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Low Carbon Economy, 2013, 4, 35-40
Published Online December 2013 (http://www.scirp.org/journal/lce)
http://dx.doi.org/10.4236/lce.2013.44A004
Open Access LCE
35
Carbon Dioxide Emissions from Thermal Power
Plants in Cameroon: A Case Study in Dibamba
Power Development Company
Jean Gaston Tamba1*, Francis Djanna Koffi1, Louis Monkam1, Simon Koumi Ngoh1,
Serge Nyobe Biobiongono2
1Department of Thermal and Energy Engineering, University Institute of Technology, University of Douala, Douala, Cameroon;
2Dibamba Power Development Company, Douala, Cameroon.
Email: *[email protected]
Received September 28th, 2013; revised October 25th, 2013; accepted November 1st, 2013
Copyright © 2013 Jean Gaston Tamba et al. This is an open access article distributed under the Creative Commons Attribution Li-
cense, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
ABSTRACT
This paper centres on the estimation of carbon dioxide emissions in a Cameroon thermal power plant called Dibamba
Power Development Company, in such a way that they can be included as part of Cameroon energy sector inventory or
used by the Dibamba Power Development Company to monitor its policy and technology improvements for mitigating
climate change. We have estimated the emissions using national emission factors for the consumption of liquid fossil
fuels and simulated a mitigation of these emissions till 2018 using alternative fossil fuels and carbon neutral model. The
results show that energy demand and carbon dioxide emissions in 2012 are estimated to be 48.964 ktoe and 164.39 kt
CO2 respectively. National emission factors for electricity generation are estimated to be 660.63 g/kWh. From 2012 to
2018, the thermal power plant will emit into the atmosphere 1298.42 kt CO2. These results also show that the use of
alternative fuels will reduce 59.22 kt CO2 per year for the same period while the use of the carbon neutral model will
reduce a total amount of 8.08 kt CO2. Finally, the total quantity of CO2 emission reduced for the period 2012 to 2018
will be 489.91 kt CO2.
Keywords: Assessment; Carbon Dioxide Emissions; DPDC; Cameroon
1. Introduction
The increase of greenhouse gases (GHG) emissions is an
important and most concerned issue. Human activities
are currently based on high consumption of fuels, and are
actually the major cause of GHG emissions, which can
undoubtedly be related with climatic changes [1]. There
are six greenhouse gasses (GHGs) with their respective
radiative forcing and global warming potential (GWP)
[2]. However, carbon dioxide (CO2) emissions are the
most important of the GHGs that are increasing in at-
mospheric concentration because of human activities [3].
Transportation, industrial and electricity production
(with fossil fuels combustion) are the main sectors iden-
tified to contribute to the emission of CO2 in Cameroon.
The electric power installed in Cameroon for the produc-
tion of electricity is 1593 MW and 18 percent of this
power is occupied by thermal power plants [4]. Currently,
in Cameroon, the issue of CO2 emissions in thermal
power plants is the focus of environmental policies of the
country. Note that Cameroon has a fleet of electricity
generation plants (thermal power) with a value of 285
MW which operates using fossil liquid fuels [4]. Among
the thermal power plants that have this park, the Di-
bamba Power Development Company (DPDC) is the
largest with 88 MW of installed power.
This paper estimates CO2 emissions in DPDC, com-
prising national emission factors for fossil liquid fuels
consumption [5,6]. CO2 emissions considered in this
study are from the fossil liquid fuels consumption needed
for electricity production. It is the emission from station-
ary combustion (thermoelectric power station) and mo-
bile combustion (vehicles) of the DPDC. The paper also
calculates the national emission factors for electricity
generation (kilogram CO2 per kilo watt hour) in 2012. In
*Corresponding author.
Carbon Dioxide Emissions from Thermal Power Plants in Cameroon:
A Case Study in Dibamba Power Development Company
36
addition, the paper shows a perspective mitigation of
CO2 emissions of DPDC from 2015 using the alternative
fossil fuels and the carbon neutral model.
The objectives of this paper are: 1) to show how the
CO2 emissions of thermal power plants can be estimated;
2) to improve on the second National Communication of
GHG emissions inventories of Cameroon to the United
Nations Framework Convention on Climate Change
(UNFCCC); 3) to permit future policies to deploy new
technologies with low carbon emission and consequently
reduce CO2 emissions for Cameroon’s thermal power
plants sector; 4) to permit DPDC to calculate CO2 emis-
sions using national emission factors.
