Oregon State University Energy Efficiency Center

Agricultural Energy Assessment

Walkthrough Checklist

Mikhail Jones

8/9/2011

The purpose of this guide is to introduce the user, both technical and non-technical, to common opportunities that may be found in an agricultural facility to reduce the energy consumption.

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Table of ContentsPreface............................................................................................................................................................1

Disclaimer......................................................................................................................................................1

Non-Specific Opportunities...........................................................................................................................2

Lighting......................................................................................................................................................2

Building Envelope.....................................................................................................................................3

Motors........................................................................................................................................................5

Air Compressor..........................................................................................................................................6

Refrigeration..............................................................................................................................................6

Boilers........................................................................................................................................................6

Renewable Energy.....................................................................................................................................7

Crop Production Specific...............................................................................................................................9

Irrigation....................................................................................................................................................9

Tractor and Field Operations...................................................................................................................12

Greenhouses.............................................................................................................................................15

Grain/Nut Dyers.......................................................................................................................................18

Dust Collection........................................................................................................................................18

Animal Production Specific.........................................................................................................................19

Animal Housing Ventilation....................................................................................................................19

Milking Operations..................................................................................................................................19

PrefaceIn recent years the agricultural sector has seen significant growth in energy service needs. Agricultural operations can use various technologies and resources to help reduce their energy consumption and environmental impact while improving their financial situation. The purpose of this guide is to introduce the user, both technical and non-technical, to common opportunities that may arise in an agricultural facility to reduce energy consumption. It is beyond the realm of this guide to support the user in completing a full energy analysis. It is meant to serve as a reference to help users identify potential opportunities to focus on and improve. This guide is definitely an introduction, so the coverage is rather broad, but the information is compatible with a professional understanding of the subject.

This guide aims to increase energy awareness by providing managers with a self-assessment method of improving operations and reducing costs. The reader is supplied with the information necessary to evaluate specific cost saving projects common to most operations. These projects are drawn from my personnel experience conducting rural energy assessments, thus this may have resulted in an emphasis on some parts better know to me, at the expense of other equally important parts.

Material herein is organized by industry sector to aide in identifying applicable opportunities. Furthermore content is subdivided based on energy and technology systems. Each section outlines a brief overview of the common opportunities in a particular energy system including various situations in which the opportunity may be applicable.

DisclaimerThe contents of this report are offered as guidance. The author does not make any warranty or representation, expressed or implied, with respect to the accuracy, completeness, or usefulness of the information contained in this report. The author does not assume any liabilities with respect to the use of, or for damages resulting from the use of, any information, apparatus, method or process disclosed in this report.

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Non-Specific OpportunitiesThe following section outlines potential energy saving opportunities common among most agricultural facilities. Depending on the facility some of these opportunities may not be applicable. Industry specific opportunities are covered later in this guide.

Lighting

Turn Off LightsThe quickest and most obvious way to reduce lighting energy consumption is to turn off lights when they are not needed. Often lights are turned on at facility start up and left on regardless of traffic until facility shut down. This is especially true in low use areas such as storage rooms and warehouses. While this approach is advantages due to its low implementation cost, it usually requires an extensive publicity program before it becomes effective.

Listed below are some situations where turning off lights should be considered.

Lights are commonly left on in low use areas such as warehouse, storage rooms, or break rooms. Lights are left on during lunch or work breaks.

Efficient Lighting RetrofitGreat advances in lighting technology have occurred in recent times which have lead to increased efficiencies and longer lamp life. Most of these lamps have been designed as direct replacements of older models to reduce upgrade costs; however some do require ballast or fixture replacement as well. Fluorescent and LED lighting fixtures are much more efficient than Halogen, Incandescent, and Mercury fixtures. Facilities with old lighting systems should consider retrofit options to reduce energy consumption and improve light quality.

Listed below are some recommended lighting types and what purposes they best serve.

Compact Fluorescent - These should be used in place of incandescent lights. They are extremely efficient and last over 10 times as long as standard incandescent lights.

T-8 Fluorescent - These should be used for general task lighting. These are much more efficient than incandescent lights and the standard T-12 fluorescent lights and have the advantage of a quick re-strike time allowing them to be used with a motion sensor system.

T-5 Fluorescent - These should be used in high bay applications such as warehouses in place of metal halide, halogen, and mercury lamps. They are extremely efficient and have the advantage of a quick re-strike time allowing them to be used with a motion sensor system.

Motion Sensor ControlMany low use areas such as warehouses, storage rooms, and shops can benefit from installing motion sensors. Motion sensors can turn off lights when the area is not in use reducing lighting fixture operation hours thus reducing electricity costs, associated labor and maintenance costs. Because motion sensors

will turn lights on as needed, lighting fixtures will have to have fast re-strike times meaning only fluorescent fixtures will be compatible.

List below are some situations where motion sensors should be considered.

Lights are left on in low traffic areas with fluorescent lights. Lights are connected on a single breaker yet only a portion of the lights are needed at a given

time.

Photocell Sensor ControlPhotocell sensors can dim or turn off lights when sufficient day lighting in the area is reached, in some cases this can reduce lighting fixture operation hours thus reducing electricity costs, associated labor and maintenance costs.  They can be used for outside lighting or for inside building lighting next to windows, doors, or sky lights.  Typically they are only useful inside a building if lights are located within 15 feet of an outside lighting source.

List below are some situations where photocell sensors should be considered.

Lights located next to open windows, large doors, or skylights when natural light is sufficient. Night safety or security lighting is left on during the day.

