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					       CA Title 24 Requirements for
       Supermarket Refrigeration

                                                        VaCom Technologies
                                                     Heschong Mahone Group

                                                                             Sept. 22, 2010


09/22/2010   CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes
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Introduction
● California Energy Commission (CEC) and California
  Air Resources Board (CARB) are working together
  on the next round of the state’s building energy
  efficiency code (2011 Title 24)
● This is the first time that Title 24 is dealing with
  direct GHG emissions
● CARB team (ICF International) is addressing
  emissions (direct and indirect) and leak reduction
● For CEC, IOU team (HMG/VaCom) is addressing
  energy savings – the focus of this meeting



            CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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IOU Support for 2011 Title 24
● The California Investor Owned Utilities (IOUs) are
  actively supporting the California Energy
  Commission (CEC) in developing the state’s
  building energy efficiency code (Title 24)
● Their joint intent is to achieve significant energy
  savings through the development of
  reasonable, responsible, and cost-effective code
  change proposals for the 2011 code update and
  beyond
● As part of the IOU effort, at the request of the CEC,
  we are hosting stakeholder meetings to get
  industry input and feedback on our code change
  proposals

           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Code Change Activity
● 2011 T-24 Base Code (Part 6 of Title 24)

● 2011 Reach Standard (Part 11 of Title 24)
   ● Green Building Standard – i.e. CalGreen

   ● Two levels of efficiency:
     ●   Tier I              15% beyond the Base Code
     ●   Tier II             30% beyond the Base Code

● Future Codes
   ● 2014 T-24

   ● Future Reach Standards



              CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Requirements for a Successful Base Code
● To be included in the base code, a measure must:
  ●   Be cost-effective
       ●   based on the standards-induced additional first cost,
           maintenance costs, measure life, and energy cost
           savings
       ●   typically according to the CEC Time Dependent
           Valuation (TDV) life-cycle costing methodology and
           weather data
  ●   Be possible to implement using equipment that
      is available from multiple providers or that is
      reasonably expected to be available following
      the code change



               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Purpose of Reach Code
● Easily adopted, standardized approach for
  jurisdictions wishing to implement a more stringent
  code than Title 24
● Basis for awarding incentives for utilities or other
  entities seeking to promote more efficient building
  techniques
● Present a framework to introduce and test energy
  efficiency measures that are not yet ready for
  adoption in the Base Code




           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Stakeholder Meetings Process
● Minimum of three meetings:
  ●   First: present scope, request data
       ●   Code change direction and possible options
       ●   Methodology
       ●   Best practices, market data
  ●   Second: present findings
       ●   Results of energy analysis
       ●   Preliminary cost effectiveness
  ●   Third/final: present proposed code language
● All meetings can be attended remotely




               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Submitting Comments
● Informal Comment Process
● Comments can be submitted to CASE authors,
  substantive comments will receive responses
● The team will work with stakeholders to resolve
  issues as best we can
● Questions and responses will not be posted online,
  but common or frequent questions will be
  communicated as necessary between stakeholders
● The CEC has a formal comment process during
  later stages of the official rulemaking process


           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Types of Code Change
● Mandatory Measure:
  ● Mandatory measures must be satisfied whether
    the prescriptive or performance method is used
    to show compliance
● Prescriptive Requirement:
   ● When there is not a performance compliance
     (computer modeling), prescriptive requirements
     are essentially mandatory requirements




          CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Types of Code Change –                                               Ctd.

● Performance Requirement:
   ● Computer modeling
   ● Prescriptive requirements are used to define a
     standard design to set the energy budget
   ● No performance option is being proposed




           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Schedule: Key Dates
● Mar 2010 - Dec 2010
  ●   CEC develop foundation /methodology
  ●   IOUs:
       ●   Conduct research, and cost effectiveness analysis
       ●   Present results at stakeholder meetings
● Jan 2011
  ●   IOUs finalize code change proposals for submittal to CEC
● Feb 2011
  ●   CEC opens Rulemaking for Title 24, develop 45-day
      language
● June 15, 2011
  ●   Title 24 Adoption date
● Jan. 1, 2013
  ●   Title 24 Implementation date
               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Meeting Protocols
● Please DO NOT place your phone on HOLD
● Please mute your microphone, unless you want to
  speak
● Ask questions/comment by “chat” or by voice
● We want to hear your concerns
   ●   Opposing viewpoints are encouraged
   ●   We are seeking information, not resolution
● Time is limited
   ●   Raise your hand and be acknowledged by presenter
   ●   Clearly state your name and affiliation prior to speaking
   ●   Speak loudly for the people on the phone
● Minutes and presentation material will be available
  online – we will distribute link