The remainder of this paper is organised as follows:
we present an overview of DPDC in the next section.
Section 3 describes an overview of energy demand. Sec-
tion 4 presents an overview of the proposed methodology.
The results are reported in Section 5 and the last section
concludes the study.
2. Overview of DPDC
DPDC (Figure 1) is a mixed company specialised in
electric energy generation. It was created in 2011 and it
only uses power plants. DPDC is a subsidiary of AES-
Sonel (Apply Energizing Services-National Society of
electricity). It covers an area of 10 hectare (ha) with one
and 5 ha of lawn and grass respectively. In 2015, DPDC
will replace the 5 ha of grass with complex ecology. The
complex ecology is made of local trees and bushes.
AES-Sonel is the major shareholder with 56% stake and
the state of Cameroon with 44% [7]. DPDC is located in
the Littoral region of Cameroon, latitude 3˚59′ North and
9˚48′ East. It has eight identical thermoelectric power
stations brand Wartsila, an installed capacity of 11 MW
each [8]. Hence, DPDC is the largest thermal power plant
(88 MW) consuming fossil liquid fuels [4]. The ther-
moelectric power stations run only on heavy fuel oil
(HFO), while vehicles of the power plant run on gasoline
and diesel.
Figure 1. DPDC.
The running time of DPDC or Dibamba power plants
is not constant (Figure 2). On the AES-Sonel request,
Dibamba power plants come to reinforce the hydroelec-
tric plants to offset the energetic deficit. Figure 2 shows
that the working hour of thermoelectric power station of
DPDC is low (inferior to 200 hours) from June to No-
vember. This period corresponds to the Cameroon rainy
season [9]. March 2012 is the month during which the
power plant has turned more. Service hours represent the
working real time of thermal generator and period hours
the number of real hours in the month.
3. Overview of Energy Demand
3.1. Electricity Generation
On the request of AES-Sonel, DPDC sends 86 MW of
electric power to the national grid [7]. However, 2 MW
of electric power are used to supply the auxiliary power
plants. The monthly electricity generation is presented in
Figure 3. Gross generation is the total electricity genera-
tion (national grid and auxiliary power plants) in DPDC.
In 2012, DPDC generated 21.393 kilotons oil equivalent
(ktoe) (248,758 MWh) of electricity. From June to No-
Service Hours
Period Hours
800
700
600
500
400
300
200
100
0
Jan-12
Feb-12
Mar-12
Apr-12
May-12
Jun-12
Jul-12
Aug-12
Sep-12
Oct-12
Nov-12
Dec-12
Period
Hours
Figure 2. Service hours of Dibamba power plants from
January to December 2012.
Gross generation
HFO consumption
9000
8000
7000
6000
5000
4000
3000
2000
1000
0
Jan-12
Feb-12
Mar-12
Apr-12
May-12
Jun-12
Jul-12
Aug-12
Sep-12
Oct-12
Nov-12
Dec-12
Period
toe
Figure 3. Electricity generation and HFO consumption
from January to December 2012.
Open Access LCE
Carbon Dioxide Emissions from Thermal Power Plants in Cameroon:
A Case Study in Dibamba Power Development Company
37
vember, the electricity generation is weaker than the
other months. Hence, during this period AES-Sonel so-
licits more hydropower plants.
3.2. HFO Consumption
A thermal power plant needs fuel to generate electrical
energy. Thus, DPDC uses HFO to generate its electricity.
HFO consumption to produce electricity is responsible
for GHG emissions in general and CO2 in particular. As
for the case of electricity generation, Figure 3 shows the
monthly evolution of HFO consumption in 2012. We
also note that HFO consumption is lower from June to
November. So, DPDC used 48.939 k·toe (53,774 m3) of
HFO to generate electricity in 2012.
