HVAC Air Filtration Overview and Life Cycle Cost Case Study Garry Pangborn March 8, 2012

1. HVAC Air Filtration Overview and Life Cycle Cost Case Study Garry Pangborn March 8, 2012 Freudenberg Filtration Technologies

2. The Air We Breath - Sizes of Common Particles

3. The Air We Breathe - Particle Size Distribution of Atmospheric Air • The activities of modern society have greatly increased presence of sub-micron particles Primarily Naturally-Occurring Primarily Man-made Fine

4. The Air We Breathe – Health & Wellness Considerations • Every day, the typical adult in the U.S.: • Eats 3 lbs of food • Drinks 4 lbs of fluids • Breathes 35 lbs of air! • Particles are deposited into respiratory tract; the smaller the particle, the deeper it can reach • EPA estimates that people spend 90% of time indoors • Sick Building Syndrome, Building Related Illness, Pandemics • Productivity benefits of improved IAQ (Indoor Air Quality) • Increases in allergy and asthma cases nationwide • Increasing evidence that disease can spread via airborne routes (droplet nuclei)

5. The Air We Breathe – Dust Concentrations • What is the dust concentration in this room? • 10 to 50 μg/m3 • What is it in the extremes in the world? • Lowest recorded – Antarctica at 0.00001 μg/m3 • Highest recorded – Sandstorms at 4,000 to 6,000 μg/m3 • What is Urban Typical? • In the United States – 20 to 50 μg/m3 • In China – 300 to 500 μg/m3

6. Air Filtration Mechanisms Electrostatic Attraction Inertial Impaction (-) (+) Filter Fiber Brownian Diffusion Interception

7. Filter Efficiency - Filtration Mechanisms Working Together • Filter Efficiency is the combination of the various capture schemes • Sieving • Inertial impaction • Interception • Diffusion • Electrostatic attraction

8. Filtration Efficiency - What is MERV? Minimum Efficiency Reporting Value (MERV) • ASHRAE 52.2 standard • Classification system for filters based upon particle capture efficiency • Numerical designation between 1 and 16 ASHRAE 52.2 MERV Table LEED Point for MERV Level ≥13

9. Filter Pressure Drop and Energy • Energy consumption impact: Up to 30% of fan energy usage due to filter pressure drop Governing equation for how lower ΔP equates to lower energy usage: Q x ΔP x t Energy = η where… Q = volumetric flow rate ΔP = pressure drop t = time η = motor-fan efficiency Target operating zone.

10. Filter Pressure Drop and Energy Optimum Filter Change-out Timing Goal should be to change-out filters at the lowest point on this curve.

11. Filter Selection Criteria • Life cycle costs most important • Note difference in values between LCC and Initial Cost • Avoidance of catastrophic failures due to blowout or moisture are noteworthy • Fit and MERV naturally a key criteria • Vendor knowledge / service is valued

12. Filter Types by Efficiency Levels

13. A Case Study in Energy and Life Cycle Cost Savings Case Study Background • Interest in energy savings and sustainability • Business and Aerospace Building, 3rd Floor • Pursued side-by-side energy consumption comparison study Business & Aerospace Bldg Single-stage 2-Stage System vs. Filter Installation • Side access housing • 4 rows of 20” tall tracks • 5 columns of filters 24” wide • Side-load gasketing • Two stages • 2” pleated pre-filter • 20”x24”x12” box filter • Single stage – no pre-filter • 20”x24”x20” pocket filter • 4 pockets per filter

14. A Case Study in Energy and Life Cycle Cost Savings Head-to-Head Pressure Drop Across Filter Banks Data courtesy MTSU

15. A Case Study in Energy and Life Cycle Cost Savings Illustration of Pressure Drop Comparison Across Filter Banks

16. A Case Study in Energy and Life Cycle Cost Savings Energy Monitoring • ABB variable frequency drives (VFD) • 30 HP motors • Hourly data logging of motor voltage and current for each air handler • Power data then tabulated in Excel Data Example (courtesy MTSU)

17. A Case Study in Energy and Life Cycle Cost Savings Energy Monitoring Results Data courtesy MTSU

18. A Case Study in Energy and Life Cycle Cost Savings Filter Pressure Drop Checks under Controlled Laboratory Conditions

19. Sustainability Impact – In Addition to Energy Reduction • Potential waste reduction on campus • Major reduction in filter usage • Pre-filters eliminated • 3x lifetime of typical box/cell filters Filter Qty: 300  20 93% potential reduction in usage over 3 yr period

20. Filtration Life Cycle Cost Reduction • Note importance of energy consumption • For every 0.1” w.g. reduction in P there is an energy savings of $17 per filter per year (@ $0.06 per kWh) Initial Filter Costs Operating Costs • Case Study Total Cost of Ownership Impact (over 3 years) • Energy Cost 44% • Filter Cost 54% • Labor Cost 86% • Overall 50%

21. Additional University Case Studies Additional Example #1 Southeast Additional Example #2 - Midwest Additional Example #3 Northeast • V-bank Type Filter (no pre-filter) • Filter dP at 30 months of service: 0.68” w.c. (new 0.28” w.c.) • Case study presented at 2010 MIAPPA summer conference: www.fm.wmich.edu/miappa/conf/s10/index.html • Pocket Filter (no pre-filter) • Filter dP after 24 months of service: 0.24” w.c. (new = 0.20” w.c.) • Pocket Filter (no pre-filter) • Filter dP after 40 months of service: 0.29” w.c. Previous Incumbent: Pre-filters: changed quarterly Final filters: changed every 12-18 months Previous Incumbent: Pre-filters: changed quarterly Final filters: changed annually Previous Incumbent: Pre-filters: changed quarterly Final filters: changed every 12-18 months

22. Greenguard Certification Check air filters for certification • 3rd party qualification • Assesses emissions of VOC’s (i.e. formaldehyde) • Evaluates product for mold/fungi growth Greenguard Certificate of Compliance

23. Trends in Air Filtration Market • Elimination of roll filters • Consolidation of 2-stage pleated filter + box filter to long-life pocket technology or V-bank filters • Higher efficiencies (LEED - MERV 13) • End-user focus on energy conservation (lower dP filters) • End-user focus on life cycle costs • End-user focus on sustainability and less waste • Growth of synthetic media filters vs. glass due to: • Lower cost • Moisture resistance • Lower VOC emissions • Ultraviolet (UV) lights used in conjunction with air filters to help keep heat transfer coils ultra clean • Nanofiber filter media • Glass fiber shedding • More puncture resistant • Installer friendly (skin contact)