Building EnvelopeBuildings are the structure and backbone for any modern facility, they provide a means of seperating the inside from the outside world.

InsulationHaving a properly insulated building can reduce heating and cooling loads thus reducing energy and or natural gas costs. Insulation is measured in R-values, the higher the value, the better the insulator is and the more resistant it is to heat loss. Places to check for proper insulation are your attic, ceilings, walls, basement walls, floors, and crawl spaces.

Listed below are some useful tips on how to increase insulation efficiency.

Install attic vents along the entire ceiling cavity to improve ventilation. This will help with moisture control and reduce cooling bills during the summer.

Use lighting fixtures designed for direct insulation contact to reduce heat loss through and around fixtures.

Make sure to take into account all building and climate factors before replacing or installing insulation.

Use higher density insulation on exterior walls and ceilings.

Efficient WindowsMany on farm building have windows to provide natural lighting, ventilation, and a view to the outside world, unfortunately, a considerable amount of your energy bill can be lost out windows as well. During cold winter months your heater must work harder to account for heat lost out windows. As much as 25 percent of your heating bill can be lost out windows. During hot summer days your air conditioner must

work harder to cool air heated by solar energy passing through windows. If your buildings utilize single pane windows or you are building a new building, consider upgrading to more efficient double or triple pane gas filled low-e windows. They will reduce heating costs and eventually pay for themselves.

Listed below are some useful tips on how to increase window efficiency without replacing with new ones.

During Wintero Cover windows from the inside with a heavy duty clear plastic to reduce infiltration.

Plastic must be sealed around window to work properly.o Close curtains during night and open them during the day.o Keep windows clean especially on south side of buildings to let in solar heat.o Install interior or exterior storm windows.

During Summero Install white window shades, drapes, or blinds especially on south side of building to

reflect solar energy.o Keep curtains closed during the day especially on south side of buildingo Apply a reflective film on south facing windows to reduce solar gain.o Install awnings on south and west facing windows.

Heating and CoolingHeating and cooling account for more energy usage than any other system in a typical building. No matter what kind of heating, ventilation, or cooling system you have in your building, significant energy savings and increased comfort can be realized by properly maintaining and or upgrading your system. Even then, a properly maintained system can waste a considerable amount of energy through in proper insulation, air sealing, and thermostat setting. Therefore is important to not only make sure your system is efficient but also make sure all connected systems are efficient as well. A building is only as efficient as its weakest link.

Listed below are some useful tips on how to increase heating and cooling efficiency.

Set your thermostat as cold as you are comfortable with during the winter and as warm as you are comfortable with during the summer. This reduces the system heating/cooling load drastically reducing energy costs.

Make sure that all vents are clear of obstructions as this reduces effectiveness while increasing fire hazards.

Clean ventilation filters on a regular basis to reduce fan load.

Seal Air LeaksMany older buildings have over the years developed cracks and air leaks. This is a sure way to lose heat and increase your heating/cooling bills. By sealing cracks, seams, and leaks you can easily and cheaply decrease your buildings heat loses thus reducing associated energy costs.

Listed below are some useful tips on how to seal air leaks.

The first thing to do is check the entire building for potential leaks. This can be done by feel or you can use a lit incense stick on a windy day to check for any disturbances from the interior. If a

leak is found the smoke will blow horizontally instead of vertically. Check windows, doors, vents, and any visible cracks or seams.

Use weather stripping on any doors or windows that leak. Check for dirty spots on walls, ceiling, and floors, this could be an indicator that a air leak is

present. When the fireplace is not in use make sure to close off the flue stack, otherwise hot air will vent

out continuously

High Speed DoorsFacilities with frequently use drive in coolers may benefit from use of high speed doors controlled by remote or motion sensors. If frequent trips are going to be made in and out of a cooler the doors are often left open. This increases the load on the cooling system thus increasing energy consumption. By using automatic high speed doors, the amount of time cooler doors are left open can be reduced, increasing efficiency.

Listed below are some situations where high speed doors should be considered.

Cooler doors are typically left open to allow ease of access during certain times of use. Cooler doors have to be manually opened or closed.

MotorsMotors are a crucial part of any mechanized process and provide a means to do the majority of the mechanical work in most facilities.

Optimize MotorsIt is common for motors to be progressively upsized in a facility as they are replaced. This can lead to motors that are significantly oversized for their current application. While motors will only consume as much energy as the load placed on them, efficiency does decrease at part-loads. Motors that operate below 50 percent of full load may suffer from severing reduce efficiency warranting replacement.

Notched V-BeltA notched belt reduces slippage and allows the belt to bend around pulleys with less effort. Loss in motor speed and efficiency occurs when a standard V-belt slips within the groove of the pulley. The friction between the standard V-belt and pulley generates heat within the belt, resulting in an energy loss and a shortening of belt life. Notched V-belts can improve efficiency by approximately 2% to 4% over standard V-belts.

Air Compressors

Reduce Set PressureCompressing air is expensive, with as much as 90% of compressor power dissipated as waste heat. Because compressed air is clean and readily available, it is often taken for granted and set pressures are often ignored. Running a high set pressure on the compressor and then regulating it down for facility use

is very inefficient. It is much more efficient to reduce the compressor set pressure. For every 2 psi reduction in set pressure a 1% decrease in associated energy costs is feasible.