3.3. Gasoline and Diesel Consumption
Gasoline and diesel are used in vehicles. DPDC has six
(06) vehicles, with four (04) vehicles using diesel and
two (02) gasoline. The vehicles contribute to electricity
generation through transport of equipment and workers
of DPDC. Unlike Figures 2 and 3, Figure 4 clearly
shows that fossil liquid fuels (gasoline and diesel) con-
sumption is not influenced by climatic seasons. This con-
sumption can be influenced by the duration of mainte-
nance of the thermoelectric power station [10]. Diesel con-
sumption is more important than gasoline in 2012, about
21.114 tons oil equivalent (toe) (23.666 m3) for diesel
consumption against 4.489 toe (5.462 m3) for gasoline.
3.4. Future Demand of Fossil Fuels
Figure 5 shows the future demand of fossil fuels in
DPDC. This demand corresponds to the AES-Scenario.
This stipulates that fossil fuels demand in thermal power
plants increases by 4% from 2012 to 2018 in average [7].
Knowing that energy demand increases by about 8%
each year in Cameroon [4], 4% increase of fossil fuels
will contribute to satisfy energy demand and consequen-
gasoline consumption
diesel consumption
2.500
2.000
1.500
1.000
0.500
0.000
Jan-12
Feb-12
Mar-12
Apr-12
May-12
Jun-12
Jul-12
Aug-12
Sep-12
Oct-12
Nov-12
Dec-12
Period
toe
Figure 4. Gasoline and diesel consumption by vehicles from
January to December 2012.
diesel demand
gasoline demand
HFO demand
70,000
60,000
50,000
40,000
30,000
20,000
10,000
0
Period
toe
2012 2013 2014 2015 2016 2017 2018
Figure 5. Fossil fuels demand in AES-scenario.
tly increase the amount of CO2 in the atmosphere. Thus,
fossil fuels demand will increase by 12.991 k·toe (about
26.53%) from 2012 (48.964 k·toe) to 2018 (61.955·k·toe).
4. Methodology
In general, for each source sector or category, CO2 emis-
sions are calculated when the quantity of fuel consumed
at the national level of detail is multiplied by a specific
national emission factor [1,3,5,6,11-13]. CO2 emissions
in DPDC are estimated as follows:
,,2titiiiCO
i
EFCDLHVEF
(1)
where the subscript i represents the fuel type;
, the national emission factor of 2 of the th
fuel; i the national lower heating value on fuel
type and is the national density at 15˚C on fuel
type [5]. ,it
2iC
O
EF LH
i
i
CO i
V
i
D
F
C is fossil liquid fuels consumed on
fuel type in period . Fuel consumption is marked by a
meter and/or estimated by Equation (2) for thermoelec-
tric power stations, while it is estimated by Equation (3)
for vehicles [14].
t
tt
F
CHFOsales toDPDC (2)
,,titittt
i
F
CVVKTVORAF




(3)
where t
A
F
VOR
t
t
is the average number of kilometers trav-
elled for a vehicle per litre of fuel consumed each period
and is the vehicle occupancy rate for each
period . ,it represents the average annual vehi-
cle-kilometer travelled by a vehicle on fuel type in
period and ,it
V the number of vehicles on fuel type
in period t.
t
i
t
VKT i
After CO2 emissions calculation attributable to the
electricity generation in the DPDC, we calculate national
emission factors for electricity generation as follows:
t
tt
E
EF EG
(4)
Open Access LCE
Carbon Dioxide Emissions from Thermal Power Plants in Cameroon:
A Case Study in Dibamba Power Development Company
38
where represents the period, total CO2 emissions
and total electricity generation in DPDC.
t
EG E
DPDC plans to move to alternative fossil fuel as from
2015 (DPDC-Scenario). Applying the AES-Scenario,
DPDC will change HFO demand to natural gas inorder to
generate electricity from 2015 to 2018, which will reduce
the amount of CO2 emitted by DPDC into the atmosphere.
The calculation mechanism of CO2 emissions from the
natural gas consumption to generate electricity is as fol-
lows: we convert HFO demand to natural gas demand
from 2015 to 2018 [15,16] and then we apply Equation
(1). Thus, CO2 emissions that will be reduced by DPDC
are estimated by Equation (5):
,
tt
EEE
t
' (5)
where
R
E represents CO2 emissions reduced; the
total CO2 emissions (in the AES-Scenario), the total
CO2 emissions (in the DPDC-Scenario) and is from
2012 to 2018.
E
E
t
A regional carbon neutral model was built in this re-
search to assess total CO2 absorption by plants in DPDC.
