Impact of Minimum Fan Efficiency Grade Dr. John Cermak Executive Vice President ACME Engineering and Manufacturing Corp.
Learning Objec-ves 1. Describe Fan Efficiency Grade (FEG) 2. Describe the use and application of FEG 3. Explain FEG for selection of efficient fan 4. Provide overview of how FEG will be used in the fan industry in the very near future 5. Explain how standard and regulatory authorities will utilize FEG for setting requirements 6. Describe the impact of FEG on fan technologies. ASHRAE is a Registered Provider with The American Institute of Architects Continuing Education. Credit earned on completion of this program for non- AIA members are available on request. This program is registered with the AIA/ASHRAE for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related of specific materials, methods, and services will be addressed at the conclusion of this presentation. 2
Four Components for Fan Energy Consump-on Air Power = Air Flow x Fan Total Pressure Responsibility of System Designer Fan Selection Responsibility of System Designer Motor Efficiency Regulated by DOE Fan Efficiency Responsibility of Fan Manufacturer 3
Breakdown Fan pressure drop across the system Fan Selection Root cause of both is using too high air velocities Some maximum limits for air velocities in ducts are subject to regulations IGCC and ASHRAE 90.1 are in public review of the considered rules for selecting fans in the vicinity of their peak efficiency 4
Breakdown Motor Efficiency Efficiency of most motors is regulated by DOE but there is a lot motors not regulated Fan Efficiency Regulation considered by IGCC and ASHRAE 90.1, later possibly by DOE 5
Use of FEG in near future ANSI/AMCA 205-2012 Energy Efficiency Classification for fans Exclusion fans with motor less than 1 hp International Green Construction Code Stand alone supply, return and exhaust fans with motor over 1 hp shall have not less than FEG71 selected within 10% from the fan peak efficiency 6
Using high fan efficiency 7
Using high fan efficiency 8
Using high fan efficiency 9
Using high fan efficiency 10
Use of FEG in near future ASHRAE 90.1 Required minimum FEG 67 Selected within 15% from the fan peak efficiency Excluded: Multiple fans in parallel operation with combine motor power less than 5 hp Fans listed in Table 6.4.1.1 Fans included in equipment bearing a third party certification for air or energy performance Powered wall/roof ventilators (PRV) Fan intended for only in emergency conditions Fans outside of the scope of ANSI/AMCA 205 11
Use of FEG by fan industry AMCA Publication 211 is a certified rating program administrated by AMCA International. Fans having certified FEG can bear the AMCA Label for FEG Now about two dozen fan companies have their products with certified AMCA Label for FEG Fan selection programs used by AMCA International members offer FEG appropriate for the selected products Fan selection programs allow selection of fans from a pool created by the regulatory requirements 12
Use of FEG for regula-on FEG characterize the fan capability for transfer of the energy FEG numbers refer to the level of fan energy efficiency Change the grade by one is change of the energy requirements by 6% Allow for warning of the fan industry for future trends in energy conservation Use of a minimum number of required FEG, possible one If necessary use exclusion 13
Use of FEG for regula-on Regulation using FEG would lead into changes in fan technology over a period of time Major issues are expected for non- classic fans, those include other equipment that the fan itself (PRV, laboratory exhaust fans, box (cabinet fans etc.) There can be used exclusions or derated requirements to FEG 14
Classic type fans The air passage of these fans consists from: impeller, inlet bell, housing scroll for centrifugal and cylindrical for axial type impellers 15
Classic Fan Types Centrifugal fans (not FC!!) with scroll housing Vane- axial fans Propeller fans Mixed flow fans with scroll or cylindrical housing and vanes 16
Other Fan Types Plenum fans Cabinet (box) fans In- line centrifugal fans Lab exhaust systems (plume discharge or ejector type) Air curtains 17
Impact of regula-on on fan technologies Initial phase Most of the classic fans meet the requirements but some would need efficiency improvements Selecting larger fans to use their high efficiency would lead to space issues in the packaged air handling equipment Some increase of use speed control of fans 18
Impact of regula-on on fan technologies Second phase With increased FEG some plenum fans and fans with forward curved blades would not be able to keep up possible higher requirements for the space to put the fan in Higher use of centrifugal fans with scroll and vane- axial fans can be expected Increased use of speed control of fans Increased of use of direct driven fans 19
Cordier/Eck Curve Never asked question: What is the efficiency ceiling for fans? The answer is the optimum efficiency curve developed by Bruno Eck in 1962 using the O. Cordier publication (1953) 20
Speed Coefficient Introduction of Speed Coefficient for machines working with fluids in general 21
Cordier/Eck Curve for Fans Linking the Fan Speed Coefficient with the Fan Peak Energy Efficiency allows for estimating the efficiency ceiling for the classic type of fans These fans have a complete aerodynamic setup and yield higher efficiencies than other types of fans The ceiling is not continuous curve 22
Cordier Efficiency Curve for Fans 23
Using tests with best Props 24
Using tests with best Props 25
Using tests with best Props 26
Using tests with best Axials 27
Using tests with best Axials 28
Using tests with best Axials 29
Using tests with best Radials 30
Using tests with best Radials 31
Using tests with best Radials 32
Cordier Curve as an envelope 33
Es-mated current average level 34
Cordier Efficiency Curve The Cordier/Eck curve allows monitoring, evaluation and prediction of fan efficiency ONLY for classic type of fans Other types of fans have efficiency lower, sometimes significantly, by 15 to 20% With every step up in efficiency the achievement is more difficult and increases the cost of the fan 35
Summary The first steps in regulation of fan efficiency have already made The initial energy savings are coming for using the fans close to the peak of their energy efficiency FEG classification is already wildly implemented by fan manufacturers Short term impact of the fan technology is moderate Long term impact would lead to eliminating of use some non- classic types of fans 36
QUESTIONS? 37