Transcript REF WHS Stakeholder Meeting 1

1
Refrigerated Warehouses
Stakeholder Meeting #1
California Statewide Utility Codes and Standards Program
Portland Energy Conservation, Inc.
VaCom Technologies
Heschong Mahone Group, Inc
April 15, 2010
04/15/2010
Energy for Change™
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouse
2011 Title 24 Stakeholder Meeting
Welcome and Introductions
Michele Friedrich, PECI
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
2
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Agenda
●
10:00–10:20
Introduction
●
10:20–10:35
Overview/History
●
10:35–11:15
Model & Data Analysis
●
11:15-12:00
2011 Measures
●
12:00-12:45
lunch
●
12:45-2:30
2011 Measures (cont)
●
2:30-2:45
Acceptance Tests
●
2:45-3:00
Wrap up
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
3
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Ground Rules
●
For those attending by telephone/web
●
●
●
●
We want to hear your concerns.
●
●
●
Opposing viewpoints are encouraged.
We are seeking information, not resolution.
Time is limited
●
●
●
●
●
●
Please DO NOT place your phone on HOLD. We do not want to hear your
hold music.
Please mute your microphone, unless you want to speak.
Ask questions/comment by “chat” or by voice.
Hold questions/comments until the comment periods.
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 distributed.
If you are attending by phone, DO NOT place your phone on HOLD.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
4
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Schedule of Refrigerated Warehouses
Stakeholder Meetings
● There will be at least four refrigerated warehouse
stakeholder meetings:
●
March 17 and April 15, 2010: present scope, including:
●
●
●
August 2010: present findings, including:
●
●
●
●
Code change direction and possible options
Methodology of analysis
Results of data collection and analysis
Cost effectiveness
“Strawman” proposed code language
September 2010: seek final feedback on proposed code
language
● All meetings can be attended remotely.
● Please sign-in for all future meeting announcement
mailings.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
5
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouse
2011 Title 24 Stakeholder Meeting
Stakeholder Process
Cathy Chappell, HMG
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
6
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
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 standard (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.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
7
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Code Change Activity
● 2011 T-24 base code
● 2011 reach standard
●
●
Voluntary standards for local govts.
Green Building Standard
● Toward Zero Net Energy goal
●
●
2014 T-24
Future reach codes
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
8
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Requirements for a
Successful Code Change
To be included in code, a measure must:
●
●
Be cost-effective according to the Time
Dependent Valuation (TDV) life-cycle
costing methodology set out by the
California Energy Commission (CEC)
Be possible to implement using
equipment that is readily available from
multiple providers (or that is reasonably
expected to be available following the
code change).
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
9
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Schedule: CEC Key Dates
● Mar 2010 - Dec 2010
●
●
CEC develop foundation
IOUs:
●
●
Conduct research, and cost effectiveness analysis
Present results at stakeholder meetings
● Dec 2010
●
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
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
10
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Stakeholder Meetings Purpose
● Publicize code change proposal
● Present to and solicit feedback from stakeholders
on:
●
●
●
●
Methodology
Technology options
Market status
Draft code language
● Gather additional information from stakeholders
on:
●
●
●
●
Best practices
Product/technology availability
Market penetration data
Cost data
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
11
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Specific Stakeholders Identified
● ASHRAE- American Society of Heating, Refrigerating and Air
●
●
●
●
●
●
●
●
●
●
●
●
●
Conditioning Engineers
AHRI- American Heating And Refrigeration Institute
IIAR- International Institute Of Ammonia Refrigeration
GCCA – Global Cold Chain Alliance (IARW, IACSC)
Equipment manufacturers
Consultants, energy modelers, etc
Refrigerated warehouse building owners
City and County code officials
Equipment distributers and suppliers
Refrigerated warehouse designers
Investor Owned Utilities
California Energy Commission
California Air Resources Board
Non Governmental Organizations
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
12
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 CASE Process Overview
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
13
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouse
2011 Title 24 Stakeholder Meeting
Overview of 2008 Title 24 for
Refrigerated Warehouses (§ 126)
Michele Friedrich, PECI
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
14
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Overview of 2008 T24 (§ 126)
Applicability
● Refrigerated Warehouse with Cold or Frozen
Storage > 3,000 ft2
Exceptions
● Appliance efficiency (Title 20) applies to
refrigerated space < 3,000 ft2
● Areas designed solely for quick chilling or
freezing
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
15
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Overview of 2008 T24 (§ 126)
Insulation
SPACE
Frozen
Storage
Cold
Storage
SURFACE
Min R-VALUE
(°Fhrft2/BTU)
Roof/Ceiling
R-36
Wall
R-36
Floor
R-36
Roof/Ceiling
R-28
Wall
R-28
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
16
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Overview of 2008 T24 (§ 126)
Underslab Heating
● Electric resistance heat shall not be used for
the purposes of underslab heating.