The carbon neutral model structure is shown in [17]. The
total CO2 fixation volume calculation formula is dis-
played in Equations (6)-(8) [17,18].
2COi i
i
A
bsG A a




08 05..ra
(6)
 (7)

11 11
20 20
nnb nnb
ii ii
ii ii
raNt NbNt Nb

 

 
 (8)
where the 2CO
A
bs is the is the total CO2 absorption
volume of green areas; i
A
is the green area and i is
the CO2 fixation volume in unit area for the plant.
and t are the kinds and numbers of tree respectively.
and are the kinds and numbers of the original
trees in the country respectively. and are the
kinds and numbers of bushes respectively.
G
n
N
nNt
nb Nbnb
and
are the kinds and numbers of original bushes in the
country respectively. In this study, all plants used are
local. Thus, Equation (8) simplifies and is rewritten as
Equation (9).
Nb
1ra (9)
5. Results and Discussion
5.1. CO2 Emissions
Figure 6 presents the results of CO2 emissions in DPDC.
CO2 emissions are in the range of 1.945 - 28.399 kilotons
CO2 (kt CO2) for September and March respectively. We
note that CO2 emissions are lower (less to 10 kt CO2)
from June to November. These low CO2 emissions are
clearly justified by the service hours (Figure 2), energy
consumption (Figure 3) and Equation (1). So we con-
clude that electricity generation is less solicited during
this period. In 2012, DPDC rejects in the atmosphere
about 164.393 kt CO2, 13.699 kt CO2 per month aver-
agely. National emission factor (Figure 7) is in the range
of 653.48 - 667.87 g/kWh for February and March re-
spectively.
Contrary to Figure 6, Figure 7 clearly shows that na-
tional emission factor of CO2 is not influenced by cli-
matic seasons. In average, the national emission factor of
CO2 is about 660.63 g/kWh in 2012. When we analyze
emissions under AES-Scenario, the results show that
CO2 emissions in atmosphere are in the range 164.39 -
208.01 kt CO2 from 2012 to 2018 respectively, while
DPDC-Scenario shows that CO2 emissions are in the
range 164.39 - 145.26 kt CO2 from 2012 to 2018 respec-
tively (Figure 8). Note that from 2012 to 2018, the AES-
Scenario will emit in the atmosphere a total quantity of
1298.42 kt CO2 while if the DPDC-Scenario is applied,
the total quantity emitted will be 906.74 kt CO2.
5.2. Mitigation of CO2 Emissions
Figure 8 shows the amount of CO2 emissions that will be
reduced by alternating the HFO to natural gas by DPDC.
The application of DPDC-Scenario will reduce CO2
Jan-12
Feb- 12
Mar-12
Apr-12
May-12
Jun-12
Jul-12
Aug-12
Sep- 12
Oct-12
Nov-12
Dec-12
Period
30
25
20
15
10
5
0
ktCO
2
HFO CO
2
emissions gasoline CO
2
emissions diesel CO2 emissions
Figure 6. CO2 emissions in DPDC from January to Decem-
ber 2012.
Jan-12
Feb-12
Mar-12
Apr-12
May-12
Jun-12
Jul-12
Aug-12
Sep-12
Oct-12
Nov-12
Dec-12
Period
670.00
665.00
660.00
655.00
650.00
645.00
g/kWh
N
ational emission factor of CO
2
667.87 664.14
661.66
656.84
662.32
660.40
660.20
660.88
660.12
662.17
657.42
653.48
Figure 7. National emission factor for electricity generation
(g/kWh) of CO2 from January to December 2012.
Open Access LCE
Carbon Dioxide Emissions from Thermal Power Plants in Cameroon:
A Case Study in Dibamba Power Development Company
39
emissions in the atmosphere by 55.78, 58.02, 60.34 and
62.75 kt CO2 in 2015, 2016, 2017 and 2018 respectively.
Thus, 59.22 kt CO2 in average will be reduced per year
from 2012 to 2018 by DPDC.
