Imran Khan1, Md Sahabuddin. 1. Department of Electrical and Electronic Engineering, Jashore University of Science and Technology, Jashore 7408, Bangladesh.
Abstract
In South Asian countries, the spread of COVID-19 was not treated seriously until mid-March 2020. Measures similar to those considered in Europe and other developed countries, such as maintaining social distance and lockdowns, were imposed. Lockdowns imposed a significant impact on the power sector, and this has been well explored in the literature for developed countries. A country-specific assessment of the impact of COVID-19 on the energy sector is crucial for future crisis management and underpinning sustainable power sector development plans. The impact of COVID-19 on Bangladesh's fossil-fuel dominated electricity sector is explored in this study. The analyses were conducted for 2019 and for the pandemic lockdown period in 2020. Daily hourly demand variations for different electricity generation zones in the country were investigated. The impact of these demand variations on greenhouse gas (GHG) emissions was assessed through time-varying carbon intensity analysis. Nationwide, the analysis revealed that the maximum hourly demand reduced by about 14% between 5 and 6 pm whereas the minimum demand reduction (3%-4%) occurred between 7:30 and 8 pm. Peak time demand reduction was found to be minimal during lockdowns. The national absolute GHG emission reduced by about 1075 kt CO2 e, an ∼16% reduction compared with that in 2019. Time-varying carbon intensity patterns varied significantly between zones.
In South Asian countries, the spread of COVID-19 was not treated seriously until mid-March 2020. Measures similar to those considered in Europe and other developed countries, such as maintaining social distance and lockdowns, were imposed. Lockdowns imposed a significant impact on the power sector, and this has been well explored in the literature for developed countries. A country-specific assessment of the impact of COVID-19 on the energy sector is crucial for future crisis management and underpinning sustainable power sector development plans. The impact of COVID-19 on Bangladesh's fossil-fuel dominated electricity sector is explored in this study. The analyses were conducted for 2019 and for the pandemic lockdown period in 2020. Daily hourly demand variations for different electricity generation zones in the country were investigated. The impact of these demand variations on greenhouse gas (GHG) emissions was assessed through time-varying carbon intensity analysis. Nationwide, the analysis revealed that the maximum hourly demand reduced by about 14% between 5 and 6 pm whereas the minimum demand reduction (3%-4%) occurred between 7:30 and 8 pm. Peak time demand reduction was found to be minimal during lockdowns. The national absolute GHG emission reduced by about 1075 kt CO2 e, an ∼16% reduction compared with that in 2019. Time-varying carbon intensity patterns varied significantly between zones.
carbon intensity at a particular time period tfuel specific emission factor for a particular GHGfuel specific emission for a particular GHG for a certain time period tfuel specific total carbon dioxide equivalent GHG emission at a particular time
period tfuel specific carbon dioxide equivalent emission for that particular GHG for a
certain time period ttotal carbon dioxide equivalent emissions from all fossil fuels and all GHGs at a
particular time period tfuel specific generation emission factor for a particular GHGfuel specific electricity generation in kWh for a time period tfuel specific electricity generation at a particular time period ttotal system generation from all fuels (including renewables and non-renewables) at
a particular time period tglobal warming potential of different GHGsfuel specific power plant’s efficiency
INTRODUCTION
Energy, particularly the use of electricity, is strongly related to the economic activity
of any country. However, due to the COVID-19 pandemic, there will be short- and long-term
impact on the electricity sector globally. For instance, the global electricity demand
decreased by about 15% due to the pandemic (Chiaramonti and
Maniatis, 2020). This impact included not only economic and energy-related issues
but also environmental factors such as greenhouse gas (GHG) emissions from electricity
generation (Khan, 2019d). For instance, the
International Energy Agency reported that primary energy demand and global energy-related
CO2 emissions reduced by 4% and 5.8%, respectively, in 2020; the CO2
emission reduction was 3.3% in the power sector in 2020 (IEA, 2021).Recent studies have focused on many different aspects of the COVID-19 pandemic and energy
systems. For example, a significant impact on energy demand was observed in China (Norouzi ., 2020). The impact on household energy use in China before, during, and
after lockdowns due to the COVID-19 pandemic was also explored (Cheshmehzangi, 2020). Another recent study investigated the overall
environmental impact of lockdowns, predominantly in the South Asia region (Arora ., 2020). The authors found a significant reduction in air and noise
pollution. However, the study did not pay particular attention to the electricity sector’s