               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Base Code Measures
● Floating head pressure
   ●   Floating head pressure control with variable speed fan
       control, variable setpoint logic
● Remote condenser specific efficiency
   ●   Maximum condenser fan power per unit of capacity; air-
       cooled and evap-cooled
● Floating suction pressure
   ●   Setpoint control strategy




              CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Base Code Measures (contd)
● Mechanical subcooling
   ●   Low temp subcooling from medium temp system or
       economizer on LT scrolls, screws
● Evaporator coil specific efficiency
   ●   Maximum evaporator fan power per unit of cooling
       capacity: freezer, cooler; low-profile, medium-profile
● Evaporator coil variable speed control
   ●   Primary temperature control (central systems); off-cycle
       reduced speed (single systems)




              CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Base Code Measures (contd)
● Liquid-suction heat exchangers
   ●   Display cases
   ●   Walk-in evaporator coils
● Display case LED lights
   ●   Reach-in glass door cases
● Display case lighting control




              CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Store and System Types
      Store and Refrigeration System Combinations
                              Air-Cooled               Central
                              Condenser              Distributed
          Small
                             Evap-Cooled
       Supermarket                                     Central
                              Condenser
        10,000 SF
                                                       Central
                             Fluid Cooler
                                                     Distributed
                              Air-Cooled               Central
                              Condenser              Distributed
          Large
                             Evap-Cooled
       Supermarket                                     Central
                              Condenser
        60,000 SF
                                                       Central
                             Fluid Cooler
                                                     Distributed
                              Air-Cooled               Central
                              Condenser              Distributed
         Big Box
                             Evap-Cooled
        Food Store                                     Central
                              Condenser
        150,000 SF
                                                       Central
                             Fluid Cooler
                                                     Distributed

      CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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GHG Emissions
● Low Charge Systems
  ●   Secondary loop & distributed systems modeled

● Direct GHG Emissions
  ●   Offline analysis based on annual refrigerant losses & GWP-weighting
  ●   MTCO2e results will be considered with energy analysis

● Leak Reduction Measures
  ●   Mandatory measures developed with industry input; reflect basic good
      practices without imposing cost burden




               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Direct Emissions Assumptions
 Base Case System                                                                           Secondary
                                        Centralized               Distributed
 Configuration                                                                                Loop
                                                                                             R-404A &
 Refrigerant Type                      R-404A, R-507             R-404A, R-507
                                                                                            glycol/ CO2
 Charge Size (lbs)*
   Small Supermarket
                                              610                       490                        135
   (210,420 BTU)
   Large Supermarket
                                             2,075                     1,660                       460
   (713,750 BTU)
   Big Box Food Store
                                             3,200                     2,560                       710
   (1,100,042 BTU)
 Leak Rate (percent of charge per year)
   Average                                    18%                       15%                        10%
   Range (of averages)                    15% - 25%                 10% - 15%                    5% - 15%
*Charge calculated for each refrigeration system type based on average pounds per BTU;
estimated primarily based on available literature with consideration given to supermarket data,
supermarket drawings, and manufacturer/user input.

                      CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes           09/22/2010
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Direct Emissions

 ● EE measures that impact charge size:
                                                     Change in Charge Size
  Energy Efficiency Measure*                          Relative to Baseline

  Floating head pressure control                               Increase
  Heat reclaim                                                 Increase
  Remote condenser specific efficiency                         Increase
  *Measures not listed are not assumed to impact charge size


 ● Impact of specific measures on charge size
    will be quantified based on input from
    equipment manufacturers and installers
                                                                             09/22/2010
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Analysis Methods
● DOE 2.2R whole building hourly simulation
● Fixtures loads disaggregated, balance space
  interactions (fixture, HVAC, building, etc.)
● Mass-flow/component based refrigeration system
  modeling, explicit control strategies
● Modeling of building envelope, HVAC, lighting,
  skylights, etc.




