Additional information on calculating the grid emission factor of Lao PDR for the JCM
Summary
It is concluded that net emission reductions are achieved by applying the following emission
factors to 3 cases in Lao PDR.
・ Table 1 summarizes the applied reference emission factors for the PV system(s) in a
proposed project activity, which is directly connected to the Lao Power Grid, orconnected to the grid via an internal grid not connecting to a captive power generator(PV Case 1).
・ Table 1 also summarizes the applied reference emission factors for the PV system(s) in a
proposed project activity, which is connected to an internal grid connecting to both theLao Power Grid and a captive power generator (PV Case 2).
・ A reference emission factor of 0.533 t-CO2/MWh is applied, in the case that the PVsystem (s) in a proposed project activity is only connected to an internal grid connecting
to a captive power generator (PV Case 3).
Table 1. Reference emission factor PV Case 1, Case 2 and Case 3
Emission factor for
PV Case 1(t-CO2/MWh)

Emission factor for
PV Case 2(t-CO2/MWh)

Emission factor for
PV Case 3(t-CO2/MWh)

0.319

0.319

0.533

1. Current status of electric power source mix in Lao PDR
The Lao Power Grid, consists of the connected Northern grid, Central 1 grid, Central 2 grid,and Southern grid (Figure 1). The Electricite Du Laos (EDL), a state company, carries out
generation, transmission, distribution, supply and commercialization of electric energy.

1Figure 1. Map of electricity system in Lao PDR1

The Lao Power Grid is directly connected with the Thailand, Vietnam, and China Power
Grids. According to the document published by Ministry of Natural Resources andEnvironment (MONRE) Lao PDR2, the connected Lao Power Grid and Thailand Power Grid
(hereafter referred to as “Lao-Thailand Power Grid”) is defined as the interconnected
electricity system for which Lao grid emission factor was calculated. Electricity generation in
the Lao-Thailand Power Grid is provided in Table 1.

Table 1. Electricity generation in Lao-Thailand Power Grid
Electricity source (GWh)
Coal2012

2013

2014

2015

2016

32,53433,38735,71232,78135,3030000.40

204

Thailand grid

32,53433,38735,71232,78035,099Oil

Thailand grid

2,068

1,787

1,896

1,320

1,075

Gas

Thailand grid

117,063

117,005

118,559

126,985

124,761

13,747

12,492

13,032

10,174

10,875

Lao grid

Renewable energies

1Approximate figure based on Electricite du Laos, Electricity Statistics 2016
MONRE (2014). Calculation for the emission factor for electricity generation in Lao PDR, 2010 (established for theCDM).
22

Lao grid (hydro)

2,642

3,708

3,886

4,210

6,735

11,105

8,784

9,145

7,955

8,233

149

246

274

302

158

Viet Nam

36

27

35

48

43

China

113

219

239

254

115

165,413

164,671

169,199

171,259

172,014

71%

71%

70%

74%

73%

Thailand grid (hydro, solar,wind, biomass, others)
ImportTotal excluding import% Generation from natural gas

Sources: Electricite du Laos, Electricity Statistics 2016; Electricity Generating Authority of Thailand, Annual Report
2013; Annual Report 2014; Annual Report 2016.

2. Calculation of emission factor of the Lao-Thailand Power Grid
Natural gas-fired power plants hold the majority in overall power supply to theLao-Thailand Power Grid, with an absolute amount increasing during 2005 to 20133, andstaying at around 70-74% in the last three years (Table 1).

Electricity Generation in Lao-Thai Power Grid (GWh)

117,063

117,005

118,559

126,985

124,761

32,53433,38735,71232,78135,303

2012

2013

2014

2015

2016

ImportRenewable energies (hydro, solar, wind power, biomass, others)
Gas
Oil
Coal

3

Organization for Economic Co-operation and Development (OECD), Energy Statistics of Non-OECD Countries 2015,
August 2015.

3

Figure 2. Trend of electricity generation sources in Lao-Thailand Power Grid
Therefore, emission from natural gas power plants, which also has the lowest emission
factor among fossil fuels, is used to calculate the reference emission factor of theLao-Thailand Power Grid in a conservative and simple manner to secure net emission
reduction.

The CO2 emission factor of power generation by natural gas-fired power plants is calculated from theplant efficiency using the following equation:
CO2 emission factor of power generation [tCO2/MWh] (equation1)= CO2 emission factor of natural gas [tCO2/TJ] *0.0036 [TJ/MWh] / (Thermal efficiency(Lower Heating Value: LHV) [%] / 100)

Applying the CO2 emission factor of natural gas combustion, which is 54.3 tCO2/TJ derived
from “IPCC guideline 2006, Chapter 2, stationary combustion” together with the thermal
efficiency (LHV) of 61.2% to the equation 1, the emission factor of power generation by themost efficient natural gas-fired power plant is calculated to be 0.319 t-CO2/MWh.
Table 2. Constants for calculation of reference emission factor
Item

ValuesReference

Best thermal efficiency of naturalgas

powerplant(Khanom 61.2%4

Mitsubishi Heavy Industry5

Electricity Generating Co., Ltd.)Best thermal efficiency of dieselpower plant

JCM Approved
Methodologies: PW_AM001,MN_AM003, etc.

49%

CO2 emission factor of natural gas 54.3 tCO2/TJ

IPCC guideline for National

CO2 emission factor of diesel

Greenhouse Gas Inventories

72.6 tCO2/TJ

2006, Chapter 2, stationary
combustion6
The lower value is applied.

4

Since auxiliary power consumption is unknown, the plant efficiency of gross electricity generation is applied. This ensuresthe calculation of a conservative emission factor.
5
https://www.mhi-global.com/news/story/1308201706.html
https://www.mhps.com/en/products/thermal_power_plant/gas_turbin/lineup/m701f.html
6 IPCC default values at the lower limit of the uncertainty at a 95 per cent confidence interval

43. Calculation of the emission factor of a captive power generator
To determine the emission factor of a captive power generator which normally uses a diesel
generator in a conservative and simple manner, the thermal efficiency of 49%, an efficiency
level which has not been achieved yet by the world’s leading diesel generator, is applied.

The emission factor of diesel power generation is calculated from the thermal efficiency
using the following equation:

Emission factor of diesel power plant [t-CO2/MWh] (equation 2)= (Emission factor of diesel [tCO2/TJ] *0.0036[TJ/MWh]) / (Thermal efficiency (Lower Heating
Value: LHV) [%]/100)

Applying the default value of the emission factor of diesel combustion which is 72.6 tCO2/TJ
derived from “IPCC guideline 2006, Chapter 2, stationary combustion”, together with thethermal efficiency of 49% to the equation 2, the emission factor for a captive power generator(EFRE,cap) is calculated to be 0.533 tCO2/MWh.

5