impact on the environment. A similar environmental assessment was also conducted in China
(Wang and Su, 2020). The COVID-19 pandemic and its
impact on India’s economy were assessed by observing electricity consumption and nighttime
light intensity (Beyer ., 2021).Steffen (2020) analyzed the policy responses that should be
adopted to cope with the COVID-19 energy crisis, and the authors proposed three different
time horizons to tackle this kind of pandemic situation in the energy sector: short-, mid-,
and long-term plans. Short-term plans deal with immediate crisis response, mid-term plans
focus on economic recovery in the energy sector through new opportunities, and long-term
plans deal with making energy transitions a shock-proof sector through appropriate policy
development.One study reviewed the impact of COVID-19 from consumers’ point of view and critically
analyzed many different measures taken by governments around the world (Mastropietro ., 2020). For instance, the authors reported that “bill
reductions and cancellations” should not be provided to all consumers as it is an
inefficient approach. Similarly, a recent study reviewed the action plans of the G20 member
countries regarding electricity consumption during the pandemic (Qarnain ., 2020). For developing nations, such as African countries, preliminary responses to
the pandemic in the energy sector were short-term schemes, including free electricity, VAT
exemption, and waiving electricity bill payments (Akrofi and
Antwi, 2020). Similar initiatives were also undertaken by the Government of
Bangladesh. The government declared that “Household consumers will be able to pay
their delayed electricity bills for the months of February–June by July 31 without
fines” (Sajid, 2020a).To identify the electricity consumption gap due to the COVID-19 pandemic, a
prediction-based analysis method was proposed in Huang
. (2021). A study in
the USA found that “Energy sovereignty is a critical component in the design of a
post-COVID-19 energy system that is capable of being resilient to future shocks without
exacerbating injustices that are killing the most vulnerable among us” (Brosemer ., 2020). A data-driven analysis in the USA found that both power demand and
electricity prices were reduced during the pandemic (Ruan
., 2021). The
electricity generation from three major regional transmission organizations in the USA—the
New York ISO, the Pennsylvania–New Jersey–Maryland Interconnection, and the Midcontinent
ISO—was shifted from both base and peak load sources after the stay-at-home instructions
were issued (Eryilmaz ., 2020). Based on multivariate time series forecasting with
bidirectional long- and short-term memory, the influence of the COVID-19 pandemic on
electricity demand in the UK was investigated (Liu and Lin,
2021), and it was found that the electricity demand pattern followed the weekend’s
demand profile during the lockdown. Using data visualization and descriptive statistics, the
behavior of different European electricity systems including the German electricity system
during the pandemic was identified in Halbrügge . (2021).Closer to this study, Rugani and Caro (2020) assessed the impact of the COVID-19 pandemic on the
environment in Italy in terms of direct and indirect GHG emissions from electricity
consumption. The authors found that due to the lockdown, Italy was able to avoid 5.6 to 10.6
Mt CO2e for the period March–April 2020. Similarly, in ON,
Canada, there was a reduction of about 1267 GW (14%) of electricity demand due to the
pandemic in April 2020 (Abu-Rayash and Dincer, 2020).
Consequently, CO2e declined by 40 000 tonnes, which is a
positive impact on the environment for the same time period. In the USA, the electricity
demand reduction was about 10%, and as a result, CO2 emissions declined by 15%
for the lockdown period (Gillingham ., 2020).In the developing world, the impact of this pandemic is devastating and will hinder the
development for achieving sustainable development goals by 2030. Goal-7 is one of the
crucial sustainable development goals and is associated with “affordable and clean energy
for all,” and developing countries’ energy sector impact assessment is an utmost priority
for this pandemic situation. Immediate policy measures need to be initiated, as the one
identified in a recent study: “If sustainability is to be revived as a development
objective, then low and middle-income economies will need to come up with policies that
are affordable and achieve multiple SDGs simultaneously” (Barbier and Burgess, 2020). Hence, the objective of this study is to
analyze the impact of the COVID-19 pandemic on a fossil fuel-dominated electricity
generation system in a least developed country, Bangladesh.Previous studies have revealed electricity demand or consumption scenarios in developed
economies. For instance, the cumulative decrease in electricity consumption in the EU
countries and the states of the USA was between 3% and 12%, respectively, following the
stay-home orders for five months (Prol and O, 2020).
However, a recent review found that “fully enforced lockdowns and stay home orders
have increased the residential sector energy demand by a range from 11% to 32% for several
countries” (Krarti and Aldubyan, 2021).
