Encourage Replacement of In-Service Standard Efficiency Motors with Premium Efficiency Models
Induction Motors: Premium Efficiency vs. Standard and Energy Efficient
Encourage replacement of in-service industrial motors with NEMA Premium®- or Enhanced-efficiency motors that are 2% to 9% more efficient than standard motors.
Synopsis:
The National Electrical Manufacturers Association (NEMA) adopted a voluntary NEMA Premium® efficiency motor standard in 2001, which applies to most 1- to 500-hp motors operating at 600 Volts or less. Under the Energy Independence and Security Act of 2007 (EISA), the mandatory minimum nominal efficiency for general purpose motors with a power output from 1 to 200 hp was raised to the NEMA Premium level. (DOE issued a NOPR to extend this to motors up to 500 hp in December, 2013). This mandatory minimum efficiency requirement applies to motors purchased alone, as part of an equipment package, or imported into the country. However, unfortunately, EISA does not apply to motors that are in service, and therefore plant operators are not mandated to replace operating standard-efficiency motors.
Facilities built after 1997 tend to have energy-efficient motors due to mandatory minimum full-load efficiency requirements. Older industrial plants tend to operate older, standard efficiency motors. Assessments conducted between 2005 and 2011 at 123 industrial plants indicate that over 70% of operating motors are of standard efficiency design. Failed standard efficiency motors from 25 hp to 50 hp are typically rewound and returned to service due to excessive simple payback.
NEMA Premium efficiency motors are available in all low-voltage hp ratings. Replacing a 200-hp standard efficiency motor with a NEMA Premium motor can save 34,520 kWh/year (at 75% load and in operation for 8,000 hours/year). Only a handful of utilities offer incentives ($3,300 for a 100-hp motor) large enough to make it cost effective to replace operating standard efficiency motors with Premium-efficiency or Enhanced-efficiency (one percentage point greater than Premium) motors, but most do not.
Energy Savings: 4%
Energy Savings Rating: Approved Measure
What's this?
Level | Status | Description |
1 | Concept not validated | Claims of energy savings may not be credible due to lack of documentation or validation by unbiased experts. |
2 | Concept validated: | An unbiased expert has validated efficiency concepts through technical review and calculations based on engineering principles. |
3 | Limited assessment | An unbiased expert has measured technology characteristics and factors of energy use through one or more tests in typical applications with a clear baseline. |
4 | Extensive assessment | Additional testing in relevant applications and environments has increased knowledge of performance across a broad range of products, applications, and system conditions. |
5 | Comprehensive analysis | Results of lab and field tests have been used to develop methods for reliable prediction of performance across the range of intended applications. |
6 | Approved measure | Protocols for technology application are established and approved. |
Simple Payback is one tool used to estimate the cost-effectiveness of a proposed investment, such as the investment in an energy efficient technology. Simple payback indicates how many years it will take for the initial investment to "pay itself back." The basic formula for calculating a simple payback is:
Simple Payback = Incremental First Cost / Annual Savings
The Incremental Cost is determined by subtracting the Baseline First Cost from the Measure First Cost.
For New Construction, the Baseline First Cost is the cost to purchase the standard practice technology. The Measure First Cost is the cost of the alternative, more energy efficienct technology. Installation costs are not included, as it is assumed that installation costs are approximately the same for the Baseline and the Emerging Technology.
For Retrofit scenarios, the Baseline First Cost is $0, since the baseline scenario is to leave the existing equipment in place. The Emerging Technology First Cost is the Measure First Cost plus Installation Cost (the cost of the replacement technology, plus the labor cost to install it). Retrofit scenarios generally have a higher First Cost and longer Simple Paybacks than New Construction scenarios.
Simple Paybacks are called "simple" because they do not include details such as the time value of money or inflation, and often do not include operations and maintenance (O&M) costs or end-of-life disposal costs. However, they can still provide a powerful tool for a quick assessment of a proposed measure. These paybacks are rough estimates based upon best available data, and should be treated with caution. For major financial decisions, it is suggested that a full Lifecycle Cost Analysis be performed which includes the unique details of your situation.
The energy savings estimates are based upon an electric rate of $.09/kWh, and are calculated by comparing the range of estimated energy savings to the baseline energy use. For most technologies, this results in "Typical," "Fast" and "Slow" payback estimates, corresponding with the "Typical," "High" and "Low" estimates of energy savings, respectively.