Reduce Air LeaksCompressing air is expensive, with as much as 90% of compressor power dissipated as waste heat. Because of this it is important to keep leaks to minimum. Because compressed air is clean and readily available, it is often taken for granted, and leaks are often ignored. Most facilities have a leak load of around 30%, it is unrealistic to eliminate all leaks but a 10% leak load is a reasonable objective. By reducing leaks the compressor demand is reduced thus decreasing associated energy costs.

Listed below are some tips on how to detect leaks.

Most leaks can easily be detected by ear or feel and are located at pipe connections. An ultrasonic leak detector can assist in locating quiet leaks in noisy environments.

Refrigeration

Refrigeration TuneRefrigerant condensing temperature is determined by compressor discharge pressure, which is generally controlled by the condenser fan capacity. Compressors require less power and energy to operate against a lower discharge pressure. However, to reduce this discharge pressure, the condenser fans must operate more often. Since condenser fans use significantly less energy than the compressor, reducing compressor use leads to significant energy savings.

BoilersThese systems present large opportunities for energy savings due to the high costs of fossil fuels. This is compounded by the need to supply combustion air. In most systems, the 79% of the atmosphere that is not oxygen must be exhausted hotter than it is taken in along with any unburned oxygen.

Boiler Combustion TuneWhen a boiler burns fuel, there is a certain amount of excess air that is required to ensure complete combustion, but any amount beyond this limit is not useful in the combustion process and is released into the stack and out to the atmosphere. This excess air is being heated, but is not being used by the boiler, reducing boiler efficiency.

Boiler Fan Variable Speed Drive (VSD)Boilers commonly use an outlet damper on the forced draft fan to control the flow of air entering and exiting the boiler. Partially closed dampers are inefficient because significant power is required to overcome the added flow resistance. Variable Speed Drives work by varying fan impeller speed instead of restricting airflow. When a small amount of air is required, the VSD slows the motor down to produce the required airflow while using the smallest amount of energy possible. Likewise, it will increase motor speed as more air is demanded by the boiler.

Insulate PipesUn-insulated lines allow greater heat loss. This heat must be made up by the boiler, reducing the boiler’s capacity to provide steam to necessary points in the system. Insulating the steam pipes will reduce heat loss, saving energy, and increasing the system efficiency.

Renewable EnergyAlternative energy usage is energy generated from natural resources, it is clean, naturally replenished, and will play a key role in generating a reliable energy future. There are a number of renewable energy opportunities that may be available on your facilities operation such as solar, wind, biomass, and the generation of bio fuels.

Solar Thermal ArrayThe amount of solar energy that strikes the earth every day is enormous. Solar thermal heating is a proven technology that harnesses solar radiation from the sun to heat water in place of conventional methods. Typical systems use an insulated, weather proof box containing a dark absorber plate under one or more layers of transparent or translucent covers, while more complex systems utilize vacuum tubes or concentrating panels. A heat transfer fluid is pumped through a closed loop system, which passes through the absorber plate, to absorb heat. A heat exchanger then transfers the heat from the fluid to water in storage tanks. This hot water can then be used to supplement heating needs. This will significantly reduce hot water heater fuel consumption and associated costs while also reducing CO2 emissions.

Photovoltaic ArrayThe amount of solar energy that strikes the earth every day is enormous. Photovoltaic's use a special material that silently and directly converts this energy into electricity at the atomic level without using complex machinery usually associated with electrical generation. This is possible because of a material property known as the photoelectric effect, which allows the material to absorb photons of light and release electrons. These free electrons can then be captured resulting in an electrical current that can be used as electricity. Because the resulting electrical current is Direct Current (DC), an inverter must be used to convert it into Alternating Current (AC) before it can be used.

Anaerobic DigesterUsing methane to generate electricity can help reduce or eliminate current electricity costs. In some cases enough electricity can be generated to sell back to the utility company. Anaerobic digesters use bacteria and heat in an oxygen free environment to convert volatile manure into usable methane gas. The biogas is then piped off and can be burned in an open flame or sent to an engine/generator to produce electricity.

Listed below are some key benefits to using waste to generate electricity.

Odor Control - The anaerobic microorganisms break down potential odor causing compounds. This offers a reduction in odors by up to 97 percent almost eliminating odors completely.

Clean Fertilizer - Because the digestion process is anaerobic it kills almost all unwanted weeds and pathogens. The digestion process also reduces the volume of manure solids by up to 90 percent leaving a high quality concentrated fertilizer.

Environmental - Most farms store manure in pits or lagoons where methane gas is generated and released to atmosphere. Methane gas is 21 times more potent than carbon dioxide in causing global warming. By capturing and burning the methane gas farmers could help reduce the rate of global warming.

Reduce Water Contamination - The improved manure handling system used by anaerobic digesters reduces potential surface ground water contamination.

Listed below are some situations where an anaerobic digester should be considered.

Large streams of waste are produced year round such as manure or plant material.

Wind TurbineWind turbines take energy from the wind, and convert it into useful electricity. They can last over 30 years, require minimal maintenance, and produce zero carbon emissions once they have been installed. Installing a wind turbine will provide an alternative source for the facility's energy and reduce CO2 emissions associated with electrical generation of electricity used. They come in variety of sizes and styles ranging from 1 to 125 meter diameter blades. Following are some key distinctions between types and sizes as well as points on which are best suited for different applications.

Listed below are some useful facts to help you determine which type of wind turbine will best suite your facility.