The electricity demand reduced by about 20% in Italy and France (Chiaramonti and Maniatis, 2020). In Greece, the demand reduction was
about 1%–5%, whereas the change was minimal in Germany (EURELECTRIC, 2020). Electricity consumption in Austria and Denmark reduced within
the range of 10%–15% (EURELECTRIC, 2020). Energy
demand variations for different buildings such as residences, offices, and schools in a
district in Sweden were assessed through simulation to identify the impact of the COVID-19
crisis (Zhang ., 2020). In Spain, the consumption decreased by 13.49%
between 14 March and 30 April 2020, compared to the last five years’ average for the same
duration (Santiago ., 2021). In contrast, another study in Spain found that
residential consumers increased their consumption during the total lockdown and the
reopening period by about 15% and 7.5%, respectively (García
., 2021).The global reduction in consumption during the total lockdown by non-residential consumers
was about 38%, and during the reopening period, it was around 14.5% (García ., 2021). In Australia, the impact of lockdowns due to the COVID-19 pandemic on
energy use and peak demand in residential aged care (RAC) facilities was investigated, and
it was found that the energy use and peak demand reduction pattern depends on the
geographical location of the facility (Liu ., 2021). For instance, the
highest reduction in peak demand and energy use was observed in facilities that are in warm
regions.A recent study explored the spatial and temporal variations for different countries
dominated by developed ones and found that the variations were complicated (Jiang ., 2021). The same is true for a study in Lagos, Nigeria, in which the
authors considered three different scenarios—business-as-usual, partial lockdowns, and total
lockdowns—and assessed the changes in electricity demand and consumption (Edomah and Ndulue, 2020). However, the spatial and
temporal variations of electricity demand, generation, and environmental impact within a
developing country have not been explored well in the literature. The focus of this study is
twofold: first, to check the impact of lockdowns on electricity demand and generation for
Bangladesh and second, to check the consequences of this demand variation from an
environmental perspective, more specifically carbon emission intensity (in short, carbon
intensity).
Electricity system in Bangladesh
The electricity generation system in Bangladesh is dominated by fossil fuel generation.
According to the Bangladesh Power Development Board (BPDB) and the Sustainable and
Renewable Energy Development Authority (SREDA), fossil fuel and renewable generation
capacities are at about 20 548 MW and 647.49 MW, respectively (BPDB, 2020a and SREDA, 2020).
These capacities’ breakdowns are shown in Tables I
and II
TABLE I.
Fossil fueled and imported electricity generation capacity of Bangladesh [data
source: BPDB (2020a)] (HFO—heavy fuel oil and HSD— high-speed diesel).
Fuel type
Capacity (MW)
Coal
524
Gas
11 502
Oil (HFO and HSD)
7 362
Import from India
1 160
Total
20 548
TABLE II.
Renewable electricity generation capacity of Bangladesh [data source: SREDA (2020)].
On-grid
Off-grid
Total capacity
Fuel type
(MW)
(MW)
(MW)
Solar
87.05
326.51
413.56
Hydro
230
0
230
Wind
0.9
2
2.9
Biogas to electricity
0
0.63
0.63
Biomass to electricity
0
0.4
0.4
Total
317.95
329.54
647.49
Fossil fueled and imported electricity generation capacity of Bangladesh [data
source: BPDB (2020a)] (HFO—heavy fuel oil and HSD— high-speed diesel).Renewable electricity generation capacity of Bangladesh [data source: SREDA (2020)].The BPDB has divided the country into nine electricity generation zones, as illustrated
in Fig. 1. These generation zones include both
renewable and non-renewable sources. For instance, 230 MW hydro and 27 MW solar
generations (from power plants) are included in the Chattogram zone. The other solar
generations were from 3 MW to 8 MW solar power plants in the Mymensingh and Rangpur zones.
Although the Dhaka zone has the highest generation capacity (6119 MW), the actual derated
capacity is 5895 MW. The derated capacities for Chattogram, Cumilla, Mymensingh, Sylhet,
Khulna, Rajshahi, and Rangpur were found to be 2266, 2980, 637, 1988, 2284, 3668, and
605 MW, respectively. In terms of energy trading, 160 and 1000 MW electricity was imported
from India through Cumilla and Khulna zones, respectively.
FIG. 1.
Zone-specific installed generation capacities in MW (as of 6 August 2020) [data
source: BPDB (2020b)].
Zone-specific installed generation capacities in MW (as of 6 August 2020) [data
source: BPDB (2020b)].The total retail electricity consumption in Bangladesh was 63 364 GWh in the financial
year 2019–2020, of which the dominant sector was residential, with a share of 57.02%,
followed by industrial (27.58%), commercial (10.19%), and agriculture (2.42%); the rest
were other sectors (2.79%) (BPDB, 2020c).According to the BPDB’s annual report (BPDB,
2019), there are two types of power plant owners in Bangladesh: government and
private. The power plants in the private sector are mainly gas- and oil-fired, and the
efficiencies of these plants vary over a wide range. For example, the lowest efficiency
for gas- and oil-based power plants were found to be 27.25 and 32.5, respectively. The
highest efficiencies were 49.06 and 44.97, respectively. This is depicted in Fig. 2(a)
FIG. 2.
