Demand Control Ventilation What, When and Where?

Transcription

1 Demand Control Ventilation What, When and Where? Presented by: Todd Bell Sr. Energy Analyst Fisher-Nickel Inc. Rich Swierczyna Sr. Engineer Fisher-Nickel Inc. The Food Service Technology Center (FSTC) program is funded by California utility customers through the public purpose program and administered by the Pacific Gas and Electric Company under the auspices of the California Public Utilities Commission. Fisher Nickel Inc. has managed the FSTC for PG&E since Our Mission: Promote Energy Efficiency in Commercial Food Service

2 Upcoming FSTC Seminars Submetering 101 Field Guide for Finding Big Ticket Energy Waste December 16 th Fast Five Fundamentals Energy & Water Best Practices for the Beginner January 21 st 2016 Foodservice Forecast Featuring Special Guest Speaker Robin Ashton (FER) February 9 th Register online at fishnick.com Demand Control Ventilation Rebate! $700 / Exhaust Fan HP

3 Fishnick.com

4 Fundamentals of Commercial Kitchen Ventilation Package Air Handler Dedicated Kitchen Make up Air Unit Exhaust Fan 3000 cfm 6000 cfm 3000 cfm Exhaust air volume is expressed in Cubic Feet/Minute (CFM) 1 cfm = 1 cubic foot per minute 1 cubic foot is about the size of a basketball The hood eats a lot of basketballs!

5 Common Exhaust Hood Styles Wall Mounted Canopy Single Island Canopy Double Island Canopy Back Shelf Pass Over The Problem: Typical Hotel Kitchen at 3:00 PM No appliance use but exhaust at 100%! Front Line Back Line

6 Solution: Demand Ventilation Control Technologies Duct Temperature Sensor & Infrared Sensors Duct Temperature Sensor & Vapor Detection Duct Temperature Sensor DCKV System Energy Use Profiles 16 Exhaust and Makeup Air Fan Power 16 Exhaust and Makeup Air Fan Power Power (kw) Avg. without DVC = 12.7 kw 8 6 Power (kw) Avg. without DVC = 14.0 kw Avg. with DVC = 5.8 kw Time Avg. with DVC = 5.3 kw Time Clarke Kerr Dining Commons Mark Hopkins Hotel

7 Retrofitting Demand Controlled Kitchen Ventilation (DCKV) Does it Make Sense? START (1) Do you know about DCKV hood control and its energy saving potential? Refer to industry literature on DCKV (6) Do the exhaust hoods fail to capture & contain cooking heat & smoke? Undertake a hood tuneup or upgrade to improve capture (2) Do you have more than 12 (linear) feet of exhaust hood (typically more than 3000 cfm)? (5) Are there times during the day when appliances are not actively cooking food while the hood is operating? (3) Are the exhaust hoods in your kitchen a backshelf or proximity sytle (versus canopy style) Backshelf hoods are generally more efficient and typically operate at lower airflow.. ROI caution (4) Do you operate your exhaust hoods less than 8 hrs per day? (7) Do you have single island hoods over heavy duty equipment? (8) Do you have multiple exhaust hoods connected to one exhaust fan? (9) Do you have a large underfired broiler (charbroiler) on your cookline? DCKV caution. Caution. Charbroiler exhaust reduction is limited (12) Is the noise from the exhaust hood excessive? (11) Do you cool your makeup air? (10) Do you heat your makeup air? Noise reduction not ROI caution justification for DCKV (13) Are the utility rates in your area considered high? (ex. $.06/kWh is low, $.15/kWh is high) Gas rates over $1.00/therm are considered high) (14) Do you know the total exhaust air flow rate (in cfm) for your exhaust hoods? Do you know your nameplate horsepower of the exhaust and makeup fans? Engage an energy professional YOU ARE LIKELY TO GET GOOD ROI ON A DCKV SYSTEM END

8 Is a Demand Controlled Kitchen Ventilation (DCKV) START (1) Do you know about DCKV hood control (variable speed exhaust) and its energy saving potential? Refer to industry literature on DCKV Check out the Food Service Technology Center s DCKV Webpage: Is a Demand Controlled Kitchen Ventilation (DCKV) (2) Do you have more than 12 (linear) feet of exhaust hood (typically more than 3000 cfm)?

9 Is a Demand Controlled Kitchen Ventilation (DCKV) (3) Are the exhaust hoods in your kitchen a backshelf or proximity style (versus canopy style)? Backshelf hoods are generally more efficient and typically operate at lower airflow Note: Several leading QSR chains are rolling out DCKV systems that communicate directly with the cooking appliances, making the ROI more attractive. Is a Demand Controlled Kitchen Ventilation (DCKV) (4) Do you operate your exhaust hoods less than 8 hrs per day?

