Energy Efficiency & Farm Equipment
Research has concluded that on-farm energy end-uses providing farmers with the largest savings potential include: motors, lighting (with irrigation being the largest motor application), and onsite transportation (including fuel use decisions).[i] While particular efficiency measures might be more useful to some farms because of their unique characteristics, such as the needs of a farm-type or region, much of the following research is generally applicable to all farms, no matter their location or farm-type. Also remember that the farm’s residence, or “home building envelope,” contributes to energy expenses, and should be included in any energy efficiency evaluation. Larger farms are certain to implement these techniques, which make it critical that smaller farms also consider them in order to remain competitive and sustainable. In addition, with more consumers focused on buying locally grown products that have been farmed with “green” practices, smaller farms have the benefit of marketing their crops and products as being produced with these energy efficient techniques. Again, the sections below outline the measures that provide farms with the most potential for savings, or that give you “the most bang for your buck.”
As noted above, motors are one of the largest energy users on the farm. In fact, motor end-uses account for 18 percent of known and categorized energy uses on the farm at a national level.[ii] Accordingly, they also present one of the greatest opportunities for cost savings on the farm. It is estimated that the adoption of a combination of general and application-specific measures on the farm will produce a savings of approximately 30 percent.[iii] According to ACEEE researchers, the highest potential savings can come from pumps, fans, blowers and compressors.[iv] Specifically, efficiency measures in the motors of pump applications are anticipated to produce a thirty-four percent savings.[v] Motor measures used to improve the energy efficiency of your farm will come from either a change in process on your farm, change in technology, or through motor replacement. Below you will find tips and suggestions about what to consider when implementing motor efficiency techniques on your farm. Further, financial benefits from implementing these changes will also be discussed.
Irrigation presents a large energy- and money-saving potential in the agriculture sector. Possible irrigation energy savings are estimated at 436 million dollars nationally, and represent twenty-nine percent of the total potential motor savings.[vi] Motor energy use is the primary use of energy for all farm-types that use irrigation because of the energy it takes to pump water to and through the system.[vii] It is important to note that the benefits of increasing energy efficiency in irrigation are not solely (or even primarily) energy related.[viii] Much of the benefit stems from the water-savings that result from improving irrigation efficiency.[ix]
Irrigation Energy-Saving Tips
There are several common sense guidelines a farmer can follow to improve irrigation efficiency on the farm. First, it is important to keep irrigation engines and motors serviced and well-tuned.[x] Second, make sure electric motors, switches, and control panels are clean and free of dirt, insects, or bird nests. These factors add to an inefficient motor.[xi] Third, check connections to ensure they are tight, and lubricate moving parts that require it.[xii] For example, to avoid sprinkler system inefficiency, inspect the system regularly, and make minor repairs such as stopping leaks, replacing worn nozzles, and trimming the impeller, as necessary.[xiii] Fourth, to prevent over-watering consider using an irrigation scheduling method that times irrigation watering for more efficient fuel and water use. Such methods include starting irrigation before soils are completely dry and using larger amounts of water on fewer acres per irrigation to move water through fields quicker and more efficiently.[xiv] Also, address watering methods to avoid patchy water distribution and inadequate pressure.[xv] Either of these problems will make it impossible to maintain correct soil moisture levels, leading to crop stress, reduced yields, waste water, runoff, soil erosion, and many other problems.[xvi] Implementing all, or even one, of these techniques is guaranteed to combat these irrigation inefficiencies and save you money through lower energy bills!