Box and whisker plot showing (a) private- and (b) government-owned power plants’
efficiencies in Bangladesh. The horizontal line and cross indicate the median and
average value for that fuel type within each box, respectively. The lower (and upper)
edges of the box are the 25th (75th) percentile. Whiskers represent the upper and
lower ranges, and the dots represent the outliers [data source: BPDB (2019) and EQMS (2015)].
Box and whisker plot showing (a) private- and (b) government-owned power plants’
efficiencies in Bangladesh. The horizontal line and cross indicate the median and
average value for that fuel type within each box, respectively. The lower (and upper)
edges of the box are the 25th (75th) percentile. Whiskers represent the upper and
lower ranges, and the dots represent the outliers [data source: BPDB (2019) and EQMS (2015)].The lowest efficiencies of the government-owned power plants were found to be 19.28,
16.14, and 19.36 for gas-, oil-, and coal-fueled plants, whereas the maximum efficiencies
were 56.13, 42.74, and 44.49 for the same types of plants, respectively. This is shown in
Fig. 2(b). For the government-owned power plants,
zone-specific average plant efficiencies varied between 30.27 and 40.80 for gas-fired ones
and 19.81 and 40.32 for oil-fired ones. The average efficiency of the gas-fired power
plants in the Cumilla zone was found to be higher than that in the other zones. For the
oil-fired plants, the efficiency was found to be comparatively better in the Dhaka zone
than in the others. Overall, the private sector’s power plant efficiencies were found to
be better than those of the government-owned power plants in Bangladesh.The rest of the article is organized as follows: Sec. II explains the data and method used for the analysis. Section III presents the results and related analysis. Section
IV discusses the findings, and the final section
concludes the article.
DATA AND METHOD
For this analysis, daily, hourly, and half-hourly electricity generation data were
collected from the Bangladesh Power Development Board (BPDB) and the Power Grid Company of
Bangladesh (PGCB) websites (PGCB, 2020 and BPDB, 2020d). Data were considered from the end of March
to the end of May of 2019 and 2020 so that a comparison of the lockdown and the baseline
situation can be made. Many recent studies also considered these two consecutive years for
this type of analysis; for example, see Mastropietro
(2020) and Abu-Rayash and Dincer (2020).The time-varying carbon intensity approach is chosen for emission analysis as it is able to
investigate a number of factors at one time, such as identifying temporal carbon intensity
variation, determining peak carbon-intensive (carbon peak) hours, and identifying the
dominant fuel contributing to emission reduction or acceleration; for further details, see
Khan (2019d)
and Khan (2018). Previous studies considered average efficiencies
of different electricity generation technologies, whereas in this study, plant-specific
efficiencies were used. Thus, this analysis provides more accurate emission data from
individual power plants in Bangladesh. Greenhouse gas emissions and time-varying carbon
intensities were calculated using the following formulas [adopted from Khan (2018) and Khan (2019d)]:Here,
GWP = 1 for
CO2, 25 for CH4, and 298
for N2O,For emission calculation, three major
GHGs—carbon dioxide (CO2), methane (CH4), and nitrous oxide
(N2O)—were considered for this analysis. As no national GHG inventory is
available in Bangladesh, to calculate
GEF, the
fuel-specific emission factor for a particular fuel was considered from the
Intergovernmental Panel on Climate Change (IPCC), Fourth Assessment Report (AR4) (IPCC, 2007). Although the IPCC Fifth Assessment Report
(AR5) was available, the AR4 was used for this analysis so that the results can be compared
with those of the previous literature for Bangladesh (Khan,
2018). These emission factors are listed in Table
III. The coal used for electricity generation in Bangladesh is mainly
sub-bituminous coal, and the characteristics of heavy fuel oil (HFO) and high-speed diesel
(HSD) oils are in the distillate fuel oil No. 2 category; hence, these were considered for
emission factor selection (cf. Table III). While life
cycle emissions were present from renewable sources such as hydro and solar, they were
assumed to be emission-free due to their insignificant contribution compared to fossil-fuel
emissions. Fuel specific power plant efficiencies were taken into account from the BPDB
annual report and the environmental impact assessment (EIA) report of specific power plants
(cf. Fig. 2) (BPDB, 2019 and EQMS, 2015).
