Energy & Water in the dairy

Different sources of energy are available to produce electricity for use in the dairy. Some sources are renewable (e.g. solar, wind, hydro) while others finite (e.g. coal, gas, oil).  Energy can be used to produce heat (e.g. solar hot water).

In Australian dairies, electricity is the dominant form of energy. About 40% of a farm’s electricity is used to heat water. The remainder is split between cooling milk (~30%), dairy pumps and motors (~20%) and lighting (~10%).

Using energy efficiently will benefit farm operating costs. Obtaining electricity using renewable energy sources such as solar and wind technologies will reduce the farm’s contribution to climate change through lower greenhouse gas emissions.

There are many practical and often simple ways to use energy more efficiently.

Energy is also consumed in buildings and products. Selecting products and construction materials that are durable, efficiently made and generate lower operating costs are positive ways of reducing the dairy farm’s carbon footprint.

Water is a precious resource that requires careful management - in the future we will have to be more accountable for how we use it. Different applications demand water of specific quality. Save the best available quality for the most demanding applications, such as milking machine and vat cleaning, as well as staff hand washing / shower facilities. Yard washing is an ideal application for recycled water.

Energy at work on the farm

‘Ken’ is looking to milk around 1,100 cows on a new farm north of Mt Gambier. The new 60-unit rotary dairy will be built on a greenfield site. He is keen to incorporate energy efficiency in as much of the new dairy as possible. Efficient use of water is
another of Ken’s objectives.

Ken has identified three areas where he thinks efficiency improvements will have the greatest impact. The first is in the way water is heated; the second is how his milk pre-cooling could be improved (refer to InfoSheet B4: Cooling Milk for details see details in Additional Information on page 56); and the third area is how water is used at the dairy and where savings could be made. Energy-efficient lighting and other power saving devices will be incorporated into the shed design.

Improving water heating

As there will be different staff working at the new dairy, Ken says simplicity is very important. A solar hot water system with evacuated tube collectors will be used to pre-heat the water. The pre-heated water will be stored in three highly insulated tanks from where it will be fed into the electric hot water services. The 40,000-litre vat will have a heat recovery system included. The calculated amount of hot water required each day at the new dairy will be as shown in the table.

Water at work on the farm

‘Frank’ from Victoria milks 380 cows in a 30-unit dairy. The milking equipment and the milk vat each have an automatic cleaning system. Milking takes around 2¼ hours in the morning (cups on to cups off) and about two hours in the afternoon. The current water use for each part of his system is estimated below.

Knowing his current daily water use helps Frank evaluate options. Compare the ‘total water use per day’, the ‘% new water added each day’ and the ‘% re-used and/or recycled’ - they highlight the differences.

What you need to know (Victoria only)

  1. As from April 2006, the Minimum Energy Performance Standards (MEPS) for three-phase electric motors manufactured or imported into Australia became even more stringent. These new standards apply to motors rated from 0.73-185kW, which cover nearly all three-phase motors used in dairies. When buying a new electric motor, check that it is a ‘High Efficiency’ motor that complies with MEP Standard AS/NZS 1359.5-2004.
  2. MEPS also apply to other equipment such as lighting and mains-pressure electric hot water storage heaters (e.g. often used for
    vat washing).
  3. Government rebates exist (Federal, State and Local) to assist in the purchase of solar hot water systems and photovoltaic panels.  The conditions and size of these rebates do change with time. Federal information is available at www.environment.gov.au/rebates/index.html
  4. Incandescent light globes will be phased out. The Australian Government will implement the phase-out by introducing MEPSs for lighting products. More information about MEPSs is available at www.energyrating.gov.au.
  5. Energy-efficient technologies and technologies involving renewable energy are rapidly evolving. Consequently the viability of options for dairy farms is advancing - so keep watch!
  6. In Victoria licences are required for dairy shed water use. Agricultural uses of water in Victoria, including water for washing dairy sheds, requires a licence. This means:
    • all operating dairies require a licence to take and use water;
    • the volume allocated for dairy in Section 51licences must reflect actual use; and
    • water used in the dairy shed must be metered in line with national metering standards and Government policy.
    • For further information on the current requirements for water licensing, contact your water local water corporation.

Disclaimer: The following is only a guide to the law affecting farmers in the environmental field. The general area is quite complex and affected by numerous Acts and Regulations, some of which are very detailed. In addition, changes are made on a regular basis to the legislation. The precise effect in a given situation will require expert advice and this should be sought from an appropriate professional or the relevant government agency.

Additional information

These resources can help you develop your Action Plan (Organisations, their contact details and website information were correct at time of publication. This information may change without notice).

Organisation Information Available Internet Contact
Department of Primary Industries The CowTime Project has information on how to improve milk harvesting efficiency.
There are “CowTime Quick Notes” on plate cooler effectiveness, cooling and dairy lighting.
There is also a dairy energy monitor to help assess energy use.
The Farm Water Solutions project has water use worksheets, water capture and storage
calculators and case studies about water use efficiency
www.cowtime.com.au
www.dpi.vic.gov.au > farm water
www.dairyextension.com.au > dairy shed water & farm water
Ph: (03) 5624 2222
Customer Service
Ph: 136 186
Australian Department of Climate Change General Information - Covers greenhouse issues and reports on the actions the Australian Government is taking to reduce emissions and deal with climate change www.climatechange.gov.au > Carbon Pollution Reduction Scheme > Agriculture Ph: (02) 6274 1888
Your energy supplier or the government green power scheme General Information about Green Power www.greenpower.gov.au Website has contact
details for each State and Territory.
DairySA and Dairy Australia A series of InfoSheets about energy and water-efficient design and use. www.dairyingfortomorrow.com > On-farm Action > Regional On-farm Change Projects > South Australia Ph: (03) 5622 2055