● Exception: Thermostatically controlled and
disabled during summer on-peak period
defined by local utility.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
17
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Overview of 2008 T24 (§ 126)
Fan-powered Evaporators
● Single-phase fan motors < 1 HP and < 460 V
shall be electronically commutated motors
(ECM).
● Fans shall be variable speed, speed
controlled in response to space conditions.
●
Exception: evaporators served by a single
compressor without unloading capability.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
18
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Overview of 2008 T24 (§ 126)
Fan-powered Condensers
● Condensers for ammonia systems
shall be evaporatively cooled.
● Design condensing temp for
evaporative condenser < design
Twetbulb plus:
●
●
●
20F when design Twetbulb ≤ 76F,
19F when 76F< design Twetbulb < 78F
18F when 78F ≤ design Twetbulb
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
19
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Overview of 2008 T24 (§ 126)
Fan-powered Condensers
● Design condensing temperatures for
Air-cooled condensers:
●
≤ the design drybulb temperature plus
10F for frozen storage.
●
≤ the design drybulb temperature plus
15F for cold storage.
● Exception: Unitary condensing units
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
20
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Overview of 2008 T24 (§ 126)
Fan-powered Condensers
● Condenser fans shall be continuously
variable speed and the speed of all
condenser fans serving a common high side
are controlled in unison.
● Min condensing temperature set point 70F
or less using ambient reset control
●
●
air-cooled reset based on drybulb temp
evap-cooled reset based on wetbulb temp
● All single phase motors < 1 hp and < 460 V,
either permanent split capacitor or ECM.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
21
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Overview of 2008 T24 (§ 126)
Compressors
● Compressors designed to operate at a
minimum condensing temperature ≤ 70F
● Screw compressor > 50 HP
● Speed control in response to load OR
● Input power ≤ 60% of full load power at
50% of full refrigeration capacity.
● Exception: refrigeration plants with more
than one dedicated compressor per
suction group
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
22
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Information on 2008 Refrigerated
Warehouse Standard
● Classes on 2008 Standard
SCE: August 2, CTAC- Irwindale
● Energy Efficiency Hotline
●
E-mail: [email protected]
●
Phone: 916-654-5106 or
●
Phone: 1-800-772-3300 (toll free in Calif.)
● Title 24 website
www.energy.ca.gov/title24/
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
23
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouse
2011 Title 24 Stakeholder Meeting
Building Models and Assumptions
Brian Dobbs, VaCom Technologies
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
24
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Data Analysis Overview
● Savings calculated with DOE2.2R
● Whole-building/system hourly simulation tool
●
Mass-flow based
● Designed for component/control strategy
level modeling
●
Explicit simulation of most refrigeration control
strategies
● Hourly weather file
● Hourly DBT, WBT, wind velocity, solar
● Hourly schedules
● Loads, operations, set-points
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
25
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Data Analysis Overview
● DOE2.2R allows detailed simulation of
building envelope
●
Building constructions
●
Define materials and thermal properties
●
Calculates roof and wall load
●
Accounts for building configuration
●
Orientation, adjacent spaces
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
26
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Data Analysis Overview
● Details of space definitions
● Simulates infiltration load using:
●
●
●
●
●
Lighting and lighting controls can be defined
Miscellaneous equipment loads can be added
●
●
ASHRAE methodology for interzonal air exchange
(density difference)
Wind velocity adjusted external infiltration
Hourly activity schedules
Process loads
Evaporator fan
●
●
Power usage
Controls (VFD, fan cycling)
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
27
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Data Analysis Overview
● Example of Hourly Schedule Inputs
120%
100%
80%
60%
40%
20%
People
8:
00
AM
10
:0
0
AM
12
:0
0
PM
2:
00
PM
4:
00
PM
6:
00
PM
8:
00
PM
10
:0
0
PM
AM
AM
6:
00
AM
4:
00
2:
00
12
:0
0
AM
0%
Lighting
Equipment
2011 Refrigerated Warehouse Stakeholder Meeting
Infiltration
04/15/2010
28
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Data Analysis Overview
● Detail equipment operation
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
29
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Data Analysis Overview