           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Base Case Assumptions
● Title 24 compliant building
   ●   Insulation, lighting power density, HVAC systems
   ●   Minimum skylights and light level control
● Display cases
   ●   T-8 lights, EC motors, low watt glass door heaters
● Walk-ins
   ●   Federal Walk-in standard compliant
● Refrigeration systems
   ●   Partial floating head pressure, fixed suction, no subcooling
● Schedules: operations, occupancy, lighting, etc.
● Project information: www.calcodesgroup.com
              CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Base Case – Large Supermarket
                                                            Sacramento weather
                                                                60,000 SF
                                                                 Air-cooled
                                                                  24 hour
                                                                                               Annual kWh
                     Display
                     Cases
                                                                 Lights                       702,657    37%
                                                                 Misc Loads                   168,641     9%
                                                   Lights        HVAC                         248,755    13%
            Compressors                                          Condensers                    76,230     4%
                                                                 Walk In Fans                  30,335     2%
                                                                 Compressors                  423,398    22%
                                                                 Display Cases                239,203    13%
                                                                           Total:           1,889,219   100%
  Walk In                             Misc Loads
   Fans
                          HVAC
                                                                 Refrigeration                 769,166 41%
Condensers




                          CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes      09/22/2010
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Cost Effectiveness
● Title 24 cost-effectiveness analysis
  ●   Time dependent valuation method
  ●   Life-cycle cost consideration including energy,
      maintenance and measure life
  ●   Statewide evaluation in multiple climate zones

● Preliminary economics (this presentation)
  ●   Single climate zone (Sacramento)
  ●   Large supermarket simulation model
  ●   Simple savings valuation ($.12/kWh)
  ●   Estimated maintenance
  ●   Simple payback

             CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Floating Head Pressure
●   Condenser controls to allow head pressure to float with ambient
    conditions to a minimum SCT of 70 F or lower, using ambient-
    following (TD) setpoint control and variable speed control of all fans
    in unison. Results for large supermarket, air-cooled condensers:
                Savings (kWh)                                   54,157
                  Savings ($)                                   $6,499
              Measure Cost ($)                                 $13,600
             Maintenance Cost ($)                               $1,600
              Simple Payback                                     2.8
●   Savings adjustment of 30% to allow for typical sensor error and
    control system variations vs. hourly simulation results.
●   Annual maintenance cost allows for cost of setpoint verification
    and/or periodic recommissioning of controls.



                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Floating Head Pressure
● Variable speed may be accomplished using a variable speed
  drive or EC condenser fan motors with variable speed control
  signal.
● Applies to air-cooled, evap-cooled and fluid coolers.
● Savings are subject to setpoint increase or override, but many
  chains have demonstrated ability to maintain setpoints over
  time.
● Code exceptions:
   ●   Allow fixed setpoint on evap-cooled condensers due to low reliability of
       RH sensors?
   ●   Allow for strategies that are equal or better than ambient-following, if
       “equal or better than” can be defined?
   ●   Exception on a remodel/expansion if condenser is not being replaced?



                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Remote Condenser Specific Efficiency
●   Minimum specific efficiency (BTU/Hr per watt) for air cooled
    condensers of 70 BTUh/W, calculated at 10 F TD. Maximum fin
    spacing of 10 FPI.
                 Savings (kWh)                                    10,942
                   Savings ($)                                    $1,313
               Measure Cost ($)                                   $8,800
              Maintenance Cost ($)                                  $0
               Simple Payback                                      6.7
●   Savings are compared vs. a reference baseline with floating head
    pressure and variable speed fan control (previous measure).
●   Savings compared with 50 BTU/W, which is the average of
    condensers installed in recent years, which were below 70 BTUh/W.
●   Cost based on going from 50 to 90 BTUh/W since a compliant model
    would be an available model better than 70 BTUh/W.

               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Remote Condenser Specific Efficiency
● Evaporative condenser and fluid cooler standards
  still being evaluated, but generally offer more
  flexibility by adjusting fan hp.




