Additional Information
on Default Values

1Default values for boilers and chillers for the reference emission calculation

For projects introducing high efficiency boilers and heat recovery heat pumps, the methodology
requires efficiencies of existing boilers and chillers at a project site for the calculation of thereference emissions.
Under the usual practice, efficiencies of boilers and chillers gradually deteriorate over the years
even with regular maintenance, which leads to increase in BaU emissions.
HighHigh

Efficiencies

BaU emissions
Low

Low
time

Figure 1: Image of a relationship between efficiencies and GHG emissions in themethodology
As per the JCM guideline 1, JCM methodologies need to establish conservative default
efficiencies in order to ensure net emission reductions.
1) Default values for boiler efficiencies:
Default efficiencies for new boilers listed in a methodological tool 2 of the CDM are considered
to be conservative compared with those of old boilers, and thus the values for new boilers areadopted (see Table 1). These values will be updated along with the revision of the CDM tool.
Table 1: Default efficiencies for new boilers in the CDM methodological tool (ver. 01.0) 2
Technology of the energy generation system

Default efficiency

New natural gas fired boiler (w/o condenser)

92%

New oil fired boiler90%

New coal fired boiler

85%

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2

“Joint Crediting Mechanism Guidelines for Developing Proposed Methodology” (JCM_VN_GL_PM_ver01.0)
Tool to determine the baseline efficiency of thermal or electric energy generation systems

22) Default values for chiller efficiencies:
In 2012 and in 2013, Hibiya Engineering Ltd. conducted energy audit for 15 four-star andfive-star hotels in Ho Chi Minh City (HCMC) and Hanoi. Names of chiller manufacturers at the15 hotels are listed in Table 2.
Table 2: Names of chiller manufacturers at 15 hotels
Chiller manufacturers

AB

CHanoi

263HCMC12

1Total

384% share

20%

53%

27%

Interviews taken from facility managers and construction companies during the energy audit
revealed that Vietnamese chiller market is dominated by three manufacturers, Carrier, Trane,and York. In addition to the three manufacturers, because its name was mentioned during theinterviews and showed presence as efficient chiller brand in the Vietnamese market, Daikin isalso included in the determination of default chiller efficiency.
For commercial buildings including hotels, the chiller capacity is in general less than 500RT in
Viet Nam. Chiller efficiencies change over size of the cooling capacity; therefore, it isappropriate to establish the default chiller efficiencies by the range of cooling capacity.
In the SI metric system, Coefficient of Performance (COP) is used to measure chiller
efficiencies. The higher the number in COP, the more efficient the chiller is. Table 3 shows
COPs for different cooling capacity ranges by different manufacturers at the similar standard
temperature condition. The COP information was retrieved from catalogues collected inVietnam in June 2014 without any consideration of their market share, therefore, including highefficiency models.

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Table 3: chiller COPs by cooling capacity and manufacturers*
Manufacturer

Cooling capacity(USRT)

COP

A

209

6.04

D207

5.86

C200

5.38

A

295

5.95

D300

5.97

C300

5.55

D449

5.97

B450

6.181273732

C450

5.63

1273732

Chilled watertemperature

Condenser watertemperature

730

12.5

735.3

30

7127303732

730*Additional information was collected, where possible, to fill in blanks that could not be found in the catalogues.

Table 4 shows an average between maximum and minimum COPs in each range of cooling
capacity. They are tentatively considered as default chiller efficiencies.
Table 4: Default chiller efficiency
Cooling Capacity/unit

200 USRT class

300USRT class450USRT class(range of USRT)(x≦250)(250＜x≦300)(300＜x≦500)

COP

5.71

5.75

5.913) Conservativeness check: comparison of default chiller efficiencies against existingchillers
Efficiency of existing chillers in various hotels in Vietnam was surveyed in July 2014, and theresult is summarized in Table 5.
Table 5: Efficiency of existing chillers at hotels in Vietnam
Default

Conservativeness

COPcheck

5.37

5.71

483

4.13

5.91

C253

4.99

5.75

Hotel D

B

383

4.14

5.75

Hotel E

B300

5.28

5.75

○○○○
○

Hotel

Manufacturer

USRT

COP

Hotel A

B

167

Hotel B

B

Hotel C4Hotel FHotel GA500

5.02

5.91

A250

4.88

5.71

○
○150

4.06

5.71

○150

4.40

5.71

○

Othermanufacturer
B

The hotel that has the latest model among the surveyed targets was Hotel A, where the chiller
was installed in December 2012 and its efficiency was COP 5.37. As shown in Table 5, none of
the surveyed chillers exceeded the default chiller efficiencies in Table 4, even the most recently
introduced chiller.
This survey result suggests that the application of the default chiller efficiencies of Table 4 inreference emission calculations leads to more conservative reference emissions than that ofexisting chiller efficiencies.
Thus, the default efficiency values applied in this methodology are the ones shown in Table 4.

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