TABLE III.
Fuel-specific emission factors [adopted from IPCC (2007)] (note: 1 mm BTU = 293.07
kWh).
kgCO2 per
gCH4 per
gN2O per
Fuel
mm BTU
mm BTU
mm BTU
Sub-bituminous coal
97.17
11.00
1.60
Natural gas
53.06
1.00
0.10
Distillate fuel oil No. 2 (used for HFO and HSD)
73.96
3.00
0.60
Fuel-specific emission factors [adopted from IPCC (2007)] (note: 1 mm BTU = 293.07
kWh).
RESULTS AND ANALYSIS
The analysis was conducted according to the BPDB generation zones. Diverse changes in
electricity demand and emissions were observed in these zones.Electricity daily demand variations at different zones in Bangladesh before, during,
and after the lockdown period (for interpretation of the references to color in this
figure legend, the reader is referred to the Web version of this article).(a) Zonal emission for the lockdown period (23 March–30 May) in 2020 and emission in
2019 for the same period, (b) the box and whisker plot showing the percentage of
emission reduction in 2020 compared with 2019 during the lockdown period in Bangladesh
for eight different zones (Barisal was excluded as emission increased during the same
period). The horizontal line and cross indicate the median and average value of carbon
intensities within each box, respectively. The lower (and upper) edges of the box are
the 25th (75th) percentile. Whiskers represent the upper and lower ranges.
Electricity demand variations
To check the demand variations, three different weeks from three different months were
taken into account during the lockdown period: 26 March–1 April, 16–22 April, and 21–27
May 2020. The same calendar days were also considered from 2019 for comparison purposes.
Unfortunately, for 26 and 27 May 2019, demand data were missing in the online database;
thus, demand data of 19–25 May 2019 were used for comparison. These daily demand
variations are plotted in Fig. 3
FIG. 3.
Electricity daily demand variations at different zones in Bangladesh before, during,
and after the lockdown period (for interpretation of the references to color in this
figure legend, the reader is referred to the Web version of this article).
During 26 March–1 April, the daily electricity demand in the Dhaka zone reduced
significantly from the range 3000–4000 MW in 2019 to 2300–2800 MW in 2020. For the other
zones, demand reduction was insignificant. Interestingly, the demand fluctuations on
weekdays and weekends were completely absent during the lockdown period in 2020.For the week 16–22 April 2020, the Dhaka zone’s demand reduced further and reached below
2500 MW. The demand in Chattogram was below 1000 MW in 2020, which was above 1000 MW in
the previous year for the same calendar days. The demand also reduced for Cumilla. For the
other zones, changes in demands were marginal. Nevertheless, daily demand fluctuations
were found in this week during the lockdown period, perhaps due to residential demand
variations.Compared to the period April 21–27 May 2020, the demand in the Dhaka zone increased and
varied between 2500 MW and 3000 MW, while that in Chattogram remained below 1000 MW for
this week as well. For the Khulna zone, electricity demand reduced in 2020 compared to the
demand in 2019 during the same week. For instance, the maximum demand was found to be
1508 MW in 2019 but was 1133 MW in 2020. Although fluctuations in demand were found for
other zones in 2020, the demand range did not reduce significantly.Before and after the lockdown, the Dhaka zone’s demand varied between 3003 and 3752 MW,
whereas this variation was between 2354 and 2705 MW during the lockdown. Similarly, for
Chattogram, the demand variations before and after lockdown were 991–1180 MW and
870–1059 MW, respectively; during the lockdown, this variation was between 821 and
1068 MW. Overall, substantial changes in electricity demand during the lockdown period
were observed predominantly for Dhaka and Chattogram.Note that as the comparisons were made during the same time period for both years, the
impact of weather was not considered. However, it can be seen that the electricity demands
in all the zones were higher in June than in March due to the increased temperature and
humidity for the latter month (cf. Fig. 3).
Carbon intensity variations
In terms of absolute emission, the analysis revealed that due to the lockdown, a decline
of 1075 kt CO2e of GHG emissions was recorded compared to the
previous year. Thus, a 16% emission reduction was observed compared with the previous year
for the same time period. Zone-specific absolute emissions between the previous and this
year show that emissions were reduced for every zone except Barisal. This is depicted in
Fig. 4(a)
FIG. 4.
(a) Zonal emission for the lockdown period (23 March–30 May) in 2020 and emission in
2019 for the same period, (b) the box and whisker plot showing the percentage of
emission reduction in 2020 compared with 2019 during the lockdown period in Bangladesh
for eight different zones (Barisal was excluded as emission increased during the same
period). The horizontal line and cross indicate the median and average value of carbon
intensities within each box, respectively. The lower (and upper) edges of the box are
the 25th (75th) percentile. Whiskers represent the upper and lower ranges.
