Energy bills can be reduced by up to 30% with minimal outlay.1 Here are some tips to reduce your energy bill.
Know your energy use
Identify the major areas of energy demand around the farm. Check the condition and operation of equipment and monitor power consumption over a period of time, for example one week.
How does your electricity use compare to the average use figures in the table below?
Average cost of electricity per
unit of production
0.49c /litre of milk
Identify where energy is used, assess and take action
Compile an energy checklist for your farm by walking around your buildings at different times of the day and seeing where energy is used. Check on building insulation, lighting, heating systems, pumps, ventilation, water heating and milk cooling.
Insulate Farm Buildings Adequately
Upgrading loft insulation in the family home from 100mm to 300mm will save €250 a year on a typical bill of €1600.4.
Farm buildings including the farm house vary greatly in age, use and construction materials. The construction (in terms of air- tightness) and insulation of these will determine the overall energy consumption. Upgrading the insulation in your home and in heated buildings such as pig and poultry units will reduce your energy costs.
Upgrade insulation on electric hot water tank will save €130/year 5
Correct Lighting – Can Reduce your Cost by 50%
Lighting is one of the easiest areas where savings can be made. Lighting costs can be reduced by up to 50% (6) by providing the right amount of light, in the right place at the right time with effective lighting equipment.
Light efficiency is measured in lumens per watt. The higher the lumens per watt the greater the lighting efficiency.
Replace the 500 watt halogen flood light with an equivalent light output 150 watt High Pressure Sodium lamp.
It will save €128 /year and it lasts 10 times longer!7
For yard lighting, High Pressure Sodium lights are best. They offer a balance between colour rendering and high efficiency.
They should be controlled with a dawn to dusk sensor and time switch .
Think about safety and pay attention to the suitability of fittings for the humid, dusty and warm environments often found in livestock and poultry buildings.
The new energy efficient standard is the T5 fluorescent tube with dimmable electronic ballast, mounted in weather-proof housing (plastic).
Replace older T12 fluorescent tubes with T5 tubes using a new fitting or a conversion kit for your existing fitting and save €17/year/tube8.
Heating and hot water – fixing a small leak of 1 litre/hour can save you up to €760/year9
A regularly serviced farmhouse boiler can save as much as €160 on a typical annual heating costs of €1600 (SEAI)
A modern new household boiler e.g., a condenser boiler can reduce energy bills by 25% and save €400/year (SEAI).
In the farmhouse: set your thermostat as low as is comfortable, check your timers, bleed radiators and service the boiler annually. If the temperature setting is out by just 1°C, it can mean an increase in energy consumption of 15% (10).
On a dairy farm to save money on water heating ensure that all pipes and tanks are well insulated, minimise the distance that hot water has to travel and use night rate electricity. Make sure that timers are set for the right time and are keeping time.
Correctly sized Plate Heat Exchangers can reduce the energy costs for cooling milk by up to 50%, which can give a saving of €9/cow/ year.
Milk needs to be cooled from 37°C down to about 4°C. Milk cooling costs are typically 40% of overall costs of milking. Pre-cooling is achieved by passing the hot milk through a Plate Heat Exchanger (PHE) before entry to the bulk tank. Cold water is pumped through the opposite side of the PHE. The cold water absorbs a portion of the heat, thus pre-cooling the milk and contributing to hot water supply.
Use of water to pre-cool the milk before it enters the tank will save about 30% of milk cooling costs – an energy saving of €5/cow/ year 12.
Install a variable speed drive to the vacuum pump in the milking parlour. It can give you a 60% reduction in pump running costs, equivalent to €4/cow/year.
Consider installing a variable speed drive (VSD) to a vacuum pump. It can result in savings of over 60% on vacuum pump running costs per year (13).
Energy savings can be made on ventilation systems through better controls, more efficient air movement and less reliance on
mechanical systems. The careful choice of fans, the design of ducts, regular maintenance and cleaning reduce the energy costs and improve efficiency
23% of energy use in pig farms is for ventilation A 40% improvement in energy efficiency can be achieved through more effective control and routine maintenance of the ventilation system. This has resulted in savings of €4/finished pig/year in an integrated unit.
ADAS. Managing Energy and Carbon – the farmer’s guide to energy audits. ADAS, UK.
Figures for Dairy, Pig and Poultry sourced in Teagasc 2011, Energy Use in Agriculture. Teagasc Oakpark, County Carlow.
Figures from Sustainable Energy Authority of Ireland (SEAI) based on a four bedroomed detached house see here.
Based on reinsulating a 200 litres water tank heating water from 14°C to 80°C on night rate electricity (10c/kWh) where insulation has deteriorated.
Sustainable Energy Authority of Ireland – Exterior Spaces Lighting Guide.
Changing from a 500watt halogen flood light to an equivalent light output 150 watt high pressure sodium lamp; savings= 350wattx10hrs/dayx365days = €127.75 based on manufacturer’s data.
Replacing a 6ft T12 tube at 95Watts with 6ft T5 tube at 53 Watts = 42Wattsx2000 for hours x 20cents/1000=saving of €16.80 per tube, based on manufacturer’s data.
A leak of 1 litre/hour results in a hot water loss of 8,500 litres/year equivalent to 3800kWh/year. Cost: 3800kWh x 20cents/kWh day rate = €760
ADAS. Managing Energy and Carbon – the farmer’s guide to energy audits. ADAS.UK.
Teagasc. 2011. Energy Use in Agriculture. Teagasc, Oak Park, County Carlow. Savings on plate heat exchangers – Overall dairy energy consumption average is 350kWh/hd/year and cooling costs for milk are typically 40% = 140kWh, (with 70% on night rate of 10c/kWh and 30% on day rate at 20c/ kWh). 140kWh for milk cooling per head = 140×70%x0.1+140×30%x0.2) =
€18.20×50% = saving €9/cow/year.
Farm Energy Centre, UK.
Carbon Trust. 2005. ECG089 Energy Consumption Guide – Energy Use in Pig Farming. Carbon Trust, UK.