UNEP rise centre - Demark
Fourth regional workshop and training on
“Capacity development for the clean development mechanism”
4-6 April - AIT Thailand
Report, Case study 2
Study baseline methodology in Vietnam
comments and proposal
By Dr. Bui Huy Phung
Dr. Nguyen Tien Nguyen
VN CD for CDM
Key contents
Part I. Study to build the typical baseline for Vietnam
electrical grid
1.1. Methodology
1.2. Data needed
1.3. Result of typical baseline calculation for Vietnam
electricity grid
Part II. Comments and proposal.
2.1. Comments
2.2. Proposals used.
Part I. Study to build the typical baseline for
Vietnam electrical grid
1.1. Methodology
There are 2 specific guides issued by EB to calculate baseline
emission factor for the grid.
• Appendix B of the simplified modalities and procedures for
small-scale CDM project activities
• Consolidated baseline methodology for grid connected
electricity generation from renewable sources
Following quanlities must be calculated:
- The operating margin emission factor (EF-OM)
- The build margin emission factor (EFBM)
- The baseline emission factor EF.
1.1. Methodology (cont.)
a.
Based on guiders of appendix B, following calculation
formular are used
•
EF-OM (t CO2eq/kWh)= Ej/ Gj
Ej is CO2 emission per year in tons for fuel j- tCO2/year
Gj: electricity generation from fuel j
•
EF-BM (tCO2eq/kWh)= EFy.GENi /  GENi
EFi- the emission rate for unit i (tCO2/kWh)
GENi - the generation (kWh) from unit i.
•
Calculate 1/2(EFOM + EFBM)
•
Calculate GA-weighted average emission of all power
plants (grid average)
GA= Ej / GENj
1.1. Methodology (cont.)
b) Based on consolidated baseline methodology
• Calculate the operating margin emission factor (EFOMy)
+ Simple OM, EFOM simp. y - the generation weighted
average emission per electricity unit of all generating
sources serving in the system
EFOM,y=Fi,j y*COEFij / GENj,y
Fi,j,y- the mass of fuel i consumed by sources j in year y
+ Simple adjusted OM
In this case, power sources include imports and are
separated in low cost /must-run power plants.
b) Based on consolidated baseline methodology (cont.)
+ Dispatch data analysis OM
EFOM,Disp j = EOMy/EGy
In which
EGy - generation of project in year y (kWh, MWh)
EOMy = EGh*EFDDh
EGh - the generation in each hour h, and
EFDDh - the hourly generation weighted average emission per
electricity unit of the set of power plants (n) in the top 10% of grid
dispatch order during hour h.
+ Average OM aver
EFOM-aver is calculated as the average emission rate of all power
plants, using equation described for the simple OM above, but
including low-operating cost and must-run power plants.
1.1. Methodology (cont.)
c) The build margin emission factor
Calculate EFBM,y as the generation weighted average emission factor
of power plants (m)
EFBM , y   Fimj * COEFim /  GENm, y
im
m
d) Calculate the baseline emission factor EFy
EFy = WOMEFOMy + WBMEFBMy
When using this methodology there are a lot of difficulties
• It is short of day-night typical load diagram of grid in dry season and
rainy season, (or typical day of year) specially for future
• Dispatch data is not available so it can not to analyze OM
• It is complicated to identify low cost/must run power sources,
specially for future
• Etc.
So it is not able to calculate EFOM as requested conditions.