● Energy usage summary and break-outs
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
30
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Data Analysis Overview
● Utility usage summary and break-outs
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
31
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Data Analysis Overview
● Initial Analysis: Sacramento weather
● Baseline simulation models:
●
●
Large warehouse (92,000 ft2)
●
Screw compressors
●
R-717 refrigerant
●
Evaporative-cooled condenser
Small warehouse (26,000 ft2)
●
Semi-hermetic compressors
●
R-404A refrigerant
●
Air-cooled condensers
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
32
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Baseline Warehouse Description
● Freezer Space
●
●
●
●
40,000 S.F. (Large Warehouse)
10,000 S.F. (Small Warehouse)
-10°F space temperature
R-36 insulation
● Cooler Space
●
●
●
●
40,000 S.F. (Large Warehouse)
10,000 S.F. (Small Warehouse)
35°F space temperature
R-28 Insulation
● Loading Dock
●
●
●
●
12,000 S.F. (Large Warehouse)
6,000 S.F. (Small Warehouse)
40°F space temperature
R-28 insulation
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
33
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Warehouse Diagrams
Small Warehouse
Large Warehouse
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
34
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Large Warehouse System Description
LT Suction Group
● Serves Freezer space
● -23°F design SST
● (2) screw compressors, 62.5 TR capacity, 165 HP each at design
● Evaporator fan power calculated using 34 Btuh/W spec efficiency
● MT Suction Group
● Serves Cooler and Dock spaces
● 22°F design SST
● (2) screw compressors, 110.2 TR capacity, 134 HP each at design
● Evaporator fan power calculated using 34 Btuh/W spec efficiency
● Evaporative-cooled Condenser
● 6,400 MBH capacity at design TD = 23°F (96°F design SCT, 73°F
design WBT)
● 330 Btuh/Watt specific efficiency at 100°F SCT, 70°F WBT
● 70°F minimum SCT, wetbulb-following SCT control, variable
speed fans working in unison
●
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
35
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Small Warehouse System Description
● Low-Temperature (Freezer) System
●
●
●
●
●
-23°F design SST, 114°F design SCT
(8) Semi-hermetic compressors
Air-cooled condensers, 10°F design TD, 53 Btuh/Watt
70°F minimum SCT, drybulb-following control strategy,
variable-speed fans
Evaporator fan power calculated using 34 Btuh/Watt
● Medium-Temperature (Cooler and Dock) System
●
●
●
●
●
22°F design SST, 119°F design SCT
(4) Semi-hermetic compressors
Air-cooled condenser, 15°F design TD, 53°F Btuh/Watt
70°F minimum SCT, drybulb-following control strategy,
variable-speed fans
Evaporator fan power calculated using 34 Btuh/Watt
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
36
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Screw Compressor Performance
● Model in large warehouse only
● Convert two-compressor suction group to singlecompressor
● LT and MT system evaluated
● Slide valve part-load performance from
manufacturer’s software
● Speed reduction part-load performance
from manufacturer’s software
●
●
Speed reduction down to minimum speed, then
slide valve unloading
Analysis includes 3% fixed drive losses
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
37
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Screw Compressor Performance
● Sample Part-load Relation
Percent of Capacity
Full Load (%)
(TR)
100%
378.2
90%
340.4
80%
302.5
70%
264.7
60%
226.9
50%
189.1
40%
151.3
30%
113.5
20%
75.6
10%
46
Power
(BHP)
894.1
841
788.4
736.8
687
639.7
595.4
555
519
494.3
2011 Refrigerated Warehouse Stakeholder Meeting
Performance
Factor (TR/BHP)
0.423
0.405
0.384
0.359
0.330
0.296
0.254
0.205
0.146
0.093
04/15/2010
38
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Warehouse Load Description
Large Warehouse
Small Warehouse
Lights
0.70 Watts/S.F., all spaces
0.70 Watts/S.F., all spaces
People
1,500 S.F., 1,450 Btuh per person
1,500 S.F., 1,450 Btuh per person
Forklifts
30 forklifts (20 MBH ea), 10 pallet
lifts (10 MBH ea), distr. by SF
10 forklifts (20 MBH ea), 3 pallet lifts
(10 MBH ea), distr. by SF
Product Load
Freezer: 400,000 lb/day, 5°F
pulldown, 0.50 Btuh/(lb °F) specific
heat
Freezer: 100,000 lb/day, 5°F
pulldown, 0.50 Btuh/(lb °F) specific
heat
Cooler: 400,000 lb/day, 10°F
pulldown, 0.65 Btuh/(lb °F) specific
heat PLUS 750 tons respiring
product, 5,500 Btuh/ton heat of
respiration
Cooler: 100,000 lb/day, 10°F
pulldown, 0.65 Btuh/(lb °F) specific
heat PLUS 188 tons respiring
product, 5,500 Btuh/ton heat of
respiration
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
39
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Warehouse Load Description
Infiltration
Large Warehouse
Small Warehouse
4,000 CFM (200 CFM/dock door,
subject to hourly schedule and wind
effects).
