Energy Code and Fan Efficiency: How ASHRAE 90.1 and IECC Codes Changed Fan System Design for Healthcare & Institutional Facilities

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2 Energy Code and Fan Efficiency: How ASHRAE 90.1 and IECC Codes Changed Fan System Design for Healthcare & Institutional Facilities Scott Sevigny, PE Shah Smith & Associates Mike Donovan HTS Texas

3 Agenda ØBackground & History-> Fan Systems ØFan System Efficiency ØHow the Industry Arrived at FEG? ØWhat the Codes & Standards State ØSystem Design Practices What can we do? ØEnergy Code Compliance and Application ØExamples of Fan System Analysis with FEG ØWhat s Next for code and standards development

4 Fan Systems are a big part of Building energy consumption 2.5 QUADS is 450 million barrels of oil or 95M tons of Coal annually Fans 38% Chiller 34% Pumps 23% Tower 5% Annual Energy Usage 60% of energy is moving or transporting BTU around buildings

5 The Last 20 Years? 95+ DBA 100+ DBA 91+ DBA 88+ DBA 80+ DBA 88+ DBA 55% Efficiency (FC Fan*) 78% Efficiency (AF Fan*) *Includes 7% loss for V-belt drive 78% Efficiency (PLENUM FAN) Reliability Improved at the same time 70% Efficiency (Fan Array) BELTS & Sheaves + I bearing 84% Efficiency (Flow Enhancement) ALL IN + motor, vfd, bearing, motor fraction 75% Efficiency (Brushless DC motor) ALL IN

6 AMCA 2010 Tells us smaller diameter fan wheel/impeller is less efficient than larger diameter fan wheel/impeller EFFICIENCY EFFICIENCY

7 NEMA MG tells us smaller motors are less efficient than larger motors Great Reference Document: 4/f15/amo_motors_handbook_web.pdf

8 What is the consumer paying in electricity and what is involved? AHRI 1210 AMCA % 2% 15-40% 5-9% 5-12% POWER IN VFD loss (4-5%) Motor Loss (5-12%) Belt Loss (5-9%) Bearing Loss (2-3%) Fan Aero Loss Power Out 15-40% NEMA MG.1 Input Power AMCA 203 ALL-IN!

Industry Yesterday 1917 NAFM (National Association of Fan Manufacturers)-standard 110 which became AMCA standard 210 1923 Fan Testing for the US Navy Origin of AMCA 210

9 Industry Yesterday 1917 NAFM (National Association of Fan Manufacturers)-standard 110 which became AMCA standard Fan Testing for the US Navy Origin of AMCA AMCA formed (Air Movement and Conditioning Association) 1960 AMCA Standard AMCA (Air Movement and Control Association) ~1985 AMCA 301, 311 research of fan sound

10 DOE NOT HAPPY WITH PROGRESS BY OUR INDUSTRY (CIRCA 2007) In Various Standard Organizations (DOE, ASHRAE, AMCA) Began Looking For a Better Means to Reduce Energy Consumption By Building Fans Regulators (DOE) mount up

11 2007 Fan Efficiency Grade (FEG) Committee is Born ü Simple System to indicate the aerodynamic quality of a fan. ü Based on Fan s Peak total efficiency ü FEG is calculated using airflow, pressure, input power. ü Does NOT account for drive and motor efficiency

12 Adoption Of Fan Efficiency Grades Fan Efficiency Grade (FEG) Committee is Born AMCA 205-Energy Efficiency Classification for Fans Published 2012 AMCA 205 updated and Certified by ANSI 2013 ANSI/ASHRAE/IES Std Published with AMCA International Energy Conservation Code (IECC) Published 2016 Tx State Energy Conservation Office (SECO) Adopts: ASHRAE /2015 IECC

13 ANSI/ASHRAE/IES Std Chapter 6 Fan System Power and Efficiency This allows Three Paths for energy Compliance

14 ANSI/ASHRAE/IES Std Chapter 6 Fan System Power and Efficiency This allows Three Paths for energy Compliance 1. Simplified Approach applies only to facilities less than 25,000sqft 2. Prescriptive Path 3. Energy Cost Budget

15 ANSI/ASHRAE/IES Std Chapter 6 Fan System Power and Efficiency This allows Three Paths for energy Compliance 1. Simplified Approach applies only to facilities less than 25,000sqft 2. Prescriptive Path 3. Energy Cost Budget

