Future Ready Dairy Systems

Dairy Australia


Watts in the Dairy Shed

Objectives of Event

These events were aimed at:

  • giving farmers strategies to reduce the energy consumption of their existing dairy plant, and
  • when considering future equipment purchases, how to prioritise which of the various energy saving technologies is most suitable for their farm.

Key Messages

  • Concentrate your efforts on the areas of largest energy use. Cooling milk and heating water typically account for 60 to 70% of the energy used in the dairy shed.
  • Many plate coolers are not working as effectively as they could be. Checking the performance of your own plate cooler is simple and fixing any problems usually offers significant savings.
  • Check hot water systems; it is common to find them set at the wrong temperature, or filling or heating at the wrong time.
  • Review your plant rinse strategy – using warm water for the first rinse maximises cleaning and minimises temperature drop in the following hot cycle.
  • Attend to maintenance (insulate pipes, clean condenser fins, fix drips, etc) as the little things make a difference.

 Reflections on the Event

While the days were only attended by small numbers of farmers, those that did so were provided with excellent material by two of Victoria’s most experienced practitioners; AgVet Project’s Gabriel Hakim and DPI Victoria’s Darold Klindworth.

Darold set the scene with some general energy saving tips to ensure that you’re getting the best performance possible from your existing equipment. Darold pointed out that as the bulk of your electricity use is in cooling milk and heating water, you should concentrate your efforts in these areas. Plate coolers should be able to achieve a milk-out temperature within 2 to 3 degrees Celcius of the water supplied to it. If the gap is bigger than that, you need to investigate why starting with the following questions:

  • Is the flowrate for the water supply at 2 to 3 times the maximum milk flow?
  • Have the plates been cleaned to remove any build-up that might reduce heat exchange?
  • Is the plate cooler plumbed correctly (water supply and milk flow in opposite directions)?

Using the coolest water available to supply the plate cooler is a key factor in reducing the load on your vat’s refrigeration system.

Darold also reminded us that the heat removed from the milk by the refrigeration system can be recovered and used to pre-heat water for the hot water system. Commercial heat recovery units are available but you should have your technician investigate your specific situation before you purchase one.

Gabriel Hakim of AgVet Projects talked us through the energy assessment completed on each of the host farms. Energy assessments start with an audit of the plant’s various electrical components and matches the expected power use to the previous year’s energy bills. Typically, Gabriel’s estimated power consumption falls within 10% of the historical consumption before he starts to analyse options and recommending areas where replacing or installing new equipment is warranted.

Gabriel completed an energy assessment on Allanby Pastoral’s 720 cow dairy at Bamawm. Brendan Martin manages the dairy and was keen to have the assessment done. “We’d been concerned about the how well the cooling tower had been working but we were surprised to find a difference of almost 8 degrees between the temperature of the milk coming out of the plate cooler and the water supplied” Mr. Martin said. “Gabriel identified $6000-$7000 dollars in annual saving for not a lot of cost, which is a great outcome”. The recommendations for Brendan included work to improve the performance of the plate cooler and cooling tower as well as installation of a heat recovery system. The hot water system was also set too high for the vat – apparently a common problem and an unnecessary waste of energy.

Everyone attending the field day went home with a pair of adhesive strip thermometers and instructions to fix them on their plate coolers as a first step on the path to reducing their own energy bills. Anyone who missed the field days but is interested in getting an information pack is encouraged to call Murray Dairy on 5833 5312.

Quotes & Feedback from Attendees

“Great field day, very well worth attending”
“Good day, should have been better attended by farmers”
“Very good info packs”