AMCA developed the fan energy index (FEI) in response to the 2013 U.S. Department of Energy (DOE) rulemaking, which preferred a metric based on electrical power consumption, different from the fan efficiency grade (FEG) metric.
FEI
measures the efficiency of the entire fan system, including the fan, motor, and
drive, instead of just the fan itself. It sets an efficiency and power baseline
that changes with airflow and pressure and can be applied to most commercial
and industrial fans and blowers.
This
index is calculated using data from laboratory performance tests and can be
found in manufacturer sizing software and product catalogs. Unlike other
metrics, FEI does not set a peak-efficiency threshold but establishes a
"range of compliant operations." This means that FEI optimizes fan,
motor, and drive selections for the specific conditions under which they will
operate.
Benefits
Clarity for Buyers and specifiers
FEG ratings cover a range of sizes for a particular fan model, which can hide the lower actual efficiencies of smaller fans. For instance, the FEG 67 rating applies to a range of efficiencies, from approximately 45% to 65%, depending on the impeller diameter. Generally, larger fans are more efficient. To address this, designers need to use a sizing window to encourage fan selections to larger diameters. FEI ratings solve this problem by providing values that accurately reflect the actual efficiency of a fan.
Application Flexibility
Manufacturer software offers compliant fans of various types, sizes, materials, and motor/drive combinations when a designer inputs a fan selection or duty point. This makes cost-benefit analyses for fans with higher FEI ratings easier.
Simpler Design and Enforcement
FEG requires a sizing window of "15 percentage points from peak total efficiency." This means that fans must be rated for total efficiency although static-pressure ratings are more commonly used. For every fan that is being covered, designers must document it, and code officials must check for compliance. If the sizing window is ignored, smaller fan sizes will likely be selected because of lower costs, but this will result in higher energy consumption and life-cycle costs. On the other hand, FEI works for both static and total efficiency and eliminates the cumbersome window.
Greater Energy Saving
FEI saves energy compared to FEG by making it easier to use and enforce, and by encouraging the use of more efficient fan types, sizes, and motor/drive combinations.
State Energy Codes & Updates
The latest editions of the U.S. model energy codes and standards have already made the transition to FEI, and it will be implemented as they are adopted.
For jurisdictions that adopt earlier editions
of model codes, AMCA requests that they replace FEG provisions with FEI
provisions.
If
your jurisdiction follows the IECC, consider Florida - 2020 Florida Building Code, Energy Conservation, 7th edition -
Section C403.2.12.3 Fan Efficiency. In doing so, they replaced the
fan-efficiency section with the language in the 2021 IECC. View the IECC underlined-strikeout
template.
If
your area is updating to the 2013 or 2016 edition of ANSI/ASHRAE/IES 90.1, consider
swapping the fan-efficiency section with the corresponding section in the 2019
edition. Oregon 2021 Oregon Efficiency Specialty Code (OEESC). Make changes to energy
codes View the ASHRAE 90.1 underlined-strikeout
template.
Resources
Codes & Standards
- ANSI/AMCA Standard 205, Energy Efficiency Classification for Fans
- ANSI/AMCA Standard 207-17, Fan System Efficiency and Fan System Input Power Calculation
- ANSI/AMCA Standard 208-18, Calculating Fan Energy Index
- AMCA Publication 211-13 (Rev. 10-18), Certified Ratings Program Product Rating Manual for Fan Air Performance
- ANSI/ASHRAE/IES 90.1 Standard 90.1: Energy Standard for Buildings Except Low-Rise Residential Buildings
- IgCC® — Powered by ANSI/ASHRAE/ICC/USGBC/IES Standard 189.1: A Comprehensive Solution for High-Performance Buildings
- CEC: Building Energy-Efficiency Standards-Title 24
- CEC: Appliance Efficiency Regulations – Title 20
- 2021 International Energy Conservation Code (IECC)
- EERE Appliance and Equipment Standards Pogram
- Energy Conversation Standards for Commercial and Industrial Fans and Blowers
- 2016-11-01 EERE Conversation Standards for Commercial and Industrial Fans and Blowers
Presentations & Videos
Articles & Papers
- Introducing Ceiling Fan Energy Index
- FEI for Energy-Saving Fan Selection – pages 10-17
- Two New Metrics for Fan System Efficiency: Fan Energy Index and Fan Electrical Power
Certified Ratings Program
The AMCA Certified Ratings Program (CRP) assures buyers, specifiers, and users that a product line has been thoroughly tested and rated in compliance with rigorous test standards and rating requirements, enabling the selection of the appropriate air system components that fulfill required performance specifications.
Specify AMCA-certified FEI ratings whenever possible, even if not required by code, as manufacturers should exercise great care when updating their sizing/selection software to accommodate the motor and drive combinations available across fan types and sizes. View CRP fan energy index licensed products by company.
Air Movement and Control Association International, Inc.