Emission reduction was observed in different zones, ranging from 9% to 33% [see Fig. 4(b)]. The average reduction percentage was found to
be 17%. The highest reduction in GHG emission was found for the Dhaka zone, followed by
Chattogram, Rajshahi, and Cumilla, and the minimum reduction was found for Rangpur.
Barisal’s emission increased from 232 kt CO2e in 2019 to 520
kt CO2e in 2020, which is about a 124% increase. This is due
to the fact that a coal-fired power plant with a present capacity of 622 MW (which will be
expanded to 1320 MW) came online in January 2020. Although it uses ultra-supercritical
power generating units, emissions increased more than double the figure for the previous
year.The time-varying carbon intensity analysis for different zones provided detailed insights
into the emission patterns on an hourly basis, and this varied substantially from one zone
to another. For example, drastic changes in hourly emissions were observed for Barisal due
to the addition of a coal-fired power plant in the generation fleet. Notably, the
emissions at peak hours during the lockdown increased more than threefold compared to
those in 2019 (see Fig. 5).
FIG. 5.
Box and whisker plot showing carbon intensity variations in Bangladesh for Barisal,
Chattogram, Cumilla, and Dhaka between 23 March and 30 May for 2019 and 2020. The
horizontal line and cross indicate the median and average value of carbon intensities
within each box, respectively. The lower (and upper) edges of the box arethe 25th
(75th) percentile. Whiskers represent the upper and lower ranges, and the dots
represent the outliers. Note: The lockdown period due to the COVID-19 pandemicwas from
23 March to 30 May 2020 in Bangladesh (for interpretation of the references to color
in this figure legend, the reader is referred to the Web version of this article).
Box and whisker plot showing carbon intensity variations in Bangladesh for Barisal,
Chattogram, Cumilla, and Dhaka between 23 March and 30 May for 2019 and 2020. The
horizontal line and cross indicate the median and average value of carbon intensities
within each box, respectively. The lower (and upper) edges of the box arethe 25th
(75th) percentile. Whiskers represent the upper and lower ranges, and the dots
represent the outliers. Note: The lockdown period due to the COVID-19 pandemicwas from
23 March to 30 May 2020 in Bangladesh (for interpretation of the references to color
in this figure legend, the reader is referred to the Web version of this article).For Chattogram, the 24 h carbon intensity (CI) in 2019 was found to be almost flat, and
the average hourly CI range was between 53 and 60 gCO2e/kWh.
In contrast, the average hourly CI was found to be in the range 41–55
gCO2e/kWh during the lockdown period in 2020. Importantly,
noticeable fluctuations were observed for the 24 h carbon intensity profiles, and the
evening peak is clearly visible (see Fig. 5). The
reason might be that residential electricity usage, as all other industrial and commercial
activities, was suspended for the lockdown period.In Cumilla, the carbon intensity varied between 38 and 95
gCO2e/kWh in 2019. In 2020, during the lockdown period, this
range varied between 45 and 87 gCO2e/kWh. Noticeable
reductions in carbon intensity were observed from 1 to 6 pm; CI reduced during the
afternoon hours in Cumilla. The average CI was between 60 and 70
gCO2e/kWh for both years.A dramatic reduction in CI was observed for Dhaka during the lockdown in 2020. For
instance, the average hourly CI varied between 145 and 159
gCO2e/kWh in 2019. Contrarily, this range was 115–122
gCO2e/kWh during the lockdown in 2020. During the
non-pandemic period, there were two CI peaks in Dhaka—one at 3 pm and another at 8 pm.
Nevertheless, during the lockdown period, CI was almost flat all through the day (see
Fig. 5).During the non-pandemic situation in 2019, the lowest average CI (13.42
gCO2e/kWh) was found at 9 am, and the highest average was
35.81 gCO2e/kWh at 8 pm in Khulna. A sharp increase in CI can
be seen during peak hours (5–11 pm) in 2019. One of the reasons for this sharp increase is
that most of the power plants in this zone are oil-fired and serve as peaking power
plants. Notably, oil is more carbon-intensive than natural gas. For the lockdown period in
2020, from 1 am to 6 pm, the average hourly CI became almost flat and varied between 20.72
and 23.82 gCO2e/kWh, whereas during peak hours, this range
increased to 22–32 gCO2e/kWh. For both years, the whiskers and
outliers represent the peaking power plants’ activity-related emissions (see Fig. 6).