1,200 CFM (200 CFM/dock door,
subject to hourly schedule and wind
effects).
Assume inter-zonal doors between
Dock and Cooler/Freezer open 15
times per hour each (once every
four minutes)
Assume inter-zonal doors between
Dock and Cooler/Freezer open 15
times per hour each (once every
four minutes)
Assume inter-zonal door between
Cooler and Freezer opens 4 times
per hour (once every 15 minutes.
Assume inter-zonal door between
Cooler and Freezer opens 4 times
per hour (once every 15 minutes.
Assumed inter-zonal door opening
time: 5 seconds to open/close, 15
second stand-open time, 20 seconds
total open time per opening
Assumed inter-zonal door opening
time: 5 seconds to open/close, 15
second stand-open time, 20 seconds
total open time per opening
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
40
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Refrigerated Warehouses
Building Model and Assumptions
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
41
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouse
2011 Title 24 Stakeholder Meeting
2011 Enhancements of Title 24 for
Refrigerated Warehouses
Doug Scott, VaCom Technologies
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
42
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouse
2011 Cycle Title 24 Measures
Base Code (2011)
●
●
●
●
●
●
Freezer Floor and Roof Insulation R-values
Evaporator Specific Efficiency (BTUh/W)
Condenser Specific Efficiency (BTUh/W)
Ammonia System Air-cooled Condensers
Screw Compressor Part-load Performance
Acceptance Tests
Reach Code
●
Condensing Unit EER (BTUh/W)
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
43
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2008 Refrigerated Warehouse
Insulation Analysis Summary
Shell Component
Freezer
Cooler
Ceiling
Wall
Floor
Ceiling
Wall
ASHRAE
2002
Handbook
Common
Practice
R-35 to 50
R-35 to 40
R-27 to 32
R-24 to 40
R-24 to 32
R-46
R-32
R-30
R-24 to R-40
R-25
2008 CASE Study Findings
Benefit/Cost Ratio
2008 CASE
Central
Coastal
Recommendation
Valley (CZ
(CZ 3)
13)
R-49
R-40
R-30
R-35
R-25
3.7
1.9
4.8
1.1
0.6
4.3
2.2
5.0
2.0
1.1
However, 2008 Standard R-values selected to
matched Title 20 Standard for walk-ins
2008 freezer roof and floor: R-36
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
44
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Freezer Roof and Floor
Insulation Measures
● Investigate cost-effectiveness of additional
freezer roof insulation
●
Greater choices for refrigerated warehouses Rvalues than for foamed-in-place walk-in panels
● Investigate cost-effectiveness of R-36 floor
insulation vs. a lower level, consistent with
standard increment of extruded polystyrene
under slab insulation
● Make analysis and requirements consistent
in terms of rating temperature (applied
temperatures or ~75 F) and new vs. aged
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
45
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Freezer Roof and Floor
Insulation Analysis
● Increase freezer roof insulation
incrementally from R-36 to ~R-50
● Decrease freezer floor insulation
incrementally from R-36 to ~R-24
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
46
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Freezer Roof and Floor
Insulation Data Summary
● Obtain details on common insulation size
increments and incremental costs for:
●
●
●
Underfloor extruded polystyrene
Common over-deck insulation compositions
EPS and ISO sandwich roof/ceiling panels.
