A NEW RECIPE FOR HVAC SYSTEM

Transcription

1 A NEW RECIPE FOR HVAC SYSTEM PERFORMANCE & EFFICIENCY COOKING UP SAVINGS BY IMPROVING HVAC SYSTEM EFFICIENCY THE PANEL John Lolmaugh Director Brand Facilities Jack in the Box & Qdoba Jeremy Reefe Program Advisor, CQM Program, San Diego Gas & Electric Team Lead, Big Bold Energy Efficiency Strategies & CEESP Co Chair, Western HVAC Performance Alliance (WHPA) Executive Committee Don Langston President, Aire Rite Air Conditioning & Refrigeration, Inc. National Board Member, Air Conditioning Contractors of America (ACCA) ACCA representative to the Western HVAC Performance Alliance (WHPA) Executive Committee Chairman, WHPA Commercial HVAC Quality Maintenance Committee Vice Chairman, ASHRAE and ACCA Standard 180 Commercial HVAC Maintenance Committee A NEW RECIPE FOR HVAC SYSTEM PERFORMANCE & EFFICENCY OVERVIEW Learn how mechanical cooling efficiency can be effectively measured, diagnosed and improved using new technologies proven in recent studies. Review a recent project showing significant improvements in operating efficiency, lowered energy costs and increased comfort for customers and employees. Deploy possible solutions to reduce operating costs and increase your bottom line. Establish simple benchmarking tools to rank the efficiency of each restaurant. 1

2 HOW MUCH DOES HVAC EFFICIENCY IMPACT RESTAURANT ENERGY INTENSITY? GENERALLY ACCEPTED INDUSTRY WISDOM Impact of Improper Installation and Maintenance 30% efficiency is lost out of the Box!! Commonly noted field problems Refrigerant charge Incorrect airflow over the coil Equipment size Duct sizing Duct Leakage Out of tolerance excursions Up to 30% off of OEM design Up to 50% off of design Routinely, % too big Routinely, 50% too small Up to 50% of airflow 2

3 A TYPICAL ROOFTOP PACKAGE UNIT Evaporator Coil Supply Air Fan Condenser Fan Condenser Coil Compressor Heat Exchanger Return Air Supply Air IEA ANNEX 36 Report Poor HVAC Installations Undermine Efficiency Programs and Cost All Parties $$$ An international group studied the impact of quality installation (QI) and quality maintenance (QM) of HVAC systems. This collaboration was based on applying the HVAC industry standards for installation and maintenance This study quantified impacts on system performance (e.g., capacity, energy utilization, etc.) related to varying QI and QM practices / attributes for varied equipment applications. From generally accepted wisdom to tested / documented & factual knowledge. IEA ANNEX 36 QI / QM SENSITIVITY STUDIES (Single Fault Effects to System Performance) Avoiding Efficiency Degradation due to Poor Installations and Maintenance Duct leakage The most influential fault on performance Impact: 10-30% energy penalty on annual energy consumption Refrigerant charge The 2 nd most influential fault 30% undercharge: 20% energy penalty 30 % overcharge: 10 to 15% energy penalty 10% undercharge: 2 to 3% energy penalty. Undersized cooling TXV pronounced in localities with a high number of cooling mode operating hours 14 % more energy used in Houston (40 % undersize) 3 % energy penalty in Chicago. 3

4 TYPICAL HVAC AIR DISTRIBUTION FAULTS Excessive air filter restriction Excessive outside air or economizer airflow High static pressure from undersized, poorly installed and/or restrictive duct systems Improper register airflow Inadequate indoor fan airflow Roof curb leakage and/or air bypass Excessive duct losses through air leakage around connections, along with inadequate insulation Slide 8 THE HVAC COMPRESSOR IS THE HEART OF THE SYSTEM AND CONSUMES APPROXIMATELY 80% OF THE POWER TYPICAL HVAC REFRIGERATION FAULTS Dirty and plugged evaporator coils Inadequate equipment airflow Damaged and/or leaking evaporator coils Dirty and plugged condenser coils Improperly charged refrigerant circuit Inefficient Compressors Contaminants in refrigerant Slide 8 4

5 TYPICAL HVAC ELECTRO MECHANICAL FAULTS Economizer Sensors inoperable Economizer linkage and drive damaged or not adjusted Operators adjust or reprogram thermostats Refrigerant controls bypassed or failing Electrical components and controls become worn and fail Control system become non functional or fall out of calibration Slide 8 RESTAURANT AIR BALANCE The volume of airflow in a commercial kitchen exhaust system may be up to 20 times greater that the airflow in a dining room. However it is: Invisible and can be difficult to measure Extremely expensive Usually out of control Often uncomfortable Affects the quality of food Impacts health safety Impacts employee productivity THE DELIVERY METHOD OF MAKE UP AIR INTO THE KITCHEN IS CRITICAL TO MAINTAINING A SUCCESSFUL AIR BALANCE 5

