High-Efficiency Motors
alternative practice names:
Electronically Commutated Motor (ECM); EC Motors; NEMA Premium Efficiency Motor; Permanent Magnet Alternating Current Motor (PMAC)
Motors are used on dairy farms for various operations including ventilation, milk harvest, manure management, feed management, and irrigation. There are various types of commercially available motors that include shaded pole, alternating current induction, permanent split capacitor (PSC), electronically commutated (EC). These motor technologies vary widely in their size range and efficiency, which is measured by the amount of energy required by a motor to deliver the rated power to the shaft.
Motor efficiency is typically reported as a percentage out of 100, where a higher percentage means a higher motor efficiency. Motor size availability and controllability with variable frequency drives vary with each motor technology. In some cases, motors on dairy farms do not have a sufficient annual runtime to justify replacement with a higher efficiency model because the payback period would be too long. In other cases, such as with fans, or motors that run over 2,500 hours per year, replacing an existing motor with a high-efficiency model may be justified.
When used, in what regions in the U.S. is the practice found:
Northwest, West, Upper Midwest, Southwest, Northeast, Southeast
FARM SIZE
When used, typically found on farms of the following sizes:
All Sizes
Practice Benefits
Increased profitability: The main benefit of installing high-efficiency motors is a reduction in electricity costs. Certain high-efficiency motors, such as EC motors, can allow for easier control of motor speed without the use of expensive external controllers, which can result in cost savings. Additionally, high-efficiency motors are often manufactured with more rigorous standards, which can result in a longer useful life and lower maintenance costs.
Implementation Insights
Site-specific or Farm-specific requirements
Farm compatibility: Commercially available sizes and types of high-efficiency motors vary depending on the motor application on the farm. For motors that are attached to pumps or controlled by variable frequency drives (VFDs), it is important to check with the motor vendor for compatibility with the existing or planned equipment.
Environmental conditions: If a motor is operating in wet or dusty conditions, it is critical to select motors with adequate housing (e.g. IP65 certified), which is not available for all motor models.
Required Capital Expenditures (CapEx)
High-efficiency motor: The primary expense of this practice is the high-efficiency motor itself, along with the labor required to install it. It is critical to work with an experienced motor vendor to ensure that the motor being installed (whether new construction or retrofit) is properly sized for the application to avoid unnecessary up-front expenses and suboptimal performance.
Motor controls and sensors: Additional capital expenditures can include motor controls, such as a variable frequency drive (VFD), and associated sensors, if applicable.
Required Operational Expenditures (OpEx)
Maintenance: Ongoing maintenance costs for high-efficiency motors are generally low, assuming the motor is properly sized and is sealed if in a wet or dusty environment. Motors should be inspected and cleaned regularly in accordance with manufacturer guidelines. If motors have V-belts, they should be replaced with notched belts or synchronous belts to improve efficiency.
Implementation Considerations
Motor selection: In general, the most efficient motor technology available for replacing motors 1.5 horsepower or less will be an EC motor. For larger horsepower applications, there are motors designated by the National Electrical Manufacturers Association (NEMA) as “premium efficiency” based on their standard, which are typically the highest efficiency alternative and are available up to at least 1,000 horsepower. Some motors also have an efficiency rating from the International Electromechanical Commission (IEC), which range from IE1 to IE5, where the higher numbers correspond to higher efficiencies. IE3 motors are equivalent to NEMA Premium Efficiency motors.
Payback period: When deciding on whether to install a high-efficiency motor such as a NEMA Premium Efficiency or IE3+ motor, it is critical to consider the runtime of the motor and determine whether the simple payback period is shorter than the useful life of the motor (typically 10-20 years). The payback period will be shorter for motors that are larger and have higher annual runtime hours, and it typically only makes sense to replace an existing motor with a high-efficiency model if the existing motor is at the end of its useful life or runs for at least 2,500 hours per year. It is best to work with a qualified motor vendor or third-party energy analyst to evaluate motor upgrade opportunities to prioritize the farm’s capital investments. The fastest payback period for high-efficiency motor installations is usually found with vacuum pump motors and fan motors, both of which can be coupled with motor controls to further reduce energy inputs. In the case of fan motors, the efficiency of the motor is reflected in the fan efficiency (reported as CFM/Watt). The most efficient dairy circulation and exhaust fans today use EC motors.
Financial Considerations and Revenue Streams
FEDERAL COST-SHARE AND CONSERVATION FUNDING
Funding is available for this practice through USDA's Natural Resources Conservation Service (NRCS) Environmental Quality Incentives Program (EQIP) On-Farm Energy Initiative.