Addressing equipment and management efficiency together is critical to creating the most energy efficient irrigation system on the farm. In addition to these common sense tips, there are more specific measures a farmer can take to address equipment inefficiencies and irrigation management inefficiencies. For instance, there are publications that describe recommended irrigation system installations, explain how utilities charge their irrigation customers for electricity and describe common causes of wasted energy, as well as common energy-saving hardware improvements. Also, there are do-it-yourself methods to estimate the efficiency of electrically powered irrigation systems.[xvii] In addition, see your irrigation dealer or an extention agent to find information on the following:
What is the net water application rate for my irrigation system,
How do I calculate the number of hours the system should be operated,
What are different methods to measure flowing water in an open channel or pipeline, and
What are possible suggestions for irrigating with limited water supplies.[xviii]
Finally, all farms should be encouraged to find publications explaining how to maintain irrigation pumps, motors, and engines for peak efficiency, including descriptions and diagrams of recommended installations, checklists for maintenance tasks, and a troubleshooting guide.[xix]
Dairy farm-types are another candidate for motor energy efficiency programs due to their large use of pumps on the farm.[xx] In
For most dairy farms, the best way to improve energy efficiency is through the refrigeration system’s design, operation and maintenance. However, the farmer should address refrigeration system efficiency measures in a logical, step-by-step manner.[xxii] If a farmer is planning a major expansion or renovation of his dairy farm refrigeration system, it may make sense to install multiple energy saving measures. These measures, in order of priority, include:[xxiii]
1. Refrigeration Heat Recovery (RHR) Units
2. Scroll Compressors
4. Variable Speed Milk Pumps
These measures can reduce refrigeration related energy costs substantially and maintain, or even improve, milk quality. They reduce refrigeration requirements and/or capture waste heat and use this excess heat energy to pre-heat water. However, before installing one or more of these measures, you might want to consult with farm refrigeration experts, because you may inadvertently increase your energy usage. For example, installing an RHR unit and a precooler may cause an increase in energy consumption if all factors are not considered when designing the new system. Experts can also help you avoid damage to equipment or equipment failures. This factor is of greatest concern for farms with 120 cows or fewer, but all farms can benefit from expert advice before proceeding.[xxiv] Even if a major refrigeration overhaul is not expected, there are still some specific measures the farmer can take to improve the efficiency of the system that are addressed below.
Diary Farming: Use Variable Speed Vacuum Pumps for Milking
The vacuum pump used for milking not only must operate for long hours during the day, but it tends to use a lot of energy. Standard pumps with single speed drives operate at a constant speed of seven to ten cubic feet per minute (CFM), per milking unit. On the other hand, by installing a variable speed drive on the pumping system, the pump speed can be lowered to two CFM per milking unit, yet additional power remains available if needed. The variable speed drive unit alters the vacuum power so that no more energy is needed than necessary, and the controllers on the pump are sensitive enough to prevent injury and milk back flow. The variable speed units, with corresponding controllers can lower the energy costs of a dairy vacuum system by half.[xxv]
Dairy Farming: Use a Water Cooled Plate Cooler
Plate coolers, also known as plate heat exchangers, use well or spring water to lower the temperature of milk as it flows from the milking system to the collection tank. Using a plate cooler can speed the cooling process so that the milk is at a lower temperature, reducing the milk temperature by an extra thirty to forty degrees. This means that the compressor does not have to expend as much energy as it would other wise.
The use of machinery and on-site transportation dominates energy end-use on the farm. Whether tilling the fields with the tractor, moving crops with a fork-lift, or through utilization of the combine or hay baler, the average farmer spends twelve percent of their total identified energy budget fueling machines and on-farm vehicles to perform these tasks.[xxvi] Important to note, however, is that this statistic is formulated knowing that there is an enormous amount of unavailable information with regard to national energy use in agriculture. The actual expenditures are likely to be much higher, which means the resulting savings will also increase.
Since the tractor is one of the most utilized and essential tools of farms across
Because of the high use of machinery and on-site transportation on the farm, it is no surprise that fuel energy use is one of the most important ways to improve the energy efficiency of your farm. Researchers have found that gasoline and diesel are by far the fuels most used in the sector, making up seventy-five percent of agriculture fuel use all together.[xxxii] Diesel use dominates because of the high use of diesel fuel in product transport.[xxxiii] Fuel expense savings is of primary importance to any farmer, especially to smaller farmers who need to do more with less. Fuel consumption varies widely due to variations in tractor efficiency, soil moisture conditions, crop yields, and other factors.[xxxiv] Here are ten ways a farmer can increase fuel efficiency of the farm:[xxxv]
- Reduce the number of trips associated with spring seedbed preparation. With today’s modern planter units, crop residue does not create the problems it used to with seed placement and depth control. For most field situations, one tillage trip over the field in the spring should provide adequate leveling of the soil and seedbed preparation.
- Change to a no-till planting system where field conditions permit. This is especially true for soybeans, as no-till soybeans are an easy and proven way to maximize yields without doing any tillage.
- Reduce the depth of tillage associated with seedbed preparation if you are using a mulch-till or reduced-till system. In most cases, spring seedbed preparation should be performed no deeper than three to four inches. This will reduce the power and fuel requirements needed.
- Combine trips across the field may also reduce fuel usage. Producers using 28 percent UAN solutions may be able to mix their pre-plant or pre-emergence herbicides with their fertilizer and apply with one trip over the field. Be sure to check with your ag-supplier regarding chemical compatibility of the herbicides and fertilizer products before mixing these together.