Towerso Guyed - The least expensive type of tower, usually consisting of a lattice pipe structure

with supporting guy wires. The disadvantage is that they require a guy wire radius of 1/2 to 3/4 the height of the tower requiring extra area to accommodate them.

o Self-Supporting - More expensive than guyed towers but require less room to install. They can either be a solid tubular structure or a lattice pipe structure.

o Height - Wind speed increases with height while turbulence decreases thus a taller tower will produce more power than a shorter one.

Systemo Stand-Alone - Not connected to the utility grid. Require deep-cycle batteries to store

excess energy not used and save it for when the wind is calm.o Grid-Connected - No batteries are needed although a power conditioner (Inverter) is

needed to make the power compatible with the grid. Turbine - Wind turbines require a average wind speed of at least 10 - 15 mph to be economically

feasible. Check your available wind resources and average wind speed at the National Wind Technology Center web site.

Crop Production SpecificIndustries in the crop production subsector grow crops mainly for food and fiber. The subsector comprises establishments, such as farms, orchards, groves, greenhouses, and nurseries, primarily engaged in growing crops, plants, vines, or trees and their seeds. (NAICS 2007)

IrrigationIrrigation accounts for a substantial portion of typical crop production operations electrical costs. Therefore it is important to find ways to conserve water and reduce associated operating costs.

Variable Speed Drive (VSD) ControlMost irrigation pumps run at full speed no matter the requirements set forth by the system. This is very inefficient particularly when a wide range of flows rates and pressures are needed throughout the season. A more energy efficient system uses a variable speed drive (VSD) to slow the motor speed to match the end use requirements. A VSD will also allow pumps to "soft start", by slowly ramping up the motor instead of trying to do so instantaneously. This will ensure the peak demand is never more than the motors full load operating amps, reducing associated demand costs. This will also reduce motor wear and damage caused by hard starting as well as maintenance costs associated with water surge/hammer and sprinkler head damage.

Listed below are some situations when VSD controlled irrigation should be considered.

Pumping systems implementing bypass or throttling control valves to regulate flow or pressure. Pumping systems that draw from a well or river with a depth that varies significantly throughout

the season. Center pivot or lateral move systems that have an end gun that turns on and off at varying

locations in the field. Center pivot or lateral move systems that have a corner span or drop span that turns on and off at

varying locations in the field. Center pivot or lateral move systems located on terrain that has significant elevation changes. Pumps that service multiple separate systems that may not all be on at once (ex. A pivot, traveling

big gun, or hand lines that operate at different capacities and times).

In summary, a Variable Speed Drive should be considered in any irrigation system that operates under varying flow and pressure requirements.

Low Pressure IrrigationMost irrigation systems utilize a high pressure impact sprinkler system to deliver water to the field. These systems typically operate from 60 - 120 psi. This is a very inefficient method for delivering water to a field. A more energy efficient system uses low pressure drop down nozzles that require less pressure to operate at the same flow rate as conventional sprinklers. These low pressure systems can operate at pressures as low as 15 - 20 psi without a reduction in flow rate. This reduces pump demand requirements, by installing either a variable speed drive (VSD) or a new properly sized pump/motor combination, the pump is then able to match the new pressure requirements reducing energy consumption.

Listed below are some situations where a low pressure retrofit should be considered.

Center pivot or lateral move systems utilizing impact sprinklers can easily be retrofitted with low pressure drop down nozzles.

Depending on crop type and field shape, a high pressure system can sometimes be replaced with a low pressure center pivot or lateral move system. This will also reduce labor requirements associated with irrigation.

Drip IrrigationMost irrigation systems utilize a high pressure impact sprinkler system to deliver water to the field. These systems typically operate from 60 - 120 psi. This is a very inefficient method for delivering water to a field. A more energy efficient system uses drip irrigation lines that require less pressure to operate at the same flow rate as conventional sprinklers. Drip irrigation systems drastically reduce energy costs when compared to conventional methods by reducing the operating pressure that the pump must work against. They also have higher application efficiencies which result in less overall water pumped by reducing evaporation, run-off and irrigation of unnecessary area. Drip irrigation systems can operate anywhere between 70% to nearly 100% application efficiency.

Listed below are some situations where drip irrigation should be considered.

Center pivot or lateral move systems utilizing impact sprinklers can easily be retrofitted with dragging drip hoses.

Overhead impact sprinklers are utilized as the primary method of irrigation in orchards or vineyards.

Optimize Pump SizeAll pumps are designed to operate at one Best Efficiency Point (BEP) on its capacity versus head performance curve. When system requirements move away from this point the efficiency of the pump deteriorates. If system conditions have changed since the initial selection of the pump, they may be operating away from the BEP, therefore wasting energy. An oversized pump often works continuously against a throttle or damper causing even greater inefficiencies. Sometimes system requirements can easily be modified to allow pump operation at its BEP. Otherwise the pump should be replaced with one that matches the system requirements.

Listed below are some situations where pump replacement should be considered.

Change in requirements that make once properly sized pumps and motors oversized. The system requirements cannot be modified to match the pump BEP.

Replace/Repair PumpPump efficiency deteriorates during its expected service life. These additional losses are commonly due to impeller wear, bearing fatigue, and damaged seals therefore wasting energy. Pump efficiency can also deteriorate at accelerated rates due to other environmental causes including; operating outside of the designed net positive suction head requirement causing cavitation, pumping fluids that contain abrasives such as dirt or sand, and pumping fluids with acidity levels above pump design specifications. Pumps should be tested every two to three years to confirm that they are performing properly and that no significant losses are occurring. Pumps can feasibly reach efficiencies as high as 80 percent, however they can also operate at abysmal efficiencies with no real apparent signs.