16 ANSI/ASHRAE/IES Std Chapter 6 Fan System Power and Efficiency ü FEG Not Applicable ü Full Energy Model REQUIRED ü Goal: balance overall Energy use Ø Ø Ø Ø Ø Envelope, HVAC, Lighting, Misc Power Infrastructure, Domestic Water Heating. ü Economic($$) Comparison: Design to be lower cost than Prescriptive Bldg

17 2015 International Energy Code (IECC) what do we do? 3 Choices 1. Comply with ANSI/ASHRAE/IES Std

18 2015 International Energy Code (IECC) what do we do? 3 Choices 1. Comply with ANSI/ASHRAE/IES Std Comply with Mandatory/Prescriptive Requirements

19 2015 International Energy Code (IECC) what do we do? 3 Choices 1. Comply with ANSI/ASHRAE/IES Std Comply with Mandatory/Prescriptive Requirements 3. Comply with Mandatory Requirements and be 85% or less than energy cost Resulting from Option 2.

20 2015 International Energy Code (IECC) what do we do? 3 Choices 1. Comply with ANSI/ASHRAE/IES Std Comply with Mandatory/Prescriptive Requirements 3. Comply with Mandatory Requirements and be 85% or less than energy cost Resulting from Option 2. Choices 2 and 3 require Compliance with FEG

21 2015 IECC and ANSI/ASHRAE/IES Std SECO mandates IECC compliance statewide for all jurisdictions, NOT just state funded buildings as of 2016

22 2015 IECC and ANSI/ASHRAE/IES Std SECO mandates IECC compliance statewide for all jurisdictions, NOT just state funded buildings as of 2016 Conclusion Texas State Law says we need to pay attention to FEG OR do an energy model

23 Engineering Design Approach Minimize Fan Pressure 1. Size duct conservatively 2. Return Air Path 3. Low face velocity Air Handling units at coils, filters ( FPM) Select efficient fans 1. Trend towards plenum fans for flexibility of discharge and shorter air handler lengths 2. Direct Drive (Beware of 1200RPM Motor Selections!) 3. Fan Arrays (Reliability vs Redundancy) 4. Larger diameter wheels turning slower Mechanical Rooms larger, But Energy Bills SMALLER

24 Engineering Design Approach 1. Once the design is somewhat set. Go back and check your energy code compliance 2. AT SSA, we calculate bhp/cfm via spreadsheets

25 BHP(Brake Horsepower) /CFM(Cubic Feet Per Minute) Example STEM Building

26 Engineering Design Approach 1. Once the design is somewhat set. Go back and check your energy code compliance 2. AT SSA, we calculate bhp/cfm via spreadsheets a. Use the various allowance for pressure drop that is included in the standard

27 ANSI/ASHRAE/IES Std Chapter 6 Fan System Power and Efficiency

28 Engineering Design Approach 1. Once the design is somewhat set. Go back and check your energy code compliance 2. AT SSA, we calculate bhp/cfm via spreadsheets a. Use the various allowance for pressure drop that is included in the standard b. Check for FEG compliance if using the prescriptive path with equipment selections

29 Fan Manufacturer Sample Selection Software

30 1. Don t Forget your Submittal - follow thru and watch what the contractor proposes to buy 2. Check the fans for certification in the field. The fans shall bear both the following labels: Engineering Design Approach

31 Is Fan Efficiency Grade (FEG) the bulletproof Answer?

32 ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67* Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67 Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): Flow: 20,000 cfm (9.4 m3/s) Pressure: 6 in-wg (1.5 kpa) Selection Efficiency: 80% FEG: 85 Fan diameter: 30 (DWDI-AF) BHP: 24.2 hp (18.1 kw) SFP: 1.2 hp/kcfm FEG: 85 PASS Flow: 20,000 cfm (9.4 m3/s) Pressure: 4 in-wg (1.0 kpa) Selection Efficiency: 58% FEG: 63 Fan diameter: 27 (DWDI-FC) BHP: 22.1 hp (16.5 kw) SFP: 1.1 hp/kcfm X FEG: 63 FAIL ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67 Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67 Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): Flow: 20,000 cfm (9.4 m3/s) Pressure: 6 in-wg (1.5 kpa) Selection Efficiency: 72% FEG: 85 Fan diameter: 24.5 (DWDI-AF) BHP: 27.0 hp (20.1 kw) X SFP: 1.35 hp/kcfm FEG: 85 FAIL Flow: 20,000 cfm (9.4 m3/s) Pressure: 8 in-wg (2.0 kpa) Selection Efficiency: 82% FEG: 85 Fan diameter: 27 (DWDI-AF) BHP: 32.6 hp (24.3 kw) X SFP: 1.76 hp/kcfm FEG: 85 FAIL