- Custom apply either or both herbicides and fertilizer this spring. Although an application charge will be charged by the commercial company, they may be able to do it more cost and fuel-efficiently than an individual producer.
- Use post-emergence herbicides for annual grass and broad-leaf weed control. By applying the post-emergence herbicides after the crops and the weeds emerge, producers know the crop’s seedling plant population and the infestation of weed species present. In some cases, producers may only need to do “spot” treatments of either the broadleaf or grass herbicide in the field. Also, by waiting until after the crop and weeds emerge for treatment, weed control is usually improved.
- Avoid unnecessary use of the cultivator for weed control unless weed populations cannot be controlled with herbicides.
- Match field equipment to the appropriate sized tractor. If excess tractor horsepower is used for the job, fuel efficiency declines dramatically. Conversely, if a small horse-powered tractor is used and the tractor becomes overloaded for the job, fuel efficiency also suffers. In many situations, research studies show that a large front-wheel assist tractor or four-wheel drive tractor may actually provide the best fuel efficiency if it is appropriately sized to a large field cultivator or other tillage implement. A good rule of thumb is to usually select the smallest and lightest tractor for the job that needs to be done to enhance fuel efficiency and reduce soil compaction.
- Perform general tractor maintenance before going into the fields this spring. Take time to properly clean air and fuel systems including replacement of filters. Also be sure to properly lubricate tractors and equipment as this will result in enhanced fuel efficiency and equipment operation when you get to the fields this spring.
- Examine use of the pick-up truck and trips to town. According to research studies, for many farms, one of the largest users of fuel involves the pick-up truck. Without a doubt, the pick-up truck is an essential component of the entire farming operation. However, where possible, combine trips for equipment, seed, chemicals, and to arrange for other agri-business services. Also, using the telephone or the home computer may reduce a number of unnecessary trips to town.
Below is an outline of some additional practical ideas on what to do to save on fuel and increase farm efficiency:
Upgrading Diesel Engines or Converting from Gasoline or Electric
One smart way to improve the fuel efficiency of the vehicles or machinery on your farm is to replace any gasoline engines used on the farm with a diesel engine. Even better would be replacing old diesel engines with newer ones that contain more advanced technology. The figure below shows that only fifteen percent of the gasoline you put into the tank is used to move the vehicle or equipment. The rest of the energy is lost to engine and driveline inefficiencies or idling. Therefore, the potential to improve fuel efficiency with advanced technologies is enormous.[xxxvi]
Diesel engines are more powerful and fuel-efficient than similar-sized gasoline engines (about 30-35% more fuel efficient). Plus, today’s diesel vehicles are much improved over diesels of the past.[xxxvii] Today’s diesel engines must meet the same emissions standards as gasoline vehicles. Advances in engine technologies, ultra-low sulfur diesel fuel, and improved exhaust treatment have made this possible. Further improvements are made by combining an upgraded engine that advances in emission control technologies with “clean” diesel fuels, such as ultra-low sulfur diesel[xxxviii] and biodiesel created on your farm. Using this technology reduces hazardous air pollutants.[xxxix] Energy efficient engine and transmission technologies are continuously improving.
The purchase price (initial cost) of an electric motor has been estimated to be only 1% to 2% of the total operating cost over the lifetime of the motor.[xl] Because the purchase price is so insignificant, the farmer’s first step in investigating energy savings by purchasing a new electric motor, or upgrading a current electric motor should be to determine how much it costs (energy) to operate current motors on their farm.
Gear up and Throttle Down
Running your tractor at the proper RPM is essential to fuel efficiency. In all cases consult the guidelines issued with the tractor. You should make sure that you don’t overload the engine. However, if you are hauling hay bales or pulling a rake, consider reducing the engine RPM by “gearing up and throttling down.”
Tires should always be inflated to the proper pressure. Over-inflated tires decrease traction, create ruts in soft soil and can deteriorate sidewall tread. Also, be careful to not overload your tires. Overloading can cause pre-mature tire wear, increased soil compaction and increased fuel consumption resulting from increased rolling resistance. A
Make sure to perform general maintenance on your farm equipment, especially before and after harvest season. Properly lubricated tractors and equipment will result in better fuel efficiency.[xlii] Also, be sure to change the filters in the air and fuel systems. Finally, use appropriate equipment ballast to keep wheels from slipping and using more fuel.[xliii] Ensuring that you follow the proper maintenance schedule will not only increase fuel efficiency, but will extend the life of the tractor.