Listed below are some situations where pump repair/replacement should be considered.

Efficiencies Above 60% - No action is necessary although efficiency may be improved by adjusting impeller clearances.

Efficiencies Between 50% and 60% - Adjusting the impeller to housing clearance is recommend as efficiency may increase by 10-15%

Efficiencies Between 50% and 55% - Damage to the impeller is likely and repair is recommended as efficiency may increase by 20%

Efficiencies Below 50% - Replacement is recommended in most cases.

Optimize Distribution SystemIrrigation distribution systems are often expanded upon over time to match a growing facility. This often leads to distribution systems that are inappropriately sized for their current use. Typically a system is expanded upon and a large pump is installed to meet the requirement. This leads to larger flow rates than the distribution system was initially designed for increasing line pressure losses due to friction. Replacing mainlines with larger ones can reduce these losses and allow the pump to operate more effectively. There are a number of other ways to optimize irrigation distribution system efficiency as well. Most of them offer very minor improvements in efficiency and thus are typically not cost effective. These optimization practices should always be considered when installing or retrofitting a system.

Listed below are some situations where a optimizing the distribution system should be considered.

A higher capacity pump was installed to meet system requirements increasing flow. Additional lines have been added onto the system to expand to another area or system. Main line gaskets are leaking causing excess pump load. Worn irrigation nozzles, nozzle typically have a service life of 7 to 10 years after which water

uniformity and flow can become affected.

Irrigation SchedulingOver irrigation wastes water, energy and labor while also increasing soil erosion, washing away valuable nutrients thus reducing crop yields. These nutrients then have to be replaced in the form of fertilizer increasing fertilizer costs. Under irrigation stresses the plant and soil and also causes a reduction in yield. As a general rule of thumb, irrigation should begin when soil water content drops below 70 percent. By using moisture sensing devices, flow rate meters, and tracking the amount of water applied these problems can be avoided increasing yield while keeping water and electricity usage to minimum. On average a farm using irrigation scheduling will consume 15 to 35 percent less water than a farm not using it, decreasing pump run times and loads.

Listed below are some situations where irrigation scheduling should be considered.

Soil moisture content is not measured to base irrigation schedule on. A large variety of soil moisture techniques can be used to monitor soil moisture levels ranging from hand feel and appearance to gravimetric soil moisture sampling.

Fields are irrigated on a fixed schedule not according to plant and soil requirements. Irrigation should be based on soil type and root depth, avoiding application of more water than can be contained in the root zone which will lead to leeching.

Fields are irrigated during the day time and not at night. Watering fields in the morning when temperatures and winds are minimal can reduce water loss.

Irrigation is based one top soil appearance. Do not worry about the dryness in the top inch of soil, dig down 4 to 6 inches to test soil moisture in the root zone as this is most critical.

In summary, irrigation scheduling should always be considered but is often times not quantifiable without a good usage profile. Often times farmers have a good idea of how much water needs to be applied from past experience and are cautious to change established practices. While a best practice this is typically not recommended.

Tractor and Field OperationsFuel is a major cost on modern farms, especially with the continually rising fuel prices. Therefore it is important to find ways to conserve fuel and reduce associated operating costs.

Tractor OperationTractors play an important role in most modern farms, and are used for a wide variety operations and procedures. Operators can obtain a number of speeds by adjusting the transmission gear ratio while maintaining the same engine RPM. Within each gear ratio there is further adjustment available with the governor setting lever (or the idler lever if the tractor doesn't have a governor). In most cases tractor field speeds are determined by the implement and not by the tractor power available. Most operators run tractors at full throttle using the transmission gear ratio to vary speed. Significant increases in fuel efficiency are expected if the governor speed is reduced and a faster gear ratio is selected. This is particularly true in cases where the tractor and equipment are not properly matched and the tractor is operating at less than full load.

Listed below are some tips on how to optimize tractor operation.

The engine speed should be reduced as far as possible while staying in its designed power range. Check the operator’s manual to find the engines power range. Generally, it is safe to reduce engine speed by a maximum of 30 percent without getting out of the power range. Operating a tractor outside side of its designed power range will only decrease fuel efficiency and increase fuel consumption.

It is important to not overload or lug the tractor. Lugging the tractor causes the engine to generate more torque at low engine speeds then it was designed for. This can result in engine overheating and in some extreme cases, engine failure. Key indicators to overloading are excessive black smoke, or the tractor is sluggish in response when throttled up to full throttle. The tractor should accelerate quickly when throttled up, if it doesn't, the engine RPMs should be increased until the engine becomes responsive to quick throttle change.

Only reduce throttle during non PTO operations unless the tractor is equipped with a variable speed PTO that can keep its speed with reduced engine RPMs.

Reduce TillageThe simplest method to reducing tractor fuel consumption is to reduce the number of field operations on each field. Tillage operations are done to prepare a seedbed, apply fertilizers, and to cultivate for weed control. Excessive tillage is common on farms and causes increased fuel consumption, operating labor costs, and equipment wear. Excessive tillage can also be counterproductive by increasing soil compaction, reducing organic live and releasing carbon into the atmosphere. In some cases an operation can be eliminated or replaced with a less energy intensive operation while yielding similar end results. Combining operations by connecting implements can also reduce fuel consumption by allowing a more

appropriately sized tractor to perform the task. Furthermore, no-till can drastically reduce fuel consumption while providing nearly identical yields as tillage operations. Benefits of no-till include reduced soil compaction and more organic growth in the root zone layers.