           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Remote Condenser Specific Efficiency
                                                          Manufacturer A
               $120

               $100
Cost ($/MBH)




                $80

                $60

                $40                                                         y = 0.2106x + 36.041
                                                                                 R² = 0.8277
                $20

                $0
                      0           20          40           60         80          100        120      140         160
                                                         Specific Efficiency (Btuh/Watt)


                      EC Motors        1.5 HP 1140 RPM     1.5 HP 830 RPM     1 HP 830 RPM    0.5 HP 540 RPM




                           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes            09/22/2010
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Remote Condenser Specific Efficiency
                                                        Manufacturer C
                 $70


                 $60


                 $50
  Cost ($/MBH)




                 $40


                 $30

                                                                            y = 0.0144x + 34.281
                 $20
                                                                                 R² = 0.0029

                 $10


                 $0
                       0           20        40         60         80           100     120        140         160
                                                     Specific Efficiency (Btuh/Watt)


                           0.5 HP, 575 RPM                1 HP 850 RPM                   1 HP 850 RPM
                           1.5 HP 1140 RPM                1.5 HP 1140 RPM                1.5 HP 850 RPM
                           1.5 HP 850 RPM                 1.75 HP 1050 RPM EC            1.75 HP 1050 RPM EC


                             CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes            09/22/2010
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Remote Condenser Specific Efficiency
                                                        Manufacturer D
                $80

                $70

                $60
 Cost ($/MBH)




                $50

                $40

                $30
                                                               y = 0.1562x + 27.194
                                                                      R² = 0.15
                $20

                $10

                $0
                      0            20              40              60              80             100        120
                                                    Specific Efficiency (Btuh/Watt)



                          0.5 HP 550 RPM   1 HP 850 RPM    2 HP 1140 RPM   0.75 HP 1075 RPM    EC Motors




                            CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes       09/22/2010
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Remote Condenser Specific Efficiency
                                                     Manufacturer E
                $60


                $50


                $40
 Cost ($/MBH)




                $30                                                           y = 0.1405x + 28.881
                                                                                   R² = 0.8813

                $20


                $10


                $0
                      0   20       40         60           80         100        120      140        160   180
                                                   Specific Efficiency (Btuh/Watt)

                                0.33 HP 550 RPM        1.5 HP 1140 RPM        1 HP 850 RPM




                          CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes         09/22/2010
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Remote Condenser Specific Efficiency
● Discussion:
   ●   Very large range of specific efficiencies appears to make this an obvious
       efficiency measure.
   ●   Necessary to establish maximum fin density (proposed at 10 FPI), which
       is generally consistent with chain specifications and contractor practice
       for supermarkets.
   ●   However, new condensers models with EC motors are among the lowest
       specific efficiencies; using higher HP motors and kW input than previous
       models with induction motors. EC motors possibly have option to be
       applied with higher specific efficiency by limiting maximum speed.
● Test and rating standards and certification:
   ●   Condensers ratings do not reference standards and are not certified.
   ●   Standard will be difficult without standards and certification, particularly
       with EC condensers having lowest specific efficiencies and highest cost.




                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Remote Condenser Specific Efficiency
● Code exceptions:
   ●   Combination air-evaporative condensers.
   ●   Remodel/expansion if condenser is not being replaced?
   ●   Small systems with design heat of rejection less than 150,000 BTU/Hr.
   ●   Micro-channel condensers exempt from fin spacing?




                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Floating Suction Pressure
●   Controls on compressor systems to allow suction pressure to float
    based on fixture and/or walk-in box temperature setpoint rather
    than fixed suction pressure control. Other temperature controls on
    selected “float” system(s) must be secondary to floating suction
    control.
                 Savings (kWh)                                   16,433
                   Savings ($)                                   $1,972
               Measure Cost ($)                                  $2,400
              Maintenance Cost ($)                                $600
               Simple Payback                                      1.7

●   Savings includes 40% reduction to allow for imperfect control system
    operation compared with simulation results.
●   Annual maintenance cost allows for cost of setpoint verification
    and/or periodic recommissioning of controls.


                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Floating Suction Pressure
● Applies to multiple compressor systems and variable capacity
  single compressors satellite systems on racks.
● Most chains have included floating suction pressure for many
  years, but results vary.
● Savings depend on effort applied to system design, fine-
  tuning during start-up and ongoing maintenance. Electronic
  suction regulators require greater control sophistication.


● Code exceptions:
   ●   Single compressor systems with on-off control.
   ●   Remodel/expansion if compressor system is not being replaced?




                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Mechanical Subcooling
● Liquid subcooling to 50 F or lower at design SCT on all low
  temperature compressor systems through use of a subcooling
  heat exchanger connected to a medium temperature
  refrigeration system or connected to the economized port on
  a low temperature compressor designed to include
  economizer subcooling.
● Applies to multiple compressor systems and variable capacity
  single compressors satellite systems on racks.

