‘No silver bullet approach’ to cutting energy usage
At this year’s ‘Dairy Sustainability Day’, Teagasc’s John Upton outlined some ways in which farmers can reduce their energy usage on farm – while saving money.
Firstly, he explained how farmers can quantify their energy costs per litre of milk.
He said: “If you get your electricity bills for the year and divide that by the amount of litres you are producing, you will get your energy cost per litre of milk – which is very valuable to know.”
The average cost of electricity is “€5 per 1,000L of milk sold; but there is a very large range around this on farms – from €2.60 up to €8.70”.
“If your energy costs are on the higher end of the scale, it is going to be worth your while making some changes to reduce it as much as you can,” he said.
Through studying farms across the country, John found where the main energy usage areas are on farms.
- Milk cooling – 31%;
- Water heating – 23%;
- Milking – 20%;
- Lighting – 3%;
- Water pump – 5%;
- Other – 18%.
The first thing you can do to cut your energy costs, he said, is to “change to the cheapest energy supplier and you will cut your costs by 10% straight away”.
Reducing energy consumption
Touching on ways in which you can reduce your energy consumption, he said: “There is no silver bullet approach. We need to be paying attention to the three main areas of cooling, heating and milking.
“In terms of milk cooling, you need to look at the plate cooler in particular.
The return on investment for a plate cooler is about three years and it is the number one recommendation for reducing energy costs.
For the plate cooler to be operating as efficiently as possible “the cold water to milk ratio should be 2:1”.
“For cutting energy costs when milking, a variable speed pump will cut the cost of running your milking machine by 60%,” highlighted John.
Finally, he mentioned ways in which you can cut your energy costs when heating water.
He said: “There are a few options available to us to cut our costs here.
“If you are using a lot of water you could look at switching to oil or gas, which are cheaper than electricity.
“Alternatively, you could install a heat recovery unit; this takes waste heat from the milk-cooling process and stores it in a tank of water. The more water you use the shorter the pay back time.”