Figure 9 presents the total mitigation of CO2 emis-
sions. Mitigation1 represents CO2 emissions reduction
with alternative fossil fuel, Mitigation 2 CO2 emissions
reduction with plant absorption and Mitigation 3 total
CO2 emissions reduction. CO2 absorption volumes of
green areas are in the range of 0.04 - 1.99 kt CO2 for
2012 and 2018 respectively. So plants will absorb 8.08 kt
CO2 from 2012 to 2018. Finally, applying DPDC-Sce-
nario and CO2 absorption by plants (complex ecology
and lawn), DPDC will reduce their CO2 emissions of
64.74 kt CO2 in 2018. Finally, the total amount of CO2
reduced for the period 2012 to 2018 will be of the order
of 489.91 kt.
5.3. Policy Implication
Although it is a Non-Annex 1 party, Cameroon became a
member of the United Nations Framework Convention
on Climate Change in 1994. Thus, it is committed with
the international community to help stabilize concentra-
tions of greenhouse gases (GHGs) in the atmosphere to
an extent that would prevent dangerous interference of
human activities with the climate system. Given the
Mitigation (kt CO
2
) AES-Scenario(kt CO
2
) DPDC-Scenario (kt CO
2
)
225
200
175
150
125
100
75
50
25
0
kt CO
2
Mitigation (kt CO
2
) 0 0 0 55.78 58.01 60.34 62.75
AES-Scenario(kt CO
2
) 164.39 170.97 177.81 184.92 192.32 200.01 208.01
DPDC-Scenario (kt CO
2
) 164.39 170.97 177.81 129.14 134.30 139.67 145.26
2012 2013 2014 2015 2016 2017 2018
Figure 8. Mitigation of CO2 emissions with alternative fossil
fuel.
80.00
60.00
40.00
20.00
0.00
kt CO2
2012 2013 2014 2015 2016 2017 2018
Mitigation1 (kt CO2) 55.78 58.01 60.34 62.75
Mitigation1 (kt CO2) 0.04 0.04 0.04 1.99 1.99 1.99 1.99
Mitigation1 (kt CO2) 0.04 0.04 0.04 57.77 60.00 62.32 64.74
2012 2013 2014 2015 2016 2017 2018
Figure 9. Total mitigation of CO2 emissions.
amount of CO2 emitted into the atmosphere by the DPDC,
mitigation policies must be taken for all thermal power
plants, preferably by considering the realities of Camer-
oon. As a Non-Annex 1 party, Cameroon’s government
has the right to insure favorable conditions to its devel-
opment, which inevitably requires the heavily investment
in the promotion of carbon reduction. Taxes on carbon
are not an important point for the Cameroon ministry of
environment. For Cameroon is considered as a Non-
Annex 1 party and its emissions are by far lower than
that of industrialized countries as well as the production
of electricity by thermal power plants in all other sectors.
Although there are several possible strategies to reduce
the amount of CO2 emitted from fossil fuel power plants,
Cameroon government suggests potential approaches that
include increasing plant efficiency, employing fuel bal-
ancing or fuel switching and rapid recovery of plants by
complex ecology plants, for all thermal power plants in
the country. The Cameroon ministry of environment sug-
gests to AES-Sonel concerning thermal power plants to
put in place an environmental policy in these power
plants. This policy includes planting one tree per em-
ployee for each AES-Sonel power plant per year. Thus,
the fixation volume by plants will increase and will thus
reduce the amount of CO2 emissions.
6. Conclusions
Energy demand and CO2 emissions by DPDC in 2012 are
estimated to be 48.964 k·toe and 164.39 kt CO2 respec-
tively. From 2012 to 2018, applying AES-Scenario will
emit into the atmosphere 1298.42 kt CO2. On the other
hand, applying DPDC-Scenario and carbon neutral
model by plants will reduce CO2 emissions by 489.91 kt
CO2 for the same period. With the above discussions, it
can be concluded that:
1) The study shows how the CO2 emissions of thermal
power plants are estimated.
2) The study also permits DPDC to calculate CO2
emissions using national emission factors.
3) The Cameroon government can use this study to
improve on the second National Communication of GHG
emissions inventories to the United Nations Framework
Convention on Climate Change.
4) Future environmental policies in Cameroon should
deploy new technologies, alternating fuels with liquid
fossil fuels and increase green areas around power plants,
and consequently reduce CO2 emissions for Cameroon’s
thermal power plants sector.
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Carbon Dioxide Emissions from Thermal Power Plants in Cameroon:
A Case Study in Dibamba Power Development Company
Open Access LCE
40
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