After feed, energy is one of the major costs for pig producers in Scotland. This has been exacerbated in recent months as electricity prices have increased dramatically. If you are looking for ways to mitigate these costs, you will need to think about more than just reducing costs and usage. Optimising the pigs’ environment through improved utilisation and efficiency is just as important. This article will take you through some of the key steps that you will need to take if you want to optimise your pig enterprise.
Monitor and Record Your Energy Use
A survey by Teagasc found that the average energy usage on-farm was 28kWh/pig produced with a range of 18kWh to 45kWh/pig produced. This suggests that there is scope for improvement in most pig businesses.
Recording and comparing energy use can help identify potential improvements, this is particularly useful in more power-hungry areas of the unit such as the farrowing rooms where much of the energy is used for heat production. To identify these power-hungry areas, install submeters in different sections of the unit to identify where power is used. Other energy sources should also be measured as well, for example: red diesel.
By collating this data in a simple spreadsheet, you can do a comparison of energy used relative to the number of pigs over time. This will help you identify any issues that may be slowly developing or have developed between batches. Collecting this data will also allow you to compare yourself with other farms and benchmark your efficiency against theirs.
Sub-metering also allows for benchmarking of different rooms within your own business. Seemingly identical rooms may use significantly different amounts of electricity per pig produced. By identifying differences, actions can be taken – from improving insulation on north facing rooms to replacing inefficient equipment.
Good ventilation is important in pig units, performing a balancing act between helping remove excess moisture and heat from the air within the building as well as maintaining a suitable air quality without dropping the temperature below ideal levels. The provision of the optimum environment is essential for pig performance, from feed conversion efficiency to growth rates to health – achieving this perfect balance is one way to ensure energy costs per pig or kg or pig meat are reduced.
Environmental monitoring within buildings has advanced in recent years, with improved sensors linked to software systems greatly helping the process of gathering and interpreting whether your ventilation is performing optimally.
To get the most out of your ventilation system:
1. Check whether your thermostats are accurate.
The generation of heat is an expensive process in terms of energy and even a small deviation means that electricity is being wasted. The environment itself within pig buildings can led to extra wear and tear to sensors.
2. Investigate whether internal airflows are moving as they should.
Internal building obstructions can disrupt airstreams, creating unwanted drafts and cold spots. Smoke tests used along with thermal imaging can reveal fluctuations throughout a pen or building.
3. Keep your ventilation systems in optimum working condition.
This includes keeping fans and vents clean and free from dust, dirt and obstructions. Some of the more complex systems can rely on pulleys and wires, and these can lose tension over time, which will impacting on the setting and positioning of flaps and vents. Servicing should also be undertaken by suppliers according to their recommendations.
4. Consider upgrading to newer fans.
Newer fans have a lower energy requirement than older models. In light of significantly higher energy prices, the payback period for installing more energy efficient fans will be shorter.
5. Add cones to your outlet fans.
The addition of cones to outlet fans can improve efficiency by up to 15%. With flat faced outlet fans and baffles, fan efficiency is compromised due to the air disturbance caused by swirling as fast-moving air from the fans hits the static air outside. Installing a cone channels the air smoothly away, without disturbance to the fan. Please be aware that cones can however be more susceptible to wind damage and care should be taken to make sure they remain in good condition.
6. Monitor your temperatures for large variations and ensure they are within the desired range for that class of pigs.
Temperatures should not fall below the Lower Critical Temperature (LCT) for the animals. The effect of LCT on growth rate and feed intake are shown below:
Insulate Your Buildings
Modern pig buildings require suitable insulation to both keep in the heat in the building and also exclude excessive heat during spells of hot weather. Heat retention is important as this helps mitigate the effects of colder, fresh air being pulled in by ventilation systems, reducing the need for supplementary heating to compensate.
Heat can be lost through walls and ceilings. With older buildings in particular less likely to have suitable insulation. Paying attention to heat loss is particularly important in building with higher temperature requirements e.g. early-stage weaners. Retro fitting suitable composite panels or improving current fittings will help reduce energy required to keep the building at suitable temperatures and may also help improve food conversion efficiencies with animals requiring less feed for maintenance.
