to source a centrifuge to bring out the phosphorus, which resulted in an efficient way of applying the nutrient.
But even after that process, there was still leftover water that carried some nutrients.
"We are now growing algae on the water as a source of protein for the cows," he said.
In addition, there's a weed called Duck Weed that grows wild in the US, which Fair Oaks Farms now grows too.
"It's got more protein in it than soybeans," he said.
"You can harvest it like cranberries, dry it, and put it through your Total Mixed Ration (TMR).
"And instead of $450/tonne soybean, you've Duck Weed meal."
In the past two years, Fair Oaks Farms has also signed an agreement with Mars to trial growing algae for human use.
"I didn't think I would live long enough to see manure management become rocket science, but I think we are right there now," he said.
"There are opportunities out there."
Tourism can tell ag's story
CAN agriculture afford not to tell its story?
Gary Corbett, who heads up one of the biggest dairy farms in the United States, says no.
Fair Oaks Farms milks 37,000 cows and decided to open up its farm gates to the public - and interact with consumers - in the late 90s.
"Farmers used to think the world stopped at their farm gate," he said.
"But now, anti-farming groups film things on-farm and agriculture is constantly finding itself on the defensive. I felt we had to break that paradigm - and I made the decision to be on the offensive."
He said he was proud of what Fair Oaks Farms did and thought the best thing was to show the consumers too.
In January 2004, the business began its tourism venture - and a decade later it boasts 550,000 visitors annually.
In addition, to its dairy business, visitors now have the opportunity to view a 3000-sow pig farm too.
