Dairy Farm Energy Savings

Where do I currently consume my electricity?

The main energy uses on a dairy farm are within the milking shed - hot water heating, milk chilling, the milking system’s vacuum pump, water and effluent pumping.

How can I reduce my electricity consumption and save money?

Independent audits completed in 2010 and 2011 have shown that the average dairy farm could achieve a 16% reduction in energy with a simple payback of less than 3 years or a 28% reduction with a payback of less than 5 years.

The best opportunities to reduce your energy consumption are:

  • A Heat Recovery System can reduce your water-heating energy use by up to 56%.
  • A Vacuum Pump Variable Speed Drive can save you up to 58% on your Milking System energy use.
  • Milk Vat Insulation can help you achieve energy savings of up to 18% on your Milk Chilling.
  • Energy Efficient Lighting can reduce lighting energy use by up to 66%. Note that lighting only represents around 2% of the total farm energy use.

In some regions there are off peak tariff structures where night rates are much cheaper than day rates. Depending on the amount of equipment running during the off peak period (often from 23:00 to 07:00) using these tariff structures can offer good cost saving in comparison with anytime tariff structure.

In each section are tips on how you can save energy as well as details on some energy-saving products. It will also help you determine which options will be the best value for your farm.

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In 2010/2011 an independent energy consultancy company, Smart Power Ltd carried out energy audits of 150 farms across the country for a pilot programme commissioned by the Ministry of Agriculture and Forestry (MAF), Energy Efficiency and Conservation Authority (EECA) and Fonterra Cooperative Group to establish the potential for electricity on New Zealand dairy farms.

The following table has been created from the results of these audits. It shows Energy Use Indexes per cows and per tonne of milksolids, including or excluding irrigation.

  kWh/cow kWh/cow
(Irrigation excl)
kWh/milk solid tonne kWh/tonne m.s.
- (Irrigation excl)
Minimum 85 85 226 210
Average 211 169 595 477
Maximum 1,179 335 3,105 1,001

Note: that the size of the farms audited were ranging from 200 to 1,000 cows and that the average farm size was 420 cows with a production of 155,000 Kg milksolids (season 09/10). These averages are higher than the national average 376 cows/ 123,000 kg as smaller farms were excluded from the panel.

When irrigation is excluded the average milking operation in the panel used an average of 73,900 kWh of electricity per annum. If irrigation use is included the average farm electricity use increases to 112,100 kWh. Note that for a better comparison, irrigation should be excluded from the annual energy use calculation.

The following table shows the regional variation in electricity use with farm location.

  Farms in Sample Average Production (kg ms) Electricity use
per unit production
(kWh / '000 kg ms)
Electricity per cow
milked (kWh / cow)
South Island 41 237,200 450 180
Lower North Island 38 112,100 480 165
Waikato / Auckland 56 119,800 506 169