               Savings (kWh)                                   18,252
                 Savings ($)                                   $2,190
             Measure Cost ($)                                  $5,900
            Maintenance Cost ($)                                $300
             Simple Payback                                      3.1

             CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Mechanical Subcooling
● Savings allows for 5 F temperature rise from subcooler to
  refrigerated loads, plus 20% reduction in savings to allow for
  control variations vs. simulation results.
● Mechanical subcooling has been in common use by most
  chains for decades, and has greater savings with HFC
  refrigerants than with HCFC-22. Cost is minimal for the
  mandatory configuration in that net compressor horsepower
  of a central rack system decreases.


● Code exceptions:
   ●   Single compressor systems.
   ●   Low temperature systems using direct CO2 refrigerant.
   ●   Low temperature systems with a design SCT of 70 F or below.
   ●   Remodel/expansion if compressor system is not being replaced?

                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Evaporator Coil Specific Efficiency
●   Proposed measure to require minimum specific efficiency (BTU/Hr
    per watt) for evaporator coils. Savings opportunity appeared large
    due to wide range of specific efficiency, but:
●   Example of three coil models in one product line, all with two fans:
                                    Specific
                Capacity Fan Watts Efficiency                    CFM         Airside TD
                    9,000              118               76         1,300              6.4
                    7,500              118               64         1,300              5.3
                    6,500              118               55         1,400              4.3
●   Findings:
     ●   Airflow (i.e. airside temperature difference) is a variable in product lines,
         causing much of the observed range in specific efficiency.
     ●   Eliminating inefficient models could often cause selection of larger
         models with increased cost and no reduction in fan power.


                   CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Evaporator Coil Specific Efficiency
●   Manufacturers could produce more efficient models through
    redesign with different fan blades and/or motors rather than using
    “excess air” and other modifications.
●   Test and rating standards and certification:
     ●   Evaporator ratings do not reference standards and are not certified.
     ●   Standard will be difficult without standards and certification.
●   Conclusions:
     ●   Additional study including lab testing is required before rules can be
         adopted.
     ●   Test and ratings standards and certification would be required since
         product lines would require redesign. Field measurement is not feasible.
● Priority vs. variable speed control:
     ●   Use of variable speed control would reduce the potential savings from
         higher specific efficiency and vice-versa. Variable speed is more easily
         implemented than a specific efficiency standard.


                  CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Evaporator Coil Variable Speed Control
●   Variable speed control of walk-in evaporator fans as the primary
    means of temperature control in freezers and coolers Requirements
    also apply to indirect cooling coils, e.g. glycol and CO2. Other
    temperature controls, including suction regulator valves, on-off
    liquid solenoids and floating suction control would not act until
    variable speed control is at minimum speed.
●   Low and medium profile evaporator coils use EC motors (with limited
    exceptions on larger coils) and offer potential of simple, low-cost
    inherent speed control.
●   Applies to multiple compressor systems and variable capacity single
    compressors satellite systems on racks.
●   Evaporators connected to single compressor systems would be
    required to use reduced speed (i.e. two speed) or fan duty-cycling
    during the compressor off-cycle period.



               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Evaporator Coil Variable Speed Control
●   Savings assumes a minimum speed of 70%.
●   Simulation included forced speed increases, plus an additional 20%
    reduction in savings was allowed to address typical control system
    variations.
                Savings (kWh)                                   18,966
                  Savings ($)                                   $2,276
              Measure Cost ($)                                  $9,600
             Maintenance Cost ($)                                $800
              Simple Payback                                      6.5

●   Savings for medium profile coils (e.g. large point-of-sale boxes) yet
    to be evaluated, and are expected to have shorter payback.
●   Cost is a rough estimate, since pricing has not yet been obtained
    from manufacturers. Additional research in progress.



                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Evaporator Coil Variable Speed Control
●   Current availability:
●   Low profile evaporator coils: 1-2 manufacturers
●   Medium profile coils: 2-3 manufacturers


●   Uncertain how control would be provided: could be through the
    “rack” controller to integrate suction regulators and floating suction
    pressure, or using a distributed controller.


●   Code exceptions:
     ●   Evaporators for single compressor systems; use two-speed or duty-cycle.
     ●   Exception on a remodel/expansion if evaporator coils and associated
         refrigeration system is not being replaced, since speed control must be
         coordinated with suction circuit and rack controls.