Related EQIP Practice Standard: Energy Efficient Agricultural Operation (374).
Notes:
An Agricultural Energy Management Plan (AgEMP), or other qualifying energy audit, needs to be completed before applying for EQIP assistance.
Check with the local NRCS office on payment rates and practice requirements relevant to your location.
The USDA Rural Development Rural Energy for America Program (REAP) also offers competitive grants and loan guarantees for installing energy efficiency projects.
OTHER CONSERVATION FUNDING
Incentives and rebates for high-efficiency motors and motor controls are sometimes available through the farm’s electric utility company. Utility rebate programs usually pay rebates based on a per-horsepower basis, and often require that motors are NEMA Premium Efficiency certified and/or meet a minimum efficiency level.
FINANCIAL RESOURCES, TOOLS, AND CASE STUDIES
Additional Resources
Article: Energy Efficiency of Electric Motors on the Farm (Farm Energy, Extension Foundation)
Article: Electronically Commutated Motors are a Superior Choice for Dairy Ventilation Fans (inBarn)
Factsheet: Replace V-Belts with Notched or Synchronous Belt Drives (U.S. Dept of Energy)
Guidebook: Dairy Energy Best Practices Guidebook (NYSERDA and EnSave; see pages 19-21)
Environmental Impacts
REDUCES FARM GREENHOUSE GAS FOOTPRINT
Improving energy use efficiency reduces a farm's greenhouse gas (GHG) footprint. Since energy production typically involves processes that emit greenhouse gases like carbon dioxide and methane, cutting energy use directly lowers the GHG footprint of the farm.
Alignment with FARM Program
FARM Environmental Stewardship (ES) V2-V3 Alignment
FARM ES captures a farm's energy usage and calculates the associated GHG emissions based on regional energy production and transmission averages. Any practice that reduces farm energy consumption will directly lower the farm's GHG footprint. The reduction in GHG emissions is particularly pronounced in regions where a larger proportion of energy is derived from coal, natural gas, or other fossil fuel sources, as these energy types have higher carbon footprints compared to renewable energy sources.
Contents
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
Motors are used on dairy farms for various operations including ventilation, milk harvest, manure management, feed management, and irrigation. There are various types of commercially available motors that include shaded pole, alternating current induction, permanent split capacitor (PSC), electronically commutated (EC). These motor technologies vary widely in their size range and efficiency, which is measured by the amount of energy required by a motor to deliver the rated power to the shaft.
Motor efficiency is typically reported as a percentage out of 100, where a higher percentage means a higher motor efficiency. Motor size availability and controllability with variable frequency drives vary with each motor technology. In some cases, motors on dairy farms do not have a sufficient annual runtime to justify replacement with a higher efficiency model because the payback period would be too long. In other cases, such as with fans, or motors that run over 2,500 hours per year, replacing an existing motor with a high-efficiency model may be justified.
Practices and technologies
High-Efficiency Motors
alternative practice name:
Electronically Commutated Motor (ECM); EC Motors; NEMA Premium Efficiency Motor; Permanent Magnet Alternating Current Motor (PMAC)
REGIONALITY
When used, in what regions in the U.S. is the practice found:
Northwest, West, Upper Midwest, Southwest, Northeast, Southeast
COMPARABLE FARM SIZE
When used, typically found on farms of the following sizes:
0 - 100 cows, 100 - 500 cows, 500 - 2500 cows, 2500 - 5000 cows, Over 5000 cows
Practice Benefits
Increased profitability: The main benefit of installing high-efficiency motors is a reduction in electricity costs. Certain high-efficiency motors, such as EC motors, can allow for easier control of motor speed without the use of expensive external controllers, which can result in cost savings. Additionally, high-efficiency motors are often manufactured with more rigorous standards, which can result in a longer useful life and lower maintenance costs.
Implementation Insights
Site-specific or Farm-specific requirements
Farm compatibility: Commercially available sizes and types of high-efficiency motors vary depending on the motor application on the farm. For motors that are attached to pumps or controlled by variable frequency drives (VFDs), it is important to check with the motor vendor for compatibility with the existing or planned equipment.
Environmental conditions: If a motor is operating in wet or dusty conditions, it is critical to select motors with adequate housing (e.g. IP65 certified), which is not available for all motor models.