FIG. 6.
Box and whisker plot showing carbon intensity variations in Bangladesh for Khulna,
Mymensingh, Rajshahi, and Rangpur between 23 March and 30 May for 2019 and 2020. The
horizontal line and cross indicate the median and average value of carbon intensities
within each box, respectively. The lower (and upper) edges of the box are the 25th
(75th) percentile. Whiskers represent the upper and lower ranges, and the dots
represent the outliers. Note: The lockdown period due to the COVID-19 pandemic was
from 23 March to 30 May 2020 in Bangladesh (for interpretation of the references to
color in this figure legend, the reader is referred to the Web version of this
article).
Box and whisker plot showing carbon intensity variations in Bangladesh for Khulna,
Mymensingh, Rajshahi, and Rangpur between 23 March and 30 May for 2019 and 2020. The
horizontal line and cross indicate the median and average value of carbon intensities
within each box, respectively. The lower (and upper) edges of the box are the 25th
(75th) percentile. Whiskers represent the upper and lower ranges, and the dots
represent the outliers. Note: The lockdown period due to the COVID-19 pandemic was
from 23 March to 30 May 2020 in Bangladesh (for interpretation of the references to
color in this figure legend, the reader is referred to the Web version of this
article).In Mymensingh, the hourly CI change during the lockdown in 2020 was marginal compared to
2019. For example, a noticeable change was only observed between 5 and 7 am. Similarly,
the hourly CI reduced from midnight to early morning for the Rajshahi zone during the
lockdown in 2020 compared with 2019. Although the CI pattern in 2020 was almost identical
to that in 2019 in Rangpur, hourly CI fluctuations were evident. For example, at 6 am, the
CI fluctuated between 31.32 (25th percentile) and 46.79
gCO2e/kWh (75th percentile) in 2019, whereas this variation
was 27.84–57.70 gCO2e/kWh in 2020 during the lockdown period.
Interestingly, a carbon-intensive peak was observed in the morning for this zone (see
Fig. 6).It can be seen from Fig. 7 that Sylhet has a morning
carbon peak (“carbon peak” and “carbon intensity peak” are used interchangeably in the
text) during non-pandemic hours in 2019. In contrast to most other zones, Sylhet showed a
drop in carbon intensity during evening peak hours. In 2020, the morning peak shifted to
11 am and created a day carbon peak because of the impact of lockdowns. On the other hand,
an evening drop in carbon intensity was not found during the lockdown (see Fig. 7).
FIG. 7.
Box and whisker plot showing carbon intensity variations in Bangladesh for Sylhet and
National between 23 March and 30 May for 2019 and 2020. The horizontal line and cross
indicate the median and average value of carbon intensities within each box,
respectively. The lower (and upper) edges of the box are the 25th (75th) percentile.
Whiskers represent the upper and lower ranges, and the dots represent the outliers.
Note: The lockdown period due to the COVID-19 pandemic was from 23 March to 30 May
2020 in Bangladesh (for interpretation of the references to color in this figure
legend, the reader is referred to the Web version of this article).
Box and whisker plot showing carbon intensity variations in Bangladesh for Sylhet and
National between 23 March and 30 May for 2019 and 2020. The horizontal line and cross
indicate the median and average value of carbon intensities within each box,
respectively. The lower (and upper) edges of the box are the 25th (75th) percentile.
Whiskers represent the upper and lower ranges, and the dots represent the outliers.
Note: The lockdown period due to the COVID-19 pandemic was from 23 March to 30 May
2020 in Bangladesh (for interpretation of the references to color in this figure
legend, the reader is referred to the Web version of this article).The national average hourly CI varied between 496 and 530
gCO2e/kWh in 2019. A clear carbon peak was also present at
8 pm. For the lockdown period in 2020, the average hourly CI range was found to be 488–514
gCO2e/kWh, with a similar carbon peak in the evening.
Although hourly CI fluctuations were observed all day, the maximum fluctuations were found
during the middle of the day (see Fig. 7).In summary, time-varying carbon intensity analysis revealed the hourly emission status
for different zones in Bangladesh. Of the nine zones, Cumilla and Dhaka had day
carbon-intensive peaks; Barisal, Chattogram, Khulna, and Rajshahi had carbon-intensive
peaks in the evening. Mymensingh has a midnight carbon peak whereas Rangpur and Sylhet
showed carbon-intensive peaks in the morning for the non-pandemic period. During the
lockdown in 2020, there was no day carbon-intensive peak found for Cumilla. Late night and
afternoon carbon peaks were observed for Dhaka. No evening carbon peak was found for
Barisal.On the other hand, Chattogram, Khulna, Mymensingh, and Rajshahi had a peak in the
evening. An early morning carbon peak was found for Rangpur. Interestingly, Sylhet’s
morning carbon peak shifted from 7 to 11 am as a day peak. In terms of national carbon
intensity, the overall pattern was identical to that of the non-lockdown situation.