                  CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Liquid-Suction Heat Exchangers
●   Proposed requirement for liquid-suction heat exchangers on direct
    expansion display cases line-ups and walk-ins, to provide 17°F of
    subcooling on LT systems at 55°F entering liquid temperature, and 7°
    F of subcooling on MT systems at 75°F entering liquid temperature.
                                 MT Cases          MT Walk-Ins          LT Cases            LT Walk-Ins
        Savings (kWh)                                                    14,768                4,768
          Savings ($)                                                    $1,772                 $572
      Measure Cost ($)                                                   $2,600                $1,000
     Maintenance Cost ($)                                                  $0                    $0
       Simple Payback                                                      1.5                   1.7
●   Savings include adjustment for compressor return gas temperature
    and LT LSHX performance assumes mechanical subcooling as the
    reference baseline.




                 CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes         09/22/2010
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    Liquid-Suction Heat Exchangers

Tout (Liquid)                                                                                    Tin (Liquid)




 Tin (Vapor)                                                                                     Tout (Vapor)




    ●     Increases system capacity by providing liquid subcooling.
    ●     Less non-productive suction line cooling, including un-evaporated
          liquid out of cases. Allows tighter superheat settings.
    ●     Helps maintain stability with floating head pressure by subcooling to
          avoid flash gas at expansion valve.
    ●     May become a no-cost option when impact on capacity if fully
          understood.


                      CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
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Liquid-Suction Heat Exchangers
●   Savings assumes properly operating superheat controls, which likely
    understates the savings achieved by minimizing overfeeding of
    liquid, particularly on close-approach medium temperature display
    cases.
●   The increased use of refrigerants with high glide (e.g. 407x) will
    realize a greater value from liquid-suction heat exchangers.


●   Code exceptions:
     ●   Primary refrigeration systems on indirect system (due to wider range of
         possible refrigerants and system types)
     ●   Display cases or evaporators with design SST higher than 30 F.
     ●   Systems using direct CO2 refrigerant.
     ●   Low temperature systems with a design SCT of 70 F or below.
     ●   Remodel/expansion if display case line-up or walk-in evaporator is not
         being replaced.


                  CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                                 46




Liquid-Suction Heat Exchangers
● Requirement for display cases anticipates a LSHX for each
  case line-up. Individual heat exchangers within each case is
  possible as well, although the liquid line heat loss within the
  case piping may defeat the purpose or require insulation.
  Since leaving refrigerant conditions are not defined in the
  Federal display case requirements, a LSHX could be used by
  the display case manufacturer to achieve the Federal standard
  for the individual display case. Many display cases use a
  nominally sized LSHX or solder the liquid and suction lines
  together. The code requirement for degrees of subcooling
  would be total for published subcooling included in the
  display case (if any) and the display case line-up LSHX.




             CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                                 47




Display Case LED Lights
● Proposed requirement for LED lights in display fixtures in
  reach-in glass door freezers and coolers, including factory
  made display cases and field-installed doors for point-of-sale
  walk-ins.
● LED lights in reach-in freezer cases in common use. Reach-in
  coolers and doors for point-of-sale freezer and cooler walk-
  ins also readily applied.
● Results for low temperature reach-in doors:

              Savings (kWh)                                   78,123
                Savings ($)                                   $9,375
            Measure Cost ($)                                 $22,000
           Maintenance Cost ($)                                 $0
            Simple Payback                                     2.3

             CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                                 48




Display Case LED Lights
● LED options for medium temperature display cases have far
  greater variations and appear to be still in development (color
  issues).
● Results for medium temperature upright open cases:

               Savings (kWh)                                     28,365
                 Savings ($)                                     $3,404
             Measure Cost ($)                                   $25,500
            Maintenance Cost ($)                                   $0
             Simple Payback                                       7.5

● Costs for open cases vary widely (or information is
  misunderstood).
● Savings based on 24 hour store.


             CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                                   49




Display Case LED Lights
● Code exceptions:
   ●   Exception on a remodel/expansion if existing display cases or
       walk-in point-of-sale doors are being reused.
   ●   Question on used fixtures purchased used or relocated from
       another store. Some retrofits are being done in existing stores,
       indicating economics may justify upgrading used cases. More
       research required.




● Timing consideration: LED technology is advancing rapidly.
  Effective date for 2011 Title 24 Standard is January 1, 2013.