Listed below are some situations where reduced tillage should be considered.

Multiple passes of each operation are performed at varying angles. While sometimes necessary, fields are typical over tilled.

Facility does not utilize no-till planters and corresponding no-till practices.

Precision AgricultureTypically tractors and other equipment are manually steered by operators. Operators tend to overlap more than necessary, which increases operation costs and reduces efficiency. GPS automated steering reduces the overlap necessary to ensure full implement coverage. Using GPS and either assisted or automated steering technology in agriculture can offer a wide range of benefits, including reducing crop input and application costs, as well as increasing safety, productivity, and efficiency.

Listed below are some key advantages to precision agriculture practices.

Reduce Skips and Overlaps - Automated steering systems can virtually eliminate application overlap and skips, reducing wasted time, seed, fertilizer, and fuel.

Reduce Soil Compaction - Setting up auto guidance coordination between applications can reduce soil compaction by using the same wheel tracks every time, increasing yields.

Reduce Operator Fatigue - Hands-free steering allows the operator to focus more attention on the equipment control, reducing fatigue and stress and increasing quality and efficiency.

Increase Working Hours - Hands-free steering allows for near perfect applications in reduced visibility caused by heavy fog, dust, or night operation. This allows for faster ground speeds and increased hours of operation.

Collection and Monitoring - GPS, in combination with soil measurements and crop yield information, allows for detailed analysis and mapping identifying potential areas of improvement. This data can also be used with more advanced systems to vary application rates to improve yield.

Properly Maintain EquipmentTractors are a key component to most agricultural operations, yet when it comes to maintaining them, they are often neglected. This can lead to premature wear on critical engine components and shorten their useful life. This can also lead to significant losses in fuel efficiency particularly on older tractors. Tractors should be maintained as specified in there operators manual to get the most out of them. This will help increase their useful life and fuel efficiency while decreasing the number of costly breakdowns that occur during the operating season. This will also increase the power output while minimizing the amount of harmful exhaust emissions released into the atmosphere.

Listed below are some tips on how to properly maintain equipment.

Check tire pressure weekly - Under inflated tires can not only prematurely wear tires giving them a shorter life but can also decrease fuel efficiency by 3 percent. Over inflated tires can cause excessive slip decreasing fuel efficiency by 3 percent. Check tire pressures weekly as

pressure can change when exposed to work intensive tasks. Check your operator’s manual for correct inflation pressures.

Check and replace oil and fuel filters seasonally - Clogged or dirty filters can not only harm the engine but also decrease fuel efficiency by up to 5 percent. Replace filters as recommended by operators manual.

Check and clean air filters weekly and replace as needed - In some extreme cases, a dirty air filter can decrease fuel efficiency by up to 20 percent. Check, clean and change air filters as recommended by operators manual.

Check ballast weight on implement change - Properly ballast the tractor to reduce slip, power hop and weight. Excessive weight can increase fuel consumption so it is important to reduce weight as much possible while still maintaining good traction, balance and handling characteristics. Tire slippage should be kept to a minimum, between 5 an 15 percent for work intensive tasks is usually good. Check operator’s manual for more details.

Check thermostat is properly functioning - Engines are most efficient when operating with a water temperature between 165 and 180 degrees F. Fuel efficiency can decrease by 25 percent when operating at 100 degrees F. Make sure tractors thermostats are operating correctly and not over or under cooling the engine.

Use engine block heaters before operation - Using engine block heaters that are set on timers to preheat the engine a couple hours before use can reduce wear on key engine components. Most engine wear happens on start up when the engine and fluids are cold. By heating the engine prior to start up, this wear can be avoided extending the useful life of the engine and keeping failures to minimum.

Check spark plugs - On gas models a fouled spark plug can decrease fuel efficiency between 10 and 15 percent. It is important to check all plugs regularly for a strong spark.

Check proper fitting fuel caps - Improper fitting fuel caps can leak fuel. Make sure the fuel cap is properly tightened after every fill up and replace any broken or worn seals.

Avoid excessive road use - Excessive road use can prematurely wear tires giving them a shorter life. Worn tires also get significantly less traction reducing fuel efficiency.

Use correct size tractor for implement - Using an over sized tractor for the implement can reduce fuel efficiency. If the tractor can be significantly throttled down while still performing the task it is a good sign that it is over sized and a smaller tractor should be used.

Upgrade to more efficient models when replacing tractor - When buying a new tractor it is best to buy an efficient one even if it cost slightly more. The increase in efficiency will quickly pay for itself.

Avoid quick starts - Engines need to warm up to operating temperatures before worked excessively to reduce the wear on the engine. This is because the engine oil needs to be warmed up and circulated throughout the engine to give proper lubrication. Quick starts don't give the engine enough time to do this causing excessive wear.

Have wheels aligned and balanced - Properly aligned and balanced tires decrease the overall rolling resistance of the tractor increasing fuel efficiency. Check your operator’s manual for more details.

GreenhousesGreenhouses account for a substantial portion of a typical nurseries energy consumption.  Therefore it is important to find ways to conserve electricity, fuel and water while reducing associated operating costs.

Optimize Solar PotentialOne of the most critical factors affecting the amount of solar heat a greenhouse is able to absorb is its orientation in relation with the sun's line of movement. Depending on your location and type of greenhouse this orientation will either be North to South or East to West. Each orientation has its own benefits and should be determined by your facilities needs.