1.2. Needed key data
•
•
•
•
•
COEFj - CO2 emission per unite for each fuel j
LHVj - low heat value of fuel j
GENj - electricity generation from fuel j (kWh. MWh,…)
5 most recent plants and their performances
Or the most recent 20% of existing plants and their
performances
• Forecasted data of power plants and grid in study periods
• etc
1.3. Result of typical baseline calculation for Vietnam
electricity grid
a) Based on appendix B
Table 1: Baseline emission factors of the Vietnam national
grid, gCO2/kWh
End of
year
2001
2002
2003
GA
358.9
403.8
OM
884.7
BM
½ OM
+ ½ BM
2004
2005
2006
2007
2008
2009
2010
384.1 387.6
404.5 394.9
416.1
416.8
425.6
425.2
780.4
728.0 630.5
617.8 585.3
612.7
613.5
632.6
640.6
313.5
478.1
562.2 601.2
492.9 418.6
401.3
535.7
496.3
420.7
599.1
629.2
645.1 615.8
555.4 501.9
507.0
574.6
564.5
530.7
Figure 1. emission factors of the Vietnam national grid during
period of 2001-2010
900
800
gCO2/kWh
700
GA
OM
600
BM
½ OM+½ BM
500
400
300
2001
2002
2003
2004
2005 2006
Year
2007
2008
2009
2010
b) In case of consolidated baseline methodology
According to Simple OM
Table 2: Baseline emission factor calculated in OMsimple, gCO2/kWh
End of
year
Most
recent 3year
average
Commissioning
year
2001
-
2002
2003
2004
2005
2006
2007
2008
2009
2010
- 680.0 657.1 575.9 514.9 503.3 569.8 558.0 524.8
599.1 629.3 645.1 615.9 555.4 502.0 507.0 574.6 564.5 530.7
Figure 2: Baseline emission factor calculated in Simple OM
900
800
700
OM3year
gCO2/kWh
600
Omhd
500
BM
400
1/2OM3year+1/2BM
1/2OMhd+1/2BM
300
200
100
0
2001
2002
2003
2004
2005
2006
Year
2007
2008
2009
2010
Table 3: Baseline emission factor calculated in OMaverage,
gCO2/kWh
End of
year
Most
recent 3year
average
Commissioning
year
2001
-
2002
2003
2004
2005
2006
2007
2008
2009
2010
- 472.3 496.5 442.5 407.2 403.2 472.5 457.9 421.6
336.2 441.0 473.2 494.4 448.7 406.8 408.7 476.3 461.0 423.0
Figure 3: Baseline emission factor calculated in Average OM
650
600
gCO2/kWh
550
OM3year
OMhd
500
BM
1/2OM3year+1/2BM
450
1/2OMhd+1/2BM
400
350
300
2001
2002
2003
2004
2005
2006
Year
2007
2008
2009
2010
Part II. Comments and proposals
2.1. Comments
Based on using methodologies and calculation, we can conclude as
following:
– Two specific guiders issued by EB to calculate baseline emission factor
are interesting, conservative, that help developers to calculate baseline
in their condition.
– Baseline emission factors calculated in different options or
methodologies will be different. So depending on specific project,
applicable conditions, project developers can select an suitable
baseline emission factor.
In Vietnam case study :
– Emission factors of power plants using different fuels are different
+ Using coal coming down from 1.5 kgCO2/kWh to 1.0
kgCO2/kWh by 2010 year ;
+ Using oil is about 0.9 kgCO2/kWh ;
+ Using gas is about 0.45 kgCO2/kWh
– Average emission factor of system (1/2OM+1/2BM) having a
decreased trend and varying from 0.5 to 0.6 kgCO2/kWh.
2.1. Comments (cont.)
• Based on OM curves, it is seen that the baseline emission
factors decrease strongly because of increasing thermal
plants efficiency and more gas-fired plants built. But since
2006, mainly coal-fired plants will be built, so the factors
will be lightly increased.
• Since 2002, more thermal power plants are built, this is
described on the BM curves, but since 2006, hydropower
plants will be relatively large built, so the BM factor will
decrease.
• However, curves of average OM and BM as well as GA
curves are relatively stable.
2.2. Used proposals
a) Project registered in 2005, started operating in 2008, with
crediting of 10 years
• Small-scale project: select the table 1 above, at column of year
of 2005, can choose emission factors of ½ OM+ ½ BM (555.4
gCO2/kWh).
• Large scale project:
+ If total 5 years average hydropower output generated is less
than 50% of total electricity output generated of the grid, table
2 will be selected. Then there are 2 emission factors: if based on
the most recent statistics available at the time of Project Design
Document (PDD) submission then 3 years average emission
factor will be used, column of year of 2005 will be chosen (575.9
gCO2/kWh); if based on commissioning year then column of
year of 2008 will be chosen (574.6 gCO2/kWh).
2.2. Used proposals (cont.)
+ Or if total 5 years average hydropower output generated is more than
50% of total electricity output generated of the grid, table 3 will be
selected. Then there are 2 emission factors: if based on the most recent
statistics available at the time of PDD submission then 3 years average
emission factor will be used, column of year of 2005 will be chosen (442.5
gCO2/kWh); if based on commissioning year then column of year of
2008 will be chosen (476.3 gCO2/kWh).
This emission factor will used for project emission reduction calculation
for whole 10 year crediting period.
b) Project with crediting of 7 years registered in 2005, started operating in
2008: is similar to for crediting of 10 years above, the difference is the
emission factor only used in 7 years, if it is continued in more 7 years,
the emission factor will has to be re-calculated. Then the new factor may
be different from the old one because of data changes.
Thank you !
Contact address:
E-mail: phungbh@pmail.vnn.vn