10 Is a Demand Controlled Kitchen Ventilation (DCKV) (5) Are there times during the day when appliances are not actively cooking food while the hood is operating? Is a Demand Controlled Kitchen Ventilation (DCKV) (6) Do the exhaust hoods fail to capture & contain cooking heat & smoke? Caution: Undertake a hood tune up or upgrade to improve capture Note: An exhaust hood that is not working satisfactorily at full speed is not going to work well at reduced speed.

11 Is a Demand Controlled Kitchen Ventilation (DCKV) (7) Do you have single island hoods over heavy duty equipment? DCKV Caution! Note: Single island hoods are notorious for not capturing and containing smoke produced by heavy duty cooking equipment. They may perform even worse when the DCKV system reduces the exhaust airflow. Is a Demand Controlled Kitchen Ventilation (DCKV) (8) Do you have multiple exhaust hoods connected to one exhaust fan? Note: It is difficult to reduce the exhaust airflow from multiple hoods serving different production roles when connected to one exhaust fan. For example, if cooking is going on under one hood, then all hoods need to be operating at full speed. Exception: When the DCKV system incorporates code approved dampers to modulate air flow to the individual hoods.

12 Is a Demand Controlled Kitchen Ventilation (DCKV) (9) Do you have a large under fired broiler (charbroiler) on your cookline? Note: A charbroiler needs almost as much exhaust airflow in a ready to cook mode of operation as it does when cooking meat products. Thus the reduction in exhaust air may be limited and the ROI challenged. However, if a charbroiler part of a much larger cookline, this issue may be less significant. Is a Demand Controlled Kitchen Ventilation (DCKV) (10) Do you heat your makeup air? Note: Makeup air heating savings with DCKV can be significant, supporting the ROI.

13 Is a Demand Controlled Kitchen Ventilation (DCKV) (11) Do you cool your makeup air? Note: The energy required to cool makeup air in many areas of the country is not significant and does not impact ROI. Is a Demand Controlled Kitchen Ventilation (DCKV) (12) Is the noise from the exhaust hood excessive? Noise reduction not justification for DCKV

14 Is a Demand Controlled Kitchen Ventilation (DCKV) (13) Are the utility rates in your area considered high? (eg. $.06/kWh is low, $.15/kWh is high) Gas rates over $1.00/therm are considered high) Is a Demand Controlled Kitchen Ventilation (DCKV) (14) Do you know the total exhaust air flow rate (in cfm) for your exhaust hoods? Do you know your nameplate horsepower of the exhaust and makeup fans? Engage an energy professional

15 Is a Demand Controlled Kitchen Ventilation (DCKV) YOU ARE LIKELY TO GET GOOD ROI ON A DCKV SYSTEM Secure quote(s) from DCKV supplier/installer 16 Exhaust and Makeup Air Fan Power 14 Example of Savings: Mark Hopkins Hotel Power (kw) Avg. without DVC = 14.0 kw Design Exhaust Ventilation Rate (cfm) 22,500 Average Fan Power Reduction (kw) 8.70 Total Exhaust Fan (HP) 15.0 Yearly Fan Energy Cost Savings ($) 12,064 Yearly Heating and Cooling Energy Cost Savings ($) 9,460 Total Yearly Operating Cost Savings ($) 21,524 DVC System Installed Cost ($) 15,000 PG&E Rebate ($) 10, Avg. with Time DVC = 5.3 kw Pay Back Period (yrs) 0.2 Calculated using $0.14/kWh, $1.00/therm, operating 365 days per year.

16 Example of Savings: Savings: U.C. Berkeley Clark Kerr Campus Avg. without DVC = kw Power (kw) Exhaust and Makeup Air Fan Power Avg. with DVC = 5.8 kw Time Design Exhaust Ventilation Rate (cfm) 12,200 Average Fan Power Reduction (kw) 6.98 Total Exhaust Fan (HP) 8.0 Yearly Fan Energy Cost Savings ($) 4,990 Yearly Heating and Cooling Energy Cost Savings ($) 2,350 Total Yearly Operating Cost Savings ($) 7,340 DVC System Installed Cost ($) 16,000 PG&E Rebate ($) 5,600 Pay Back Period (yrs) 1.4 Calculated using $0.14/kWh, $1.00/therm, operating 365 days per year. DCKV Recap the Ideal Candidate Long Exhaust Hood(s) (12 ft or more) = More cfm = More HP = More Rebate $ Dedicated fans for individual hoods Long Operating Hours ( 8+ hours/day) Long appliance idle periods Light to Medium duty appliances = Ovens, Steamers, Fryers & Griddles Minimal Charbroiling

17 Target Customers Hotels Hospitals University Cafeterias Corporate Campus Cafes Large Full Service Restaurants Super Markets Cautions Exhaust System must be working effectively as single speed before Considering DCKV Proper commissioning is key Existing Three Phase fan motors for compatibility with variable frequency drives

18 Todd Bell Sr. Energy Analyst Fisher-Nickel Inc Rich Swierczyna Sr. Engineer Fisher-Nickel Inc