● Determine assumptions for insulation rating
temperature and aged vs. new R-value
● Verify FIP panels can meet requirement
● Identify other constructability issues
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
47
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Freezer Roof and Floor
Insulation Data Collection Tasks
● Contact:
● Cold storage construction contractors
● Insulation and panel manufacturers
● GCCA/IACSC (Intl Assn for Cold Storage Const.)
● Extract information from past new
construction projects
● Review requirements in Fed WI Test
Standard for testing consistency
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
48
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Freezer Roof and Floor
Insulation
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
49
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Evaporator Specific Efficiency
Code Change Options
● Specific Efficiency = Cooling capacity at a
standard rating value divided by power.
●
Rating point: 10°F TD between entering air
temperature and saturated suction; doesn’t
mean this is the applied TD
● Very large range of specific efficiencies.
● High potential savings simply by eliminating
the least efficient (high fan power) models,
which are not normally used in well
engineered systems.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
50
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Evaporator Specific Efficiency
Code Change Options
● Savings is the improvement from below
●
●
●
●
●
minimum up to minimum efficiency
Easy to justify excluding worst performing
models. BUT:
This cannot be done properly without test
standards and certified ratings for BOTH
cooling capacity and power.
No evaporators currently state testing to
standards and none indicate certification.
Requires changes to existing standards.
Changes caused by evaporator testing and
certification are potentially far-reaching.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
51
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Evaporator Specific Efficiency
Issues with Ratings
● Evaporator ratings, especially in smaller
sizes, generally thought to be significantly
commercialized.
● Fan power often not listed, available upon
request but may be nominal motor power,
not applied power.
● AHRI Standard 420 tests at reasonable
conditions but some issues (e.g. freezer coil
rated with no frost).
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
52
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Evaporator Specific Efficiency
Air Circulation Volume, RH, Defrosts
● Air circulation volume and cooling capacity are
not generally independent design parameters;
airflow usually an unmanaged consequence of
coil selection for cooling capacity and price.
● Evaporator are selected to maintain
temperature and frequently also humidity;
industry has experience-driven practice to
achieve proper humidity – typically via coil TD
but essentially airflow vs. capacity.
● Industry has experience with TD and FPI (fins
per inch) for satisfactory defrosts: which
indirectly affects airflow and specific efficiency.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
53
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Evaporator Specific Efficiency
Analysis and Rating Issues
● Refrigerants and fluids: NH3, halocarbon, volatile indirect (e.g.
●
●
●
●
●
●
●
●
●
CO2), single phase indirect (e.g. glycol)
Application temperature: two temperatures not enough for
rating standards for all application conditions
External static pressure: accommodate penthouse coils but
not oversized motors or excessive throw
Motor loading: define at application conditions
Feed type: DX vs. recirculated or flooded
Assumptions for wet or dry; frosted or non-frosted coil
Assumptions for defrost method and efficiency
Fin density: could improve specific efficiency with more FPI
but cause excessive defrosts
Liquid-suction heat exchanger: may be most cost effective
means to increase DX coil performance
Refrigerants with glide
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
54
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Evaporator Specific Efficiency
Summary of Available data
● Savings By Design program history used to
establish beginning values:
●
Provisional minimum efficiency = 34 BTUh/W
●
Average of units purchased in California that
were below minimum efficiency = 26 BTUh/W
● Cataloged models put in database
● Evaluate European standards and test
methods for evaporators
● Obtain costs from published price lists and
sample vendor quotes
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
55
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Evaporator Specific Efficiency
Data Collection Tasks
● Contacts:
● Evaporator coil manufacturers
● Obtain European standards
● Identify and obtain any available test data to
relate catalog data to applied conditions,
frosted operation, etc.
● And/or, perform testing in lab (SCE RTTC) or in
field, particularly on DX evaporators, possibly
along with condensing unit test.
● Request info. from technical advisors
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
56
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Evaporator Specific Efficiency
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
57
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Condenser Specific Efficiency
Code Change Options
● Specific Efficiency = Heat rejection capacity
at standard rating value divided by power.
