ANSI/AMCA Standard 208, Calculation of the Fan Energy Index, can be downloaded at no cost from the online store of Air Movement and Control Association (AMCA) International Inc. through the end of 2019. AMCA opted to release it for free to help disseminate the information to fan builders and buyers.

The standard defines the calculation method for the fan energy index (FEI), which is an energy efficiency metric for fans inclusive of motors and drives. This metric provides a consistent basis to compare fan energy performance across fan types and sizes at a given fan duty point.

Fan specifiers can use FEI to understand and communicate the fan efficiency design intent. Legislative or regulatory bodies can use FEI to define the energy efficiency requirements of fans.

The scope includes all fan and motor sizes and all applications, including fans with fan air performance based on tests in accordance with one of the following fan test standards: ANSI/AMCA Standard 210, ANSI/AMCA Standard 230, ANSI/AMCA Standard 250, ANSI/AMCA Standard 260, ISO 5801, or ISO 13350. All other fans are excluded (including air curtain units that are tested in accordance with ANSI/AMCA Standard 220).The ratio of the electrical power of a reference fan to the electrical power of an actual fan, both calculated at a given airflow and pressure duty point, FEI “levels the playing field,” enabling meaningful comparisons of many different fan types, says AMCA.

The standard was developed by AMCA and its members to replace fan efficiency grade (FEG), the metric introduced in 2010 in ANSI/AMCA Standard 205, Energy Efficiency Classification for Fans.