Improving the energy efficiency of existing farm buildings, equipment and processes could give a quicker and longer-lasting financial return than any other investment activity including a renewables project.
In farming energy costs may only represent a small percentage of turnover. But reducing them can directly increase profits and competitiveness. At a national level we need to improve our energy security by reducing our dependence on imported fossil fuels.
Energy efficiency is the first step you take to reduce your energy bills. You carry out an energy audit on your unit to identify any savings that can be made by doing things differently. Once these savings have been made then the renewable energy options can be considered.
With farmers typically paying 15c–16c/kWh for electricity, displacing as much as possible either through energy efficiency or renewable generation, makes financial sense. The displacement value will improve as the cost of energy increases. The historic increase in energy costs has been higher than the Consumer Price Index (CPI).
High energy prices are not going to go away. Dairy farms for example have a heavy reliance on electricity, mostly for collecting and cooling milk, heating water and lighting-provides many energy-conservation opportunities. A cut in energy costs ultimately results in the same bottom line benefit as an increase in sales.
Opportunities for savings
Lighting, heating (including grain drying and water heating), ventilation, air circulation and cooling/refrigeration are the largest energy usage on farms. There are a number of measures which could be adopted in order to help save on energy use, including:
- Energy Control Systems: make sure that all energy control systems are set properly to ensure that energy is only being consumed when required. This includes all timers and thermostats. Systems such as compensatory control or optimum start controllers can help stabilise temperatures and they are programmed to regulate heat output depending on weather conditions;
- Lighting: there are a range of lighting options available from fluorescent tubes, compact fluorescents, high pressure sodium, metal halide and light emitting diodes (LED). These vary in length of life and electricity usage. LEDs, fluorescent strips or sodium lamps should be fitted for best efficiency. Daylight sensors and occupancy sensors should also be considered;
- Insulation: pipework and buildings should be insulated, hot water tanks lagged. This would be most necessary in farm buildings where temperatures would be critical such as pig farrowing units or poultry units;
- Servicing: make sure to service boilers regularly otherwise they reduce in efficiency. Fuel savings of 10% per year can be achieved with regular boiler servicing. Pipework, compressors and motors require regular servicing;
- PVC Curtains: the installation of PVC curtains or automatic self-closing doors can reduce heat losses in cold stores;
- Monitor: the best way of knowing where your losing money on energy is to monitor your electricity bills and observe what machines and systems which are the largest energy consumers on your farm. You can then monitor the effectiveness of the energy savings deployed;
- Energy Efficient Technology: pre-cooling of milk in-line by well or mains water before it enters the tank has a number of advantages. A variable Speed Drive (VSD) on the vacuum pump is able to adjust the rate of air removal from the milking system by changing the speed of the vacuum pump to equal the rate of air admitted to the system. A VSD can give savings of over €400 per annum. Pre-cooling through plate meters can halve the cooling costs. Under floor heating pads in farrowing units instead of using infrared bulbs and the use of variable speed fans for ventilation will improve efficiency.
Recording energy usage
The majority of farmers have a good idea of how much they spend annually on both heat and electricity but very few, record accurately and monitor their on-farm energy consumption on a regular basis. The pressure of daily farm business and more often than not gets overlooked.
Smart meters
A smart meter works by communicating directly with your energy supplier, so the company will always have an accurate meter reading and there is no need for you to take a meter reading yourself. Smart meters can work in a variety of different ways, including using wireless mobile phone type technology to send data.
An expected national rollout of smart meters will improve energy recording and farms will most likely make significant savings by using such tools. A smart meter is like a speedometer in a car it allow you to see how much electricity you are using right now.
The potential savings will be most significant in the more energy-intensive businesses such as pigs, poultry, horticulture, dairy units and farms which are heavily reliant on electricity for cooling or refrigeration.
Taking action
Before you embark on an all-out energy efficiency campaign you need to determine where energy is used on your farm and within the various activities of your farm business. This will generally be achieved through an energy audit.
The Sustainable Energy Authority of Ireland (SEAI) are partners with Teagasc on the Get Farm Financially Fit campaign. The SEAI has funded many on-farm energy audits and generally deal with larger groups of farmers to make comparisons such as discussion groups. For further details on Better Energy Work Places contact the SEAI on 071-915 97 30. Energy audits will quickly identify where energy is being consumed and where the savings can be made.
The larger energy consumers who would typically pay over €15,000 per year are in a better position to justify the cost of a full professional on-farm energy audit. For lower energy users the audit would not go into as much detail. Energy audits will not only identify energy efficiency measures but can also identify situations where renewable technologies such as wind turbines, heat pumps, biomass boilers etc. can make sense.
Conclusion
The more information you get the easier it is to develop a strategy to give netter on farm energy savings. Energy audits are particularly relevant where expensive renewable energy projects are planned.
Case study: Laragan pig farm, Elphin, Co Roscommon
Heat pump technology
Heat pumps use similar technology to fridges to extract heat from the air, ground or water to provide space and water heating. Heat pumps require electricity to run and the CO
2 and financial cost of this electricity needs to be taken into account. A heat pump’s coefficient of performance (CoP) is the measure of how many units of heat you get out for each unit of electricity you put in.
Laragan pig farm in Elphin, Co Roscommon, is owned and managed by Dick Togher and Ned O’Connor. In 2011 the cost of FLO-gas at the pig farm was €24,744 to provide heating for 35 sow farrowing places and approximately 1,800 First stage weaner places. The farm has more farrowing places but these are heated with electric heat pads.
The management decided to keep the FLO-gas system intact and use it as a back-up to the heat exchange system. Between December 2012 and June 2015 the usage of FLO-gas has cost €2,270 or €908 (Including VAT) each year.
The annual electricity usage is measured as there is a smart meter on the system. The heat pumps run on electricity. Heat pumps provide a low temperature heat output and are therefore best suited to meeting a low heat demand, for example, well-insulated properties with underfloor heating. The current electricity usage is 24,711 kWh (kilowatt hours) per year and if this is costed at 15.89 cent per kWH (Including VAT) it costs €3,927 including VAT.
The cost of the heat pumps was €28,000 and re-plumbing to the central station cost €14,000 giving a total installation cost of €42,000. The annual saving in fuel cost is €24,744 less (€908 plus €3927) = €24,744 -€4,835 =€19,909.
The simple pay-back is €42,000 / €19,909 = 2.1 years. There were no grants or subsidies received by Laragan Farms to help deliver this project. Heat pumps are a form of low grade heat which may be relevant to some farm businesses. It is imperative to know your overall costs before you take any action and calculate the payback.
Ger McCutcheon Teagasc
Author main piece: Barry Caslin, Teagasc