The Doolan family’s farm at Brucknell in south-west Victoria has changed a lot over three generations, but the rapid transformation of the past three years has been unprecedented.
The farm has installed a solar PV system, load shifting milk cooling, underground water tank and plate cooler, a CO2 heat pump, variable speed drives, and a power supply monitoring and feedback system. It is also trialling multi-species crops and composting.
The results have been stunning, with substantial soil and environmental improvements and long-term financial benefits, making the business a template for sustainable dairy farming.
Sam and Belinda Doolan and Sam’s brother Peter and his wife Bonnie share farm with the brothers’ parents Sam senior and Carol. They detailed their successes at a Farming Sustainably for Future Generations field day hosted by WestVic Dairy and supported by Heytesbury District Landcare Network (HDLN) and DemoDAIRY Foundation.
While sustainability has always been high on the Doolans’ agenda, the recent transformation started when the farm was chosen for a HDLN Keeping Carbon on the Farm trial in 2018, a program that has now expanded to 30 farms across Western Victoria.
The farm has been trialling multispecies cropping with different species and different tillage methods, and different rates and types of composting.
There is already a lift in the organic carbon percentage in the soil.
“We were pretty good anyway — about five to six per cent — but it’s now regularly seven, eight and even nine per cent,” Sam (Jr) said.
The improvement has not only been in the trial paddocks, it’s spreading across the farm as effluent and compost is spread further.
Visual soil assessments show there is more biological activity and worms in every plot.
The revolution of the dairy is already leading to financial savings.
In just two years, the Doolan farm’s CO2 emissions have been cut from 242.5 to 180, a 26 per cent saving from all energy audit upgrades.
The new C02 heat pump is a stand-alone system replacing an old hot water system. It meets two key demands – 85 degrees for the plant and 60 degrees for the vat.
The plant changes have led to management changes. Previously they did a plant and vat hot wash in the morning in a rushed half hour before the tanker arrived at 8am.
“We called the processor and they now pick up our milk at night so we do the plant wash in the morning and the vat wash at night, and it’s got time to heat up using the solar,” Sam said.
The tank is able to be cleaned and the pump is a natural refrigerant.
A new vacuum pump VSD has more than halved emissions and energy costs, running only when it’s needed.
The Doolans are installing a scheduling system so it can be run using solar during the day.
The new milk chiller, underground tank and plate cooler inside the dairy are all linked as part of the same milk cooling system, although they involved different tradespeople, with locals always given first preference.
Sam said the previous cooling system was outdated.
“Milk would go through the first plate cooler and get cooled by water from the old lakeside cooling tower,” he said. “After that initial cooling, it would get anywhere from 14 to 18 degrees, then it would go straight to the vat and the old cooling system would have to get it down to four degrees and it was quite energy-hungry.
“That was our only cooling system and the fans were 25 years old.
“Now, instead of using the cooling tower, the chiller steps in and we have another plate cooler right beside it, which the cold water carries through. It’s getting from 14-18 down to around 4 before it even hits the vat; all the vat is doing now is holding it at that temperature.”
The chiller runs during the day through solar power and the system accesses cold water stored underground.
The energy intensity footprint will be less than half. With the solar connection, payback period will be 6.2 years — or 9.8 years without solar.
The underground tank has about 300mm of gravel over the top, allowing people to walk on it, but you can’t drive a truck on it.
The new technologies have addressed the farm’s biggest concerns.
“When we did our original energy audit with the HDLN Keeping Carbon on the Farm project, we identified that chilling milk and heating water accounts for 50 to 60 per cent of energy in the dairy,” Sam said.
“They’re the two big ticket items to tackle first.”
The farm already had 36kW of solar power but during the past three years added another 54 for a total of 90kW.
“People will say `what about cloudy winter days?’ — but we factor that into our plans and the economics still work out and we can cover all bases,” Sam said.
“We can see through our monitoring system how much the solar is making, how much the dairy is using and what we’ve got in reserve.”
They have been able to make adjustments to better use the solar.
“We know when we can crush the grain or start the effluent pump because we have power in reserve,” Sam said.
“Between milkings, the chiller is running, the heat pump is running, the grain is getting crushed, the effluent pump is running during the day and it’s all for free because it’s paid by solar.”
The dairy has also changed from halogen globes to LED lighting and new skylights have been installed.
Payback time will vary depending on the new technology and its cost but the longest is just nine years and the average six to seven years.
The project has been supported by dollar-for-dollar funding from the Victorian Government.
The Doolans say they are trying to keep in front of the game by introducing sustainable farming practices.
“Like New Zealand, I think there will be tariffs and limits on fertiliser usage and I wouldn’t be surprised if governments introduced criteria that farms have to adhere to for greenhouse gas emissions,” Sam said.
“We’ve got to set it up for our children like Dad did when we were growing up. We want to encourage the next generation and have things in place that they can carry on.”