33 ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67 Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): Flow: 20,000 cfm (9.4 m3/s) Pressure: 6 in-wg (1.5 kpa) Selection Efficiency: 72% FEG: 85 Fan Diameter: 24.5 (DWDI-AF) BHP: 27.0 hp (20.1 kw) X SFP: 1.35 hp/kcfm FEG: 85 FAIL

34 ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67* Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): Flow: 20,000 cfm (9.4 m3/s) Pressure: 6 in-wg (1.5 kpa) Selection Efficiency: 80% FEG: 85 Fan Diameter: 30 (DWDI-AF) BHP: 24.2 hp (18.1 kw) SFP: 1.2 hp/kcfm FEG: 85 PASS ANSWER: Larger Diameter Fan Wheel

Cost of 1.0 BHP (Direct Drive) Cost of Energy = $0.10/kwh 5HP Motor Efficiency = 89.5% 5HP Motors (cost of 1.0 BHP) 24/7 Operation: 50hrs/week: $770 per year $302 per year Quantify in Sq. Ft.

35 Cost of 1.0 BHP (Direct Drive) Cost of Energy = $0.10/kwh 5HP Motor Efficiency = 89.5% 5HP Motors (cost of 1.0 BHP) 24/7 Operation: 50hrs/week: $770 per year $302 per year Quantify in Sq. Ft. 20,000 CFM,6 W.G. 94% motor efficiency FC 58% Efficiency = bhp (1.85 BHP per 1000 sq. ft. Hospital) AF 80% Efficiency bhp (1.2 BHP per 1000 sq.ft. Hospital) Difference = 11.6 bhp (single fan)

36 ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67 Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): Flow: 20,000 cfm (9.4 m3/s) Pressure: 4 in-wg (1.5 kpa) Selection Efficiency: 58% FEG: 63 Fan Diameter: 27 (DWDI-FC) BHP: 22.1 hp (16.5 kw) SFP: 1.1 hp/kcfm X FEG: 63 FAIL

37 ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67 Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): Flow: 20,000 cfm (9.4 m3/s) Pressure: 4 in-wg (1.5 kpa) Selection Efficiency: 67% FEG: 80 Fan Diameter: 24.5 (DWDI-AF) BHP: 21.1 hp (16.1 kw) SFP: 1.05 hp/kcfm FEG: 80 PASS *Changed to AF fan from FC Keep Duct System utilizing Velocity Pressure the same

38 ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67 Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): Flow: 20,000 cfm (9.4 m3/s) Pressure: 8 in-wg (2.0 kpa) Selection Efficiency: 82% FEG: 85 Fan diameter: 44.5 BHP: 30.7 hp (22.9 kw) X SFP: 1.53 hp/kcfm FEG: 85 FAIL

39 ANSI/ASHRAE/IES Std Chapter 6 Fan System Power and Efficiency Using the values from the table A = Sum of [PD x CFM / 4131] A = 10.4 bhp (cfm x ) + A» Up to 36.4 bhp allowed

40 ASHRAE : Fan Power Limitation Proposed addition of fan efficiency requirement FEG67 Example (Single fan, VAV, Option 2 = 1.3 hp/kcfm, A=0): Flow: 20,000 cfm (9.4 m3/s) Pressure: 8 in-wg (2.0 kpa) Selection Efficiency: 82% FEG: 85 Fan diameter: 44.5 BHP: 30.7 hp (22.9 kw) SFP: 1.53 hp/kcfm FEG: 85 PASS *PER the 90.1 tables, up to 36.4 bhp allowed or 1.82 hp/kcfm

Industry Today (DOE push) 2010 - AMCA 205 Fan Efficiency Grade Focus on aerodynamic quality of fan based on peak total efficiency Just fan.