Minimizing the use of heavy-duty pick up trucks when driving into town can surprisingly save hundreds of dollars a year on gas. Larger trucks and pick ups are important to farm operations, but they should be saved for those tasks that require their power and hauling capacity. Also, remember to use air-conditioning selectively and considering combining trips to town so that one trip can accomplish multiple tasks.
[i] Elizabeth Brown and R. Neal Elliott, ii On-Farm Energy Use Characterizations (2005) (note: throughout the reports, the researchers express the extreme conservative nature of the potential savings because of the relatively limited data indicating how energy on the farm is used and further lack of data on savings potentials for particular energy end-uses — where there was no data indicating savings, they assumed that there were no savings available in that end-use.) available at: http://www.aceee.org. Insightful data by farm-types that are considered to be a relatively comprehensive representation of all farms across the country (poultry, dairy, greenhouse/nursery, cattle feedlots, oilseed and grain farming, fruit and tree, and hog and pig farms) is also available at www.aceee.org.
[ii] Elizabeth Brown and R. Neal Elliott, 6, Table 2, On-Farm Energy Use Characterizations, American Council for an Energy Efficient Economy (2005).
[iii] Elizabeth Brown and R. Neal Elliott, 5 Potential Energy Efficiency Savings In The Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[iv] Elizabeth Brown and R. Neal Elliott, 4 On-Farm Energy Use Characterizations (2005).
[v] Elizabeth Brown and R. Neal Elliott, 4, Table 2, Potential Energy Efficiency Savings In The Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[vi] Elizabeth Brown and R. Neal Elliott, 16, Table 12, Potential Energy Efficiency Savings In The Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[vii] Elizabeth Brown and R. Neal Elliott, 14 On-Farm Energy Use Characterizations, American Council for an Energy Efficient Economy (2005).
[viii] Elizabeth Brown and R. Neal Elliott, 15 Potential Energy Efficiency Savings In The Agriculture Sector, American Council for an Energy Efficient Economy (2005).
[ix] See, Elizabeth Brown and R. Neal Elliott, 15 Potential Energy Efficiency Savings In The Agriculture Sector, American Council for an Energy Efficient Economy (2005). Citing (CEC 2003).
[xx] Elizabeth Brown and R. Neal Elliott, 15 On-Farm Energy Use Characterizations (2005).
[xxi] See, Elizabeth Brown and R. Neal Elliott, 15 Potential Energy Efficiency Savings In The Agriculture Sector, American Council for an Energy Efficient Economy (2005).
[xxv] Wisconsin Public Service Corporation, Handout, available at: http://www.wisconsinpublicservice.com/farm/vacuum.asp.
[xxvi] See, Elizabeth Brown and R. Neal Elliott, 6 On-Farm Energy Use Characterizations, Table 3, American Council for an Energy-Efficient Economy (2005).
[xxvii] See, Elizabeth Brown and R. Neal Elliott, 4 Potential Energy Efficiency Savings In The Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[xxviii] Elizabeth Brown and R. Neal Elliott, 17 Potential Energy Efficiency Savings in the Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[xxix] Elizabeth Brown and R. Neal Elliott, 6 Potential Energy Efficiency Savings In The Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[xxx] Elizabeth Brown and R. Neal Elliott, 17 Potential Energy Efficiency Savings in the Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[xxxi] Elizabeth Brown and R. Neal Elliott, 6 Potential Energy Efficiency Savings in the Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[xxxii] Elizabeth Brown and R. Neal Elliott, 5 On-Farm Energy Use Characterizations American Council for an Energy-Efficient Economy (2005).
[xxxiii] See, Elizabeth Brown and R. Neal Elliott, Potential Energy Efficiency Savings in the Agriculture Sector, American Council for an Energy-Efficient Economy (2005).
[xxxv] These ten tips were provided by The University of Illinois Extension, available at: http://web.extension.uiuc.edu/macon/rr/i80_33.html.
[xxxviii] Ultra-low sulfur diesel (ULSD) will begin replacing conventional diesel fuel starting in 2006. The new fuel will contain 97% less sulfur than conventional diesel—sulfur will be reduced from 500 parts per million (ppm) to 15 ppm. See, http://www.fueleconomy.gov/feg/lowsulfurdiesel.shtml, or http://www.epa.gov/nonroad-diesel/ for more information.
[xli] California Farm Bureau Federation, Fuel Efficiency on the Farm, available at: http://www.cfbf.com/issues/energy/flex.cfm. See also, Kleber P. Lancas, Shrini K. Upadhyaya, Muluneh Sime and Sayedahmad Shafii, “Overinflated Tractor Tires Waste Fuel, Reduce Productivity,” California Agriculture 51(2), 1996.