If you’re looking to improve your insulation, here are three good places to start.
1. Make sure your insulation is intact
Polyurethane and other types of modern insulation materials can be prone to damage by pests and vermin. Run regular checks and replace or repair where necessary
2. Check your plumbing
Heat can be lost from tanks or pipework carrying hot water throughout the unit – check these are adequately insulated.
3. Keep your insulation dry
Moisture acts as a conductor of heat therefore insulation must be kept dry where possible.
Creating Energy Efficient Farrowing Houses
Generating heat takes a lot of energy and this area of a unit can represent a large proportion of the electricity spend on a pig unit. Piglet creep areas will vary from unit to unit as well as age of building. This may range from enclosed, boxed areas to open heated areas to the front or side of the sow with heat delivered by top-down methods such as lamps or heaters to bottom-up heat pads. Farrowing rooms must also supply a suitable environment for both piglets and sows, despite both have widely differing temperature requirements.
Thermostats allow temperatures of creeps to be maintained relative to the wider room air temperature, saving energy. Automated controls can also be used gradually reduce creep temperatures as the litter grows, further reducing energy requirements.
Heat lamps or radiant heaters can also be replaced with more energy efficient heat pads. Despite having much higher capital costs, heat pads are longer lasting, much cheaper to run and can be easily controlled. You could also consider using heated water from renewable sources.
You can further reduce energy costs by enclosing creeps, retaining the heat within the creep area and reducing heat losses to the wider pen. This also has the benefits of helping to manage the different temperature requirement of the sow and her litter.
Make use of Min-Max thermometers to monitor room temperatures. These will save you energy in two ways, as when rooms become too warm this is not only a waste of energy from the generation of surplus heat but also the extra ventilation required to keep temperatures within desired ranges.
Creating Energy Efficient Feeding & Cleaning Systems
There are various feeding systems employed in pig unit with varying energy requirements; from simple bunker feeders filled by loader to feed lines carrying wet or dry feed. Feed is also mixed on farm from wet feeding mixing tanks to feed mills. To ensure your feeding and cleaning systems are energy efficient, consider the following:
1. Use Variable Speed Drive (VSD) motors where possible
These can regulate the power needed to match the motor speed required for the task in hand. This ideal for liquid feed systems and slurry systems.
2. Pre-soak or use sprinkler in rooms prior to washing
This significantly reduces the time required, and subsequently reduces the power requirement.
3. Look at washing systems
Can temperatures be turned down in power washers or is there scope to use water from slurry heat recovery?
This is a substantial topic, and further information on energy efficiency in on-farm feed mills can be found here.
More Efficient Lighting
Lighting technology has moved on greatly in the last decade with the development and widespread availability of LED lighting, which offer considerable energy savings over existing technologies such as halogen or fluorescent lights.
Other measures to improve efficiency include:
1. Changing walls and roofs to a more reflective colour such as white can greatly increase lighting levels within a space and reduce requirements from artificial means. Keeping lights clean and free of dust may also mean that fewer light fittings are required.
2. Are the lights in the right place? Fitting lighting units to existing building furniture may be convenient but does it get the best output?
3. Replacing existing lights with LED lighting reduces energy requirement significantly (typically 80-85%). LED lights are also much longer lasting. Further guidance on using LED lighting in pig buildings can be found here.
Integrate Renewables Into Your Business
Many producers have existing renewable sources of energy in place. With electricity steeply rising in price, the economics of installing renewable systems without the benefits of tariffs is becoming more attractive. There is a capital cost which will vary from farm to farm although there are several options that pig farmers can consider including established methods such as solar or heat pumps to more uncommon systems such as using warmth from slurry to heat water for use in the farrowing sheds. You can find more information on slurry cooling here.
As users of lots of energy pig producers are particularly exposed to the vagaries of the markets- taking time to review operations and buildings could trim usage and even improve animal performance, help improve energy efficiency for the unit. Any improvements should of course, be costed out beforehand, particularly where gains may be fairly small relative to costs – e.g. upgrading insulation with advice sought from suitable experts where necessary.
If you have further questions, please contact the FAS helpline for advice and support:
Call: 0300 323 0161
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