Factors to consider when determining the correct orientation are as follows.

Location - Geographic locations more than 30 degrees from the equator suffer from a seasonal reduction in solar radiation availability and should orient greenhouse in the East to West orientation to maximize solar absorption. Geographic locations closer to the equator should use the North to South orientation to maximize solar absorption.

Climate - During the winter the sun sits lower in the sky decreasing the light intensity and length, making the East to West orientation ideal for absorbing the most solar heat available. If cold winters and high heating costs are a concern than the East to West orientation is best.

Light Uniformity - The North to South orientation will provide a more uniform light distribution than an East to West orientation in most cases. This can be solved by adding reflective materials to the North facing walls of East to West oriented greenhouses.

While it is not cost effective to change a already existing greenhouses orientation these factors should be considered when installing a new greenhouse.

InsulationUn-insulated or poorly insulated walls are a significant source of energy loss in any greenhouse. Temperature differentials between the walls and surroundings act as a driving force for the heat transfer between these bodies. The rate of this heat transfer is directly proportional to the magnitude of the temperature differential. This differential creates a steady energy stream exiting the greenhouse, requiring the boiler to consume more energy to replenish the lost heat. Insulating greenhouse walls will decrease this rate of heat transfer thus saving energy and increasing available heat from heaters, improving the efficiency of the system.

Effective use of insulation can significantly reduce heating costs by reducing heat lost through the greenhouse exterior. It can also help increase the greenhouses solar absorption effectiveness especially in units with solar heat storage systems. Insulation comes in a large variety of forms depending on its intended area of use.

Listed below are some common insulation areas and materials.

Glazing Insulation - The majority of heat loss in greenhouses comes from the glazing. The key is to find a glazing that has a high light transmission value as to let the most light in while also having a high insulating value. One of the most effective ways to accomplish this is using double layers separated by an air gap. This allows a high level of light transmission while also providing

adequate insulation. Many new types of materials have been developed in recent years that optimize both of these requirements. The most dominant material of choice is a plastic as it provides adequate light transmission and excellent insulation characteristics. Factor to consider while determining the optimum glazing are as follows:

o Slope - Greenhouse glazing should be properly sloped to absorb the maximum amount of solar radiation. As a general rule of thumb the slope of the glazing should be 10 to 15 degrees more than the geographic latitude.

o Material Type - Depending on your requirements there are many different types of materials available. The most durable is double layered glass as it can last for over 50 years or until broken. The most energy efficient glazing is polyethylene based films, they require minimal structural support and have excellent insulation characteristics when layered but must be replaced every 3 to 5 years.

Walls Insulation – Often walls (especially north facing walls) can be insulated up to a certain height with non transparent materials that are much more effective than typical glazing materials. This can reduce heat loss through walls while maintain the same solar gain input from the roof.

Floor Insulation - Greenhouse floors typically are constructed of masonry, brick or flagstone which act as excellent conductors. It is recommended that these materials be insulated from the ground by a layer of rigid insulation as to avoid heat loss to the ground.

Thermal CurtainDuring the night, heat from inside the greenhouse is absorbed into the cold night sky. This heat loss can be reduced by up to 90 percent by using thick polystyrene insulation that is rolled over the exterior of the greenhouse during nights. This is typically hard to implement due to structural concerns and increased labor. A more common method uses thinner curtains in the greenhouse interior that can be either manual deployed for smaller operations or motorized and automated for large scale facilities. Thinner curtains can yield 20 to 50 percent savings depending on material and installation methods.

Thermal StorageSolar heat storage is a method used in solar greenhouses to maintain warmer temperatures during cold nights and colder temperatures during hot summer days. The most commonly utilized method is to place barrels of water in direct sunlight inside the greenhouse to absorb the solar heat and store it for later use. There are many different methods used to achieve different levels of storage. Listed below are some common methods used for heat storage

Water - The simplest method of heat storage is using 55 gallon drums full of water placed along the north wall of East to West oriented greenhouses. These drums will absorb heat during the day keeping the greenhouse cooler and release the heat at night keeping the greenhouse warmer. These drums should be painted black to maximize heat absorption and be placed so they do not contact the walls as to reduce heat loss. While 55 gallons drums work fairly effectively a more efficient alternative is to use smaller containers or vertically mounted tubes. This is especially true in areas that frequently have cloudy conditions.

Phase Changing Materials - Instead of water, phase changing materials can be a more effective means of heat storage. While these materials are generally much more expensive than conventional methods, they are 5 to 14 times more effective at storing heat than water. This is particularly useful when floor space is limited and conventional methods won't fit.

Trombe Walls - These are low lying walls on the south facing side of the greenhouse usually constructed from glass and black masonry bricks. Heat passes through the glass and is absorbed by the black masonry while natural convection circulates the hot air through the rest of the greenhouse.

Space UtilizationAisles are needed inside greenhouses so that workers can freely move about performing daily activities. One method that can increase space use up to 90 percent is or movable benches. Movable benches can be moved side to side creating or filling up aisles, typically system are designed so that only one aisle is open at any given time. This can allow either more product to be produced at a given time or the consolidation of greenhouses so that some may be turned off.

Listed below are some tips on space utilization in greenhouses.

Increase space utilization to 80% - 90% with peninsular or movable benches. Install multi-level racks for crops that don't require high light levels. Grow a crop of hanging baskets on overhead rails or truss-mounted conveyor system. A roll-out bench system can double growing space. Top level plants are moved outside during the

day.