               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                                                                                50




Display Case LED Lights

                T-8 and LED Watts per Door                                      T-8 and LED Watts per Row
                      by Manufacturer                                                 by Manufacturer
         79.9




                                                                                                                 9.2
90                                                                  10
                  72.0

                         69.6


80                                                                   9




                                                                             7.4
                                                                            7.2
                                                                     8




                                                                           7.0


                                                                                        6.9
70
                                                                     7
60




                                                                                                           5.4

                                                                                                                       5.3
                                                                     6




                                                                                                                                    4.5
50




                                                                                              4.1
                                                                     5
                                           27.6




                                                                                                                              3.5
                                                  27.0

40                                                       23.0        4




                                                                                                    3.0




                                                                                                                                          2.2
30                                                                   3
20                                                                   2
10                                                                   1
 0                                                                   0
     Reach-in T-8 W/Door Reach-in LED W/Door                             Canopy T-8 Canopy                Shelf T-8          Shelf LED
                                                                            W/f t   LED W/f t               W/f t              W/f t




                                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes                        09/22/2010
                                                                                                    51




Display Case Lighting Controls
● Proposed requirement for automatic controls to turn off
  display case lights on non-24 hour stores.

                 Savings (kWh)                                     82,349
                   Savings ($)                                     $9,882
               Measure Cost ($)                                    $4,000
              Maintenance Cost ($)                                  $100
               Simple Payback                                        0.4
● Includes 20% reduction in savings vs. simulation results to
  allow for overrides and improper settings.


● Code exceptions:
   ●   Allow timed override switches with a minimum of two zones to allow
       lights to operate for case stocking during non-business hours.

                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                               52




No Open Upright Freezers
● Proposed rule to prohibit use of open upright
  freezer cases.
● No recent stores (based on Savings By Design
  experience) use open upright freezer cases.
● Additional analysis in progress.




● Discussion: are there reasons to allow use of open
  upright freezer cases for certain applications?

           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                                     53




Reach Codes
● Optional codes for:
   ●   Jurisdictions
   ●   Program requirement
● Basis for next round of code updates
● Two levels of efficiency:
   ●   Tier I      15% beyond the Base Code
   ●   Tier II     30% beyond the Base Code




                 CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                                    54




Demand Defrost (Reach Code)
●   Evaluation of possible prohibition of gas defrost and required use of
    demand defrost controls in conjunction with electric defrost and
    trunk piping.
●   Purpose of energy evaluation is to determine the increased energy
    with this measure vs. the benefit of reduced HFC leakage.

               Electric Defrost kWh                              29,691
                  Savings (kWh)                                  12,145
                    Savings ($)                                  $1,457
                Measure Cost ($)                                $12,900
               Maintenance Cost ($)                              $1,000
                 Simple Payback                                   28.2

●   Analysis assumes 60% reduction in defrost frequency and improved
    defrost efficiency at each defrost (since more ice is accumulated).
●   No credit is taken yet for lower RGT with trunk piping.

                CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                               55




Demand Defrost (Reach Code)
● Demand defrost controls have been used in the
  past but are not currently in use in supermarkets.
  Availability is limited.
● The potential requirement of electric defrost (or
  prohibiting gas defrost) should be evaluated vs.
  fixed-time electric defrost control.




           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                                   56




Heat Reclaim for Space Heating (Reach Code)

● Proposed requirement for heat recovery from refrigeration to
  provide at least 25% of the design refrigeration heat of
  rejection for space heating, while increasing the refrigerant
  charge by no greater than 20% or 0.50 lbs per 1,000 BTU/Hr
  of heating capacity, whichever is less.
● Analysis for a full heat recovery system in an large
  supermarket using Sacramento weather:

             Savings (Net) ($)                                  $8,329
             Measure Cost ($)                                  $30,000
            Maintenance Cost ($)                                $1,000
             Simple Payback                                      4.1
● Code exceptions:
   ●   Remodel/expansion when compressor system is not being replaced.


               CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                               57




No Open Upright Cooler Cases (Reach Code)

● Possible future Reach Code to require glass doors
  on all open upright cooler cases.
● Detailed study is required to determine energy
  savings, as well as understand the impacts on store
  design, operations, and other factors. Additional
  analysis to being considered.




● Discussion: what factors need to be considered in
  addition to energy analysis?
           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010
                                                                                               58




Next Steps

● Refinement of measure list
● Measure life-cycle cost effectiveness analysis




           CA Utilities 2011 Title 24 Stakeholder Meeting for Proposed Code Changes   09/22/2010

				
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