● Rating point: 10°F TD between entering air
temperature and saturated condensing
temperature; doesn’t mean this is the applied TD
● (10°F may be questionable if research
determines this is not actually being achieved)
● Midpoint between bubble point and dew point
for glide refrigerants
● Very large range of specific efficiencies.
● High potential savings simply by eliminating
the least efficient models.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
58
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Condenser Specific Efficiency
Code Change Options
● Savings is the improvement from below
●
●
●
●
minimum up to minimum efficiency.
Similar to evaporators, need test standards and
certified ratings for both capacity and power.
No condenser catalogs currently state testing
to standards and none indicate certification.
Requires changes to existing standards.
Changes caused by condenser testing and
certification are potentially far-reaching.
●
●
Air cooled: affects other applications such as
supermarket condensers
Evap cooled: affects many industrial applications
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
59
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Condenser Specific Efficiency
Issues with Evap-Cooled Ratings
● Wide range of types:
●
●
Forced draft, induced draft
Indoor location with external static
● Standards:
●
ASHRAE Standard updated in 2005 (methods)
●
AHRI test points: 78°F WBT and 105°F SCT (R-22) and
96°F (NH3) – WBT is far from normal range. Relies on
manufacturers application correction factors.
●
Cooling Tower Institute not yet investigated.
● High cost of testing and rating
● Variable speed changes low power economics
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
60
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Condenser Specific Efficiency
Issues with Air-Cooled Ratings
● Air cooled capacity historically shown with a
single Q=UATD from 1 to 30°F TD.
●
●
AHRI Standard based on 30°F TD standard test
point vs. 10°F and 15°F commercial application
(Not saying AHRI Standard is being used)
● Fan power often not listed, OEM motors,
power available upon request but may be
nominal motor power, not applied power.
● New product changes: BLDC motors
(variable speed; variable specific efficiency
by setting max speed); micro channel HX.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
61
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Condenser Specific Efficiency
Issues with Air-Cooled Ratings
● Test ratings at high SCT may not fairly
compare operation at (more common)
reduced head pressure due to internal
pressure drop at reduced pressure.
● European standards may give guidance on
defining performance for application
conditions.
● Variable speed changes economics of low
power condensers.
●
Most of year is not at reduced speed; third
power fan power reduction. Longer payback for
larger and/or low power condenser.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
62
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Condenser Specific Efficiency
Summary of Available data
● Savings By Design program history used to
establish beginning values:
● Provisional minimum specific efficiency:
●
●
●
Evap: 330 BTUh/W at 100°F SCT, 70°F WBT
Air: 53 BTUh/W at 10°F TD
Average of units purchased in California that
were below minimum efficiency:
●
●
Evap: 220 BTUh/W
Air: 44 BTUh/W
● Most cataloged models have been databased
● Evaluate European standards and test methods
● Obtain costs from published price lists, pricing
software and sample vendor quotes
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
63
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Condenser Specific Efficiency
Data Collection Tasks
● Contacts:
● Condenser manufacturers
● Obtain European standards
● Identify and obtain any available test data:
● Air-cooled, in particular 30°F vs. 10°F TD
● Evap-cooled, in particular information on
correction factors related to test/standard
basis
● Request info. from technical advisors.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
64
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Condenser Specific Efficiency
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
65
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Air-Cooled Ammonia Condenser
Code Change Options
● Allow use of air-cooled condensers on ammonia
systems.
● Potential benefits:
●
●
●
Ammonia air-cooled systems with T24 sizing and
control may have comparable annual kWh as
evap-cooled in many regions (Air-cooled has
higher peak kW.)
Water savings – important in California
Energy savings with ammonia (if air is going to
be used anyway)
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
66
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Air-Cooled Ammonia Condenser
Analysis Issues
● Evaluate a cost-effective minimum specific
efficiency; probably different than halocarbon
condensers.
● Include specific efficiency requirement and
existing VFD requirement.
● Utilize existing mandatory sizing requirements
of 10°F (low temp) and 15°F (med temp).
● Calculate water savings.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
67
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Air-Cooled Ammonia Condenser
Data Collection Tasks
● Obtain information from ammonia air-cooled
condenser manufacturers (there are two or
more).