Required Capital Expenditures (CapEx)
High-efficiency motor: The primary expense of this practice is the high-efficiency motor itself, along with the labor required to install it. It is critical to work with an experienced motor vendor to ensure that the motor being installed (whether new construction or retrofit) is properly sized for the application to avoid unnecessary up-front expenses and suboptimal performance.
Motor controls and sensors: Additional capital expenditures can include motor controls, such as a variable frequency drive (VFD), and associated sensors, if applicable.
Required Operational Expenditures (OpEx)
Maintenance: Ongoing maintenance costs for high-efficiency motors are generally low, assuming the motor is properly sized and is sealed if in a wet or dusty environment. Motors should be inspected and cleaned regularly in accordance with manufacturer guidelines. If motors have V-belts, they should be replaced with notched belts or synchronous belts to improve efficiency.
Implementation Considerations
Motor selection: In general, the most efficient motor technology available for replacing motors 1.5 horsepower or less will be an EC motor. For larger horsepower applications, there are motors designated by the National Electrical Manufacturers Association (NEMA) as “premium efficiency” based on their standard, which are typically the highest efficiency alternative and are available up to at least 1,000 horsepower. Some motors also have an efficiency rating from the International Electromechanical Commission (IEC), which range from IE1 to IE5, where the higher numbers correspond to higher efficiencies. IE3 motors are equivalent to NEMA Premium Efficiency motors.
Payback period: When deciding on whether to install a high-efficiency motor such as a NEMA Premium Efficiency or IE3+ motor, it is critical to consider the runtime of the motor and determine whether the simple payback period is shorter than the useful life of the motor (typically 10-20 years). The payback period will be shorter for motors that are larger and have higher annual runtime hours, and it typically only makes sense to replace an existing motor with a high-efficiency model if the existing motor is at the end of its useful life or runs for at least 2,500 hours per year. It is best to work with a qualified motor vendor or third-party energy analyst to evaluate motor upgrade opportunities to prioritize the farm’s capital investments. The fastest payback period for high-efficiency motor installations is usually found with vacuum pump motors and fan motors, both of which can be coupled with motor controls to further reduce energy inputs. In the case of fan motors, the efficiency of the motor is reflected in the fan efficiency (reported as CFM/Watt). The most efficient dairy circulation and exhaust fans today use EC motors.
Financial Considerations and Revenue Streams
FEDERAL COST-SHARE AND CONSERVATION FUNDING
Funding is available for this practice through USDA's Natural Resources Conservation Service (NRCS) Environmental Quality Incentives Program (EQIP) On-Farm Energy Initiative.
Related EQIP Practice Standard: Energy Efficient Agricultural Operation (374).
Notes:
An Agricultural Energy Management Plan (AgEMP), or other qualifying energy audit, needs to be completed before applying for EQIP assistance.
Check with the local NRCS office on payment rates and practice requirements relevant to your location.
The USDA Rural Development Rural Energy for America Program (REAP) also offers competitive grants and loan guarantees for installing energy efficiency projects.
OTHER CONSERVATION FUNDING
Incentives and rebates for high-efficiency motors and motor controls are sometimes available through the farm’s electric utility company. Utility rebate programs usually pay rebates based on a per-horsepower basis, and often require that motors are NEMA Premium Efficiency certified and/or meet a minimum efficiency level.
FINANCIAL RESOURCES, TOOLS, AND CASE STUDIES
Additional Resources
Article: Energy Efficiency of Electric Motors on the Farm (Farm Energy, Extension Foundation)
Article: Electronically Commutated Motors are a Superior Choice for Dairy Ventilation Fans (inBarn)
Factsheet: Replace V-Belts with Notched or Synchronous Belt Drives (U.S. Dept of Energy)
Guidebook: Dairy Energy Best Practices Guidebook (NYSERDA and EnSave; see pages 19-21)
Research
REFerences
REDUCES FARM GREENHOUSE GAS FOOTPRINT
Improving energy use efficiency reduces a farm's greenhouse gas (GHG) footprint. Since energy production typically involves processes that emit greenhouse gases like carbon dioxide and methane, cutting energy use directly lowers the GHG footprint of the farm.
Alignment with FARM Program
FARM Environmental Stewardship (ES) V2-V3 Alignment
FARM ES captures a farm's energy usage and calculates the associated GHG emissions based on regional energy production and transmission averages. Any practice that reduces farm energy consumption will directly lower the farm's GHG footprint. The reduction in GHG emissions is particularly pronounced in regions where a larger proportion of energy is derived from coal, natural gas, or other fossil fuel sources, as these energy types have higher carbon footprints compared to renewable energy sources.