6 WHEN A KITCHEN EXHAUST SYSTEM IS OUT OF BALANCE By understanding how these elements can be controlled and managed, you can gain control of these unseen costs in your buildings. For every 1 cfm of negative air balance over the course of a year it will cost $ 1.00/cfm based on 10 kwh. A 3000 cfm negative air condition would cost $ 3,000! SIMPLE BENCHMARKING AS A TOOL Gather the data of average square feet in each restaurant Gather the electric usage for each site over the past 18 to 24 months Gather the total dollar costs per site over the past 18 to 24 months Use the appropriate benchmark of the Energy Intensity kwh/sf/yr. or $/Sf/Yr. as comparison tool. Rank the sites from highest to lowest electrical users and determine the next steps in investigating the causes of the highest electric consuming restaurants JOHN LOLMAUGH JACK IN THE BOX DIRECTOR BRAND FACILITIES We in the restaurant Industry are consistently being approached from many different directions on energy savings products and solutions. We found this EEO project to provide an approach that can deliver results on several levels: Energy efficiency/savings Guest and employee comfort enhancements Learning s and applying best practices to New Construction, Projects and Facilities Management 6

7 Jack In The Box is committed to improving the operating energy efficiency of their national portfolio of restaurants. An energy intensity audit was conducted of a group of 74 Southern California restaurants to benchmark and compare energy cost per square foot. The restaurants were ranked from the lowest to highest energy users. The 9 highest energy using restaurants were selected for a comprehensive HVAC (EEO) Equipment Efficiency & Optimization project. PROJECT SCOPE Perform building air balance and air flow measurements and operational efficiency of kitchen exhaust fans and make up air fans. Perform necessary modifications to kitchen cooking hoods to maximize overall ventilation efficiency. Retro commission each the HVAC systems using software and tools to compare efficiency improvements pre and post. Installation of new thermostats and a complete refurbishment and upgrades to all rooftop unit s equipped with economizers. Review the project results upon completion. JOHN LOLMAUGH JACK IN THE BOX DIRECTOR BRAND FACILITIES JOHN LOLMAUGH JACK IN THE BOX DIRECTOR BRAND FACILITIES What you need to know before starting a project such as this: Know your data (where is your energy $ being spent) Understand your current preventative maintenance and repair programs Understand that this is not the end of the project once the initial work is completed When performed correctly additional opportunities will usually be identified Continue to monitor data to ensure what level of savings is applied to your Brand HVAC REFRIGERATION DIAGNOSTIC &SERVICE TOOL RESULTS 7

8 SUMMARY RESULTS REFRIGERATION DIAGNOSTIC & SERVICE TOOL A total of 9 restaurants were included in the project with 25 rooftop package HVAC units, totaling tons of cooling capacity. The average age of the rooftop package units was 8 years (2006). The oldest is 1999 and the newest ones are Of the 38 circuits tested in, only the 4 newest ones met the factory baseline performance levels. The energy efficiency gains achieved using the very conservative California Energy Commission energy saving value of kwh will be $ 12,066 annually. This does not take in other factors such as improved reliability and increased equipment life. ADVANCED INTERGRATED DIGITAL ECONOMIZER UPGRADES WERE COMPLETED TO 19 ROOFTOP HVAC PACKAGE UNIT Upgraded to the latest generation of advanced digital economizer controls, sensors and new damper motors Refurbish the economizer return air and outside air dampers and linkage Measure and adjust minimum and maximum airflows to maintain building air balance and commission the economizer controls Upgraded economizers will typically eliminate approximately hours of compressor runtime annually in the local Southern California climate zones, saving $ 2,100 to $ 3,150 per unit EQUIPMENT EFFICIENCY & OPTIMIZATION PROJECT SUMMARY PART 1 Site # Unit Equipment Efficiency Pre Equipment Efficiency Post Equipment Delivered Delivered System Overall CFM Improvement Efficiency Pre Efficiency Post Improvement Balance Pre Overall CFM Balance Post 1 AC1 71% 94% 23% 63% 88% 25% AC2 76% 95% 19% 58% 92% 34% 2 AC1 60% 93% 33% 51% 86% 35% AC2 87% 95% 8% 65% 89% 24% AC3 80% 91% 11% 60% 91% 31% AC4 76% 93% 17% 56% 84% 28% AC5 68% 84% 16% 89% 95% 6% 3 AC1 73% 92% 19% 54% 90% 36% AC2 94% 99% 5% 72% 88% 16% 4 AC1 81% 92% 11% 63% 83% 30% AC2 78% 92% 14% 53% 79% 26% AC3 69% 81% 12% 49% 71% 22% 8