Efficient Heating SystemMany different systems exist for heating greenhouse during the winter, some more efficient than others. A common method for heating uses multiple small direct fire heaters to heat and circulate the air within a greenhouse. A more efficient method uses a pipes circulating hot water either below the bench or just above the ground depending on crop type and growing style. This method heats the root zone directly instead of the surrounding air, improving crop production while reducing heating loads. Commonly this reduces greenhouse air temperature while maintaining plant temperature.

Listed below are some situations where bench or floor heating should be considered.

Greenhouses feature benches yet heat with direct fire heaters. These can be easily and cost effectively retrofitted to bench top heating.

Greenhouses that grow crops directly in the soil can be retrofitted to above floor heating systems that wrap around crop rows.

Grain/Nut DyersMost commonly used to dry tree nuts, dryers can represent a substantial portion of an operations electrical and gas bills. It is therefore important to maximize system efficiency and reduce associated energy costs.

PID Moisture Sensing ControlMost operations run their dryer fans at full speed during the entire drying process. This is unnecessary once surface moisture has been dried as it takes time for internal moisture to migrate to the surface. A drying process should consist of two basic stages: (1) Maximum fan output; where surface moisture is removed from the material by applying a large air flow and (2) Reduced fan speed stage; the heat of the dryer bed is increased by lowering fan output in incremental steps, this draws moisture from the interior

of the material. This optimized method of drying requires the use of a VSD on fans integrated with PID controller and moisture sensors.

Listed below are some situations where moisture sensing control should be considered.

Fans operate at full speed no matter the dryer load or material conditions.

Solar DryingIn some instances some or all of a drying process can be performed through use of solar energy. This can drastically reduce energy consumption but is more labor intensive in most cases. This is especially true in smaller drying process that are only required during summer months.

Dust Collection

Efficient FansSwitching to more efficient blade type is often a cheap method to increase efficiency. Sometimes other modifications to the system must be made in order to accommodate a blade upgrade. A common example is switching to a clean side material handling system to allow higher efficiency airfoil fan blades to be installed reducing energy consumption.

Listed below are some situations where replacing fan blades should be considered.

Fans currently feature radial or radial tip fan blades to perform relatively clean tasks. Dust collection system could be modified to switch from dirty side fans to more efficient clean

side fan styles.

Animal Production SpecificIndustries in the Animal Production subsector raise or fatten animals for the sale of animals or animal products. The subsector comprises establishments, such as ranches, farms, and feedlots primarily engaged in keeping, grazing, breeding, or feeding animals. These animals are kept for the products they produce or for eventual sale. The animals are generally raised in various environments, from total confinement or captivity to feeding on an open range pasture. (NAICS 2007)

Animal Housing VentilationVentilation systems are an important part of any livestock farm. Supplying fresh clean air at the right temperature and humidity can significantly increase animal production. Upgrading to a more efficient system will reduce energy consumption thus reducing associated energy costs while also increasing animal comfort and productivity.

HVLS FansAs fan speed increases so does noise and turbulence lowering efficiency. One solution is to use high-volume, low-speed fans (HVLS), which range in size from 3 to 30 feet. These fans consume much less energy and produce less noise than the typical low-volume, high-speed (LVHS) fans.

Listed below are some situations where HVLS fans should be considered.

LVHS fans are currently used for animal housing ventilation Housing structures has wide open spaces above animals where HVLS fans could fit and be

structurally sound.

Milking OperationsDairies utilize a wide variety of energy intensive systems including thermal and pumping processes.

Milk Pre-CoolerAn in line plate cooler works by using cold well water to partially cool milk before it enters the storage tank. Depending on a number of factors such as temperature and flow rate, milk temperature can be reduced by 30°'s or more. This reduces the load on the refrigeration system compressors decreasing associated energy cost typically between 20 and 30 percent although in some cases as much as 50 percent. Pre coolers also reduce the amount time it takes to cool the milk to storage temperature increasing quality. The warm water coming out of the pre cooler can then be reused for other purposes. Warm water can be reused as pre heated water for the water heater, to heat up the milking parlor room, or used to water livestock. It has been shown that cows prefer warm water to cold water, so they may consume more water thus, producing more milk.

Long Day LightingThe easiest way to increase milk productivity is by using long day lighting.  Studies have shown that leaving barn lighting on for 16 - 18 hours a day can increase milk production by 5 - 16 percent.  This can

be achieved by installing a timer on lights to keep the day lighting as consistent as possible.  The only downside is that lights are on longer increasing energy consumption, and that cows will eat more increasing food costs.  But in most cases the increase in milk productivity will significantly outweigh the associated cost increases.  Upgrading lighting to more efficient systems can be a cost effective way to reduce the increase in lighting costs although it may not be necessary in some cases.

Insulate Milk TankA portion of the energy used to cool the milk tank is lost to the room due to a temperature difference between the shell and the ambient temperature. Energy losses can be reduced 12% by adding paint on food grade insulation in addition to the insulation created by the trapped layer of air between the two stainless steel shells. Energy savings will result by reducing the amount of energy required to maintain the internal temperature of the tank.

VSD Vacuum PumpVacuum pumps are one of the biggest energy consumers on a dairy. They are designed and sized to meet the maximum demand during the initial pull down and when all milking units are being used. Most of the time the vacuum pump doesn't need to be pulling such a large vacuum. Installing a VSD allows the motor to idle back when less than full power is required. This is a more efficient method than leaving the motor running full speed and can reduce your vacuum pump energy consumption by 40 to 80 percent.