However, CI reduced during the lockdown. At the same time, hourly fluctuations increased
during the lockdown period.
DISCUSSION
It is evident from the analysis results that daily demand variations for most of the zones
in Bangladesh are not significant. For instance, a dramatic decrease in daily demand was
found for Dhaka, whereas for many other zones such as Barisal and Sylhet, this reduction was
marginal. Importantly, these zonal demand variations altogether have an impact on the
national demand profile. For example, the average half-hourly demand profiles for three
weeks—from 1 to 21 April for both 2019 and 2020—are plotted in Fig. 8, along with their changes.
FIG. 8.
Three weeks’ averaged demand profiles for April in 2019 (solid line) and 2020 (dotted
line) and change (%) in demand between these two years (for interpretation of the
references to color in this figure legend, the reader is referred to the Web version of
this article).
Three weeks’ averaged demand profiles for April in 2019 (solid line) and 2020 (dotted
line) and change (%) in demand between these two years (for interpretation of the
references to color in this figure legend, the reader is referred to the Web version of
this article).Electricity demand reduced for the lockdown period in 2020 compared to 2019. The maximum
reduction was about 14% in the afternoon, predominantly between 5 and 6 pm (see Fig. 8). On the other hand, during evening peak hours, this
reduction was within the range of 3%–5%. During the day peak hours, the demand reduction was
4%–8%. Peak demand reduction due to the COVID-19 pandemic and the lockdown was also reported
in ON, Canada (Abu-Rayash and Dincer, 2020). A similar
situation was also observed in NY, USA (Chen ., 2020).In the industrial and commercial sectors, electricity consumption dropped by about 50% and
40%, respectively, due to this pandemic, whereas consumption increased by about 15% in the
residential sector (FE, 2020). More than half
(57.02%) of the electricity demand in Bangladesh is from the residential sector (BPDB, 2020c). This also justifies the minimum demand
reduction during the network peak hours in Bangladesh. Domestic electricity consumption or
demand also increased in other countries during the lockdown, and it ranges from 11% to 32%
(Krarti and Aldubyan, 2021). For example, in
Bulgaria, domestic electricity consumption increased by 1.18% (EURELECTRIC, 2020). In Spain, residential consumers increased their
consumption by 15% during the lockdown (García ., 2021).To cross-check with individual daily average hourly demand profiles, four days were
randomly selected during the lockdown time in 2020 and compared with the same calendar days’
demand in 2019. These demand profiles are illustrated in Fig.
9. It can be seen that at the beginning of the lockdown, that is, the last week of
March 2020, the demand reduction was not significant. Later, in April and May, the national
daily demand reduction was noticeable.
FIG. 9.
Four different days’ demand profiles during the lockdown period in 2020 compared with
the same calendar days’ demand in 2019 (for interpretation of the references to color in
this figure legend, the reader is referred to the Web version of this article).
Four different days’ demand profiles during the lockdown period in 2020 compared with
the same calendar days’ demand in 2019 (for interpretation of the references to color in
this figure legend, the reader is referred to the Web version of this article).Electricity demand variations were reported in many recent studies, predominantly for the
developed world. For example, about 12%, 20%, and 25% demand reductions were found in the
UK, France, and Italy, respectively (Energy World,
2020). Gillingham
(2020) reported a 10% demand reduction in the USA.
Similarly, there was a reduction of 14% of electricity demand due to this pandemic in ON,
Canada (Abu-Rayash and Dincer, 2020). On the other
hand, in developing countries such as India and Nepal, demand reductions were 19%–40% (Aruga ., 2020 and Aggarwal, 2020) and 21%–28%
(Nepali Times, 2020 and Bhushal, 2020), respectively.Electricity consumption was 12 950 GWh in 2019, but this reduced to 11 098 GWh in 2020
during Bangladesh’s lockdown period, an ∼14% reduction. Similar reductions were also
observed in many other countries; for example, about 10%–15% electricity consumption
reduction occurred in Austria and Denmark during the lockdown period (EURELECTRIC, 2020). Electricity demand and consumption-related changes
during the lockdown in many European countries can be found in EURELECTRIC (2020).The analysis also explored the carbon intensity levels of nine different electricity
generation zones in Bangladesh. In 2