9 EQUIPMENT EFFICIENCY & OPTIMIZATION PROJECT SUMMARY PART 2 Site # Unit Equipment Efficiency Pre Equipment Efficiency Post Equipment Improvement Delivered Delivered Efficiency Pre Efficiency Post System Improvement Overall CFM Balance Pre Overall CFM Balance Post 4 AC1 81% 92% 11% 63% 83% 20% AC2 78% 92% 14% 53% 79% 26% AC3 69% 81% 12% 49% 71% 22% 5 AC1 78% 98% 20% 51% 93% 42% AC2 74% 92% 18% 72% 91% 19% 6 AC1 72% 83% 11% 59% 61% 2% AC2 56% 80% 24% 71% 65% 6% 7 AC1 72% 92% 20% 38% 81% 43% AC2 65% 90% 25% 62% 70% 8% 8 AC1 60% 91% 31% 52% 78% 26% AC2 68% 102% 34% 57% 75% 18% 9 AC1 75% 76% 1% 51% 78% 27% AC2 85% 97% 12% 45% 95% 50% LESSONS LEARNED & OTHER COMMON PROBLEMS The return air ducts being undersized, restricting air flow to the unit Damaged supply and return air ducts from various service trades who run cabling and other equipment such as soda lines above the ceiling space Restricted supply and return air grilles caused by dirt, paint, etc Air leakage abound the curb adapters and inside the curbs resulting in air bypassing between the supply and return air Overall building negative air pressure condition resulting in reduced cooling efficiency and increased equipment run time JEREMY REEFE SAN DIEGO GAS & ELECTRIC PROGRAM ADVISOR II, ENERGY EFFICIENCY CALIFORNIA S ENERGY EFFICIENCY STRATEGIC PLAN HVAC SECTOR VISION Residential and small commercial HVAC will be transformed to ensure that technology, equipment, installation, and maintenance are of the highest quality to promote energy efficiency and peak load reduction in California s climate. From California Public Utilities Commission (CPUC) Decision which orders four Big Bold Energy Efficiency Strategies for the purpose of spurring market transformation. Unitary HVAC is among them. A GOAL FOR HVAC: New climate appropriate HVAC technologies (equipment and controls, including system diagnostics) are developed with accelerated market penetration. At least 15 percent of equipment shipments are optimized for California s climate by 2015 and 70 percent by STRATEGY FOR ACHIEVING HVAC GOALS An HVAC Advisory Group [the Western HVAC Performance Alliance AKA: WHPA] should be chartered to involve high level HVAC industry stakeholders such as manufacturers, distributors, and contractors to coordinate industry sponsorship of and participation in HVAC strategies. Membership should also include other key players, such as the CPUC, Energy Commission, utilities, local building officials, building owners/managers, consumers, and the Federal government. From California Energy Efficiency Strategic Plan (CEESP) 27 9

10 CALIFORNIA S INVESTOR OWNED UTILITES OFFER INCENTIVES TO HELP RESTAURANTS BECOME MORE ENERGY EFFICIENT! WHAT IS THE PREMIUM EFFICIENCY COOLING PROGRAM? Quality Installation 1) Premium Tune ups Contractors deliver comprehensive one time HVAC services 2) Quality Maintenance (QM) Customers eligible for incentives for 3 year Maintenance Plans 3) Quality Installation (QI) Contractor and/or customer incentives for installation to ANSI/ACCA industry standard THE ADVANCED RTU CAMPAIGN 10

11 REFERENCE MATERIAL ADDITIONAL REFERENCES HVAC SYSTEM LONG TERM SUSTAINABLITY STRATEGY Test in Measurement Electrical Systems System Air Flow System Pressures System Temperatures Compare Results Manufacturers Specification Measured Data Determine out ofspec conditions Determine Test in Operating Efficiency Diagnose Problem Areas Troubleshoot causes Determine solutions Cost verses Benefits Make Repairs Adjustments Component Replacements Mechanical Repairs Possible Replacement Options Test out Measurement Verify results Determine Testout Operating Efficiency Calculate performance improvement Standard 180 Based Maintenance Performance Objective Goals Inspection & Maintenance Tasks Inspections & Task Frequency Condition Indicators 11

12 Utilities consume approximately 2.5 to 3.4 percent of total restaurant sales, depending on the type of operation (source: National Restaurant Association Restaurant Industry Operations Report). While this seems like a relatively low expenditure, energy efficiency is a very cost effective measure to increase profitability. A $1 reduction in energy costs equals $12.50 in sales at an 8% profit margin. Any profit margin less than 8% will only have a greater impact. There is reduced pressure to increase sales, turnover tables quicker with implementation of HVAC system performance and efficiency projects. Source: Sustainable Food Service MAKE A POSITIVE FINANICAL IMPACT TO YOUR TOP LINE &BOTTON LINES QUESTIONS? 12