● Obtain price quotes.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
68
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Air-Cooled Ammonia Condenser
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
69
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Compressor Part Load Efficiency
Code Change Options
● Change: Simplify 2008 screw compressor
variable speed requirement and/or the
exemption via part-load efficiency.
● Issue: Industrial screw compressor ratings are
generally not published in accordance with a
rating standard and are not certified, at either
full load or for part load performance.
● Possible change to mandatory application-
based criteria, eliminating compressor partload efficiency as a basis of compliance.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
70
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Compressor Part Load Efficiency
Analysis
● Simulation analysis to determine:
●
Threshold saturated suction temperature below
which variable speed is consistently cost
effective for single stage compressors.
●
Whether variable speed for booster compressors
(on two stage systems) is cost effective.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
71
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Compressor Part Load Efficiency
Summary of Available data
● Utilize existing manufacturers performance
software.
● Obtain additional lab test information as
available from manufacturers.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
72
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Compressor Part Load Efficiency
Data Collection Tasks
● Obtain costs from compressor manufacturers
price lists, price quotes and from VFD vendors.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
73
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Compressor Part-Load Efficiency
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
74
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Reach Code Option
Air-Cooled Condensing Unit EER
● 2008 Code exempts most unitary air-cooled
condensing units from condenser sizing (TD)
requirement.
Large air-cooled units ARE required to meet TD,
but problematic for “catalog” units since the
application conditions are not known when
designed.
● EER (Energy Efficiency Ratio) is cooling capacity
divided by input power of the entire condensing
unit (compressor and condenser fan energy).
● EER and (usually) power are not published and
capacity is generally thought to be based on
compressor ratings not unitary test standards.
●
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
75
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Reach Code Option
Air-Cooled Condensing Unit EER
● Condensing unit capacity based on compressor
standard ratings inherits a large and long
standing error:
●
●
●
Most refrigeration compressor are rated at a
fixed 65°F RGT (return gas temperature)
regardless of saturated suction.
All superheat from evaporator temperature to
65°F is assumed to be productive refrigeration.
Potential error between catalog capacity and
actual productive refrigeration can be 15-35%.
● Test data lacking on:
● Actual productive cooling capacity vs. unit rating
● Compressor performance at varying RGT
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
76
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Reach Code Option
Air-Cooled Condensing Unit EER
● EER standards must be done in parallel with
evaporator standards, to avoid causing a
mismatch.
● Capacity shortfall probably masked by rule-ofthumb load calculations and adjustment for “18
hour” run times. If system capacity ratings
decrease, equipment will be larger than before
and with less run time. Training needed to select
equipment properly under new ratings.
● EER standards would likely cause all catalogs to
change, impacting other uses.
● Compressor manufacturers will need to provide
rating data or adjustments for lower RGTs.
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
77
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Reach Code Option
Air-Cooled Condensing Unit EER
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
78
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouse
2011 Title 24 Stakeholder Meeting
Acceptance Tests
Michele Friedrich, PECI
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
79
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Acceptance Tests
● What are acceptance tests?
●
Tests performed on the building’s systems in order to
show compliance with the code.
● When are acceptance tests
implemented?
●
After start-up
●
Before normal use of the equipment
● Who can do the acceptance tests?
●
Licensed mechanical engineer, civil engineer, architect
or contractor
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
80
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
Refrigerated Warehouses
Acceptance Tests
How to show Compliance?
●
Checklist
●
Certificate of acceptance
●
Submittal of necessary
documentation
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
81
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Acceptance Tests
Development Process
1.
Post installation verification site
visits
2.
Develop preliminary version or
tests
3.
Pilot test the tests
Solicit input from stakeholders
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
82
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Acceptance Tests
Acceptance Requirements for 2008
Code
● Electric Resistance Underslab Heating
● Evaporator Fans
● Evaporative-cooled Condenser Fans
● Air-cooled Condenser Fans
● Screw Compressors
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
83
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Acceptance Tests
Comments?
Questions?
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
84
CALIFORNIA STATEWIDE UTILITIES CODES AND STANDARDS PROGRAM
2011 Acceptance Tests
Wrap Up
Michele Friedrich, PECI
2011 Refrigerated Warehouse Stakeholder Meeting
04/15/2010
85