41 Industry Today (DOE push) AMCA 205 Fan Efficiency Grade Focus on aerodynamic quality of fan based on peak total efficiency Just fan ISO (FMEG (Fan/Motor efficiency Grade) * AMCA 207 Fan System Efficiency (NEW) *2018 AMCA 208 Calculation of Fan Energy Index (replaces AMCA 205) NEMA MG.1 Premium Efficiency Motor Tables AMCA 205 has been adopted in IECC-2015, ASHRAE , , IGCC 2012, IAMPO (Uniform Mechanical Code), and others. Please note that ASHRAE first starting using FAN BHP per CFM limitations on full fan systems!

42 Where are we going? übefore > Wild West ü2010 to > First Attempt to marry Fan Performance to Fan System Performance. What ultimately is consumer getting? FEG failed to represent the entire picture. Committees starting meeting in 2013 to develop next standards. ü2018 -> Second Attempt. Fan Energy Index (FEI), Fan Electrical Power (FEP) Introduction to WATTS / CFM (similar to chiller KW/TON)

43 What is the consumer paying in electricity and what is involved? AHRI 1210 AMCA 210 Remember me? 4-5% 2% 15-40% 5-9% 5-12% POWER IN VFD loss (4-5%) Motor Loss (5-12%) Belt Loss (5-9%) Bearing Loss (2-3%) Fan Aero Loss Power Out 15-40% NEMA MG.1 Input Power AMCA 203 ALL-IN!

44 AMCA Calculate Overall Fan System Efficiency (h es ) h es = h S x h B x h MC Fan - h S Belt / Transmission* - h B Motor - h M Drive *For Direct Drive system, h B = 1 Motor & Drive - h MC

AMCA 208-18 Calculation of the Fan Energy Index

45 AMCA Calculation of the Fan Energy Index Utilizing a multi-fan array Ns, ref = 59-60% Best Worst

46 AMCA Calculation of the Fan Energy Index incorrect method Example is for system with 50,000 cfm and fan static pressure of 6. FEP ref = each fan is treated as a single entity in the airstream Highest FEI has highest input power. Best Worst

47 AMCA Calculation of the Fan Energy Index Using Real Data! Fan Type Fan Size Airflow (cfm)/fan Static Pressure FEP ref /n (kw) h s actual h trans def h mtr def h vfd def FEP act (kw) FEI Watts/ CFM EPFN , % 100% 95% 96% FEG EPFN (2) , % 100% 94.1% 96% EPFN (4) 27 12, % 100% 93% 96% ACF (5) 27 10, % 100% 93% 96% EPFN (10) , % 100% % ECM Array (12) , % N/A N/A N/A EPFN (20) , % 100% 89.5% 96% h trans = 1 for direct drive system ECM fan efficiency includes motor/vfd losses. Best Worst

48 Fan Type # Fans CFM/Fan Fan RPM BHP Static Effic. Fan Comparison for Houston Area Hospital Motor Effic. Motor Size Total Effic Total BHP Total Unit kw Total Unit HP W/ CFM Annual Operating cost EPQN $139, AFLO $141, Aero-EP $147, EPQN $156, MPQN $159, FWT $188, FEG * Houston Hospital Texas Medical Center 65,000 CFM at (FUTURE) Fan Efficiency = (CFM * Pressure)/ BHP (Brake Horsepower) VFD losses not accounted for Best Worst

49 Watts/CFM for Air Handling Units (KW/TON for chillers) FEI (Fan Energy Index) is a metric to compare Fan System Options FEP (Fan Electrical Power) is the culmination of what the consumer expects to pay for electricity/utility consumption Watts/CFM is a simple metric to relate common language based on the already existing 40 year conversation regarding KW/TON on chillers Fans 38% Chiller 34% Pumps 23% Annual Energy Usage 65% of energy is moving heating/cooling around the building Tower 5%

50 Questions? Scott Sevigny, PE Shah Smith & Associates Mike Donovan HTS Texas

Fan Efficiency Grades and System Effect and Their Effects on HVAC Systems

Fan Efficiency Grades and System Effect and Their Effects on HVAC Systems Matt Spink, P.E. Greenheck Fan Corporation Learning Objectives Understanding Fan Efficiency Grades (FEG) Selection of fans within