SS 591 : 2013
Adapted for SEI/PSS
30March2015
Lee Eng Lock
Co-convenor of SS 591 : 2013 Working Group

Overview of SS 591 : 2013
Enable an organization to design and implement a measurement and verification (M&V) system for the long term, continuous and accurate tracking of the energy efficiency of central chilled water systems;
The objectives of long term, continuous and accurate tracking of energy efficiency, important process parameters and relevant performance data of central chilled water systems are to:
•
Ensure correct sizing of plant components;
•
Facilitate proper operation, maintenance, sizing, and control of the system to improve energy efficiency, and to reduce greenhouse gas emissions and water consumption;
• Allow buyers to specify energy efficiency requirements that must be met and guaranteed by suppliers, Energy Services Companies (ESCOs), contractors, and designers of equipment and systems; and
• Facilitate the reporting of the performance of the chilled water system to relevant authorities.
Information on this slide is confidential and strictly for use by SPRING Singapore officers only. It should not be used or referred to by third parties without prior written consent from SPRING Singapore.
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Section
1.
General
2.
Description of measurement and verification system
3.
Measurement and instrumentation requirements
4.
Data handling and presentation
5.
Testing and commissioning
6.
Long term and continuous monitoring
Content
• Scope
• Normative references
• Definitions
• General (Annex A)
• Data points
• Performance metrics (Annex B)
• Uncertainty and calibration
• Installation (Annex C)
• Instrument documents (Annex D)
• Data point naming (Annex E)
• Trending & storage
• Graphics display
• Checks on installation
• Demo/ witness test
• Verification
• Training & submittals (Annex F)
• Monitoring procedures
• Instrument service life
• Maintenance checklist
Overview of SS 591 : 2013
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Overview of SS 591 : 2013
 ASHRAE Guideline
14:2002
 IEEE 519:1992
Measurement of energy and demand savings




IEC 61869-2:2012
IEC 61869-3:2011
IEC 61869-5:2011
IEC 62053-22:2003
IEEE Recommended practices and requirements for harmonic control in electrical power systems
Instrument transformers - Part 2: Additional requirements for current transformers
Instrument transformers - Part 3: Additional requirements for inductive voltage transformers
Instrument transformers - Part 5: Additional requirements for capacitor voltage transformers
Electricity metering equipment (a.c.) - Particular Requirements - Part 22:
Static meters for active energy (classes 0,2 S and 0,5 S)
Measurement of liquid flow in closed conduits-weighing method  ISO 4185:1980/Cor
1:1993
 ISO 8316:1987
 ISO/IEC 17025:2005
 SS ISO 50001 : 2011
Measurement of liquid flow in closed conduits- method by collection of the liquid in a volumetric tank
General requirement for the competence of testing and calibration laboratories
Energy management systems- Requirements with guidance for use
Information on this slide is confidential and strictly for use by SPRING Singapore officers only. It should not be used or referred to by third parties without prior written consent from SPRING Singapore.
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Overview of SS 591 : 2013
• Lists the data points where measuring instruments shall be supplied and installed to monitor at 1 minute interval and trended over the entire life-cycle of the chilled water system.
Minimum Requirements
Temperature
Flow
CHW & CDW Header return/supply temperature
CHW & CDW Header flow
Power
Weather
Station
Group of equipment (chillers,
CHW & CDW pumps and cooling towers)
Dry-bulb air temp and RH
Minimally 1 set along the cooling towers
Recommended Requirements
Temperature
Flow
Power
CHW & CDW return/supply temperature at individual chillers
CHW & CDW flow at individual chillers
Power at individual equipment
Minimum requirement
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Overview of SS 591 : 2013
•
Provides the uncertainty of each measurement system as well as the overall uncertainty under laboratory conditions
Measurement System
Maximum allowable uncertainty (%)
(includes sensor and
(calibration under laboratory condition) data acquisition system)
Temperature
Flow
Power
Overall
Each temperature measurement system: ± 0.05
⁰ C .
Between the supply and return of the chilled or condenser water:
(0.05

C )
2 
(0.05
5.5

C

C )
2

100 %
 ± 1.3
± 1
± 2
Overall maximum allowable uncertainty of the M&V system :
1 .
3
2 
1
2 
2
2  ± 2.6
*Recommends that the calibration facilities meet the requirements of ISO/IEC 17025: 2005
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Overview of SS 591 : 2013
clauses 3.1.4 to 3.1.6 Requirements for each measurement system
•
Provides the uncertainty requirements and testing standards for each measurement system
– temperature, power and flow
Measurement System Important clauses
Temperature
Each temperature sensors shall be individually calibrated against a measurement standard with a maximum uncertainty rating of ±0.01
⁰
C.
Flow
Power
All tests conducted to measure the uncertainty of the flow measurement system shall be in accordance with ISO 4185:1980/Cor 1:1993, ISO
8316:1987 or equivalent test standards.
Type-test reports can be accepted as long as they demonstrate that the requirements in 3.1.5.3 (above) have been met.
All tests conducted to measure the uncertainty of power meters and their associated current and voltage transformers used in the power measurement system shall be in accordance with applicable test standards, i.e. IEC 62053-
22:2003 for power meters, IEC 61869-2:2012 for current transformers and
IEC 61869-3:2011/IEC 61869-5:2011 for voltage transformers. Equivalent test standards can also be adopted.
Type-test reports can be accepted as long as they demonstrate that the requirements in 3.1.6.3 (above) have been met.
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Overview of SS 591 : 2013
Section Three – clause 3.1.7 Data acquisition system
•
Provides the requirements of the data acquisition system
Measurement System Important clauses
The data acquisition system shall be able to record and store values up to at least 3 decimal places .
Data acquisition system
The memory space of the data acquisition system shall be sized for at least 36 months of storage capacity.
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Overview of SS 591 : 2013
Section Three –
•
Provides the minimum installation and set-up requirements for each measurement system
Flow meter Temp sensors
For magnetic flow meters
• Insertion types
• Installed in thermowells
• Test plugs before and after each temp sensor
Power meters
• Installed at the incoming side of the VSD
Wiring
• All measuring and control cables to have common screen
• Screens of control cables shall be connected to earthing points and from there, to the indoor earthing rings
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Overview of SS 591 : 2013
Section Four –
•
Provides the name architecture and naming rules for the data points monitored by the
BMS/EMS
Description
Chilled water flow rate
Chilled water system
Chilled water pump
Chilled water return temperature
Chilled water supply temperature
Chiller
Common header
Condenser pump
Condenser water flow rate
Condenser water return temperature
Condenser water supply temperature
Cooling tower
Heat Exchanger
Power
Primary chilled water pump
Secondary chilled water pump
Abbreviation
CHWF
CHWSYS
CHWP
CHWRT
CHWST
CH
HDR
CDWP
CDWF
CDWRT
CDWST
CT
HX
KW
PCHWP
SCHWP
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Overview of SS 591 : 2013
Section Four –
• Provides the list of data points to be trended in the BMS/EMS
Minimum Requirements
Clause 2.2: Data points
CHW and CW header return/supply temperature
CHW and CW header flow
Power input to groups of equipment (chillers,
CHW & CDW pumps, cooling towers)
Dry-bulb air temp and RH
Minimally 1 set along the cooling towers
Clause 2.3: Performance metrics
System cooling load
Supply chilled water temp
Temperature difference between chilled water supply and return
Heat rejected
Heat balance substantiating test
COP of chilled water system
Chilled water system energy efficiency
Equipment energy efficiency
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Overview of SS 591 : 2013
Section Four –
• Provides the requirements of the graphics display of the BMS/EMS
Minimum Requirements
• Sensor’s location and their dynamic values at 2 d.p.
•
Operating status of key equipment
•
Summary of set points
•
Instantaneous values of:
• Total cooling load and total condenser water tonnage
• Total power consumed by each group of equipment (chillers, CHW &CDW pumps and cooling towers)
•
System energy efficiency and COP
•
Equipment energy efficiency
• Instantaneous and cumulative values of total electrical energy consumed by the system
• System heat balance
Recommended Requirements
• Individual chiller energy efficiency
• Consistency checks (if instrumentation are installed at individual equipment level)
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Overview of SS 591 : 2013
Section Six –
•
Recommends the procedure that the owner can adopt in monitoring the performance and accuracy of the M&V system
Post-installation monitoring conducted through
BMS/EMS
Heat balance substantiating test
Multipoint consistency check
Use highly accurate portable instruments
In the event that any of the instruments does not tally with the verification instrument, it is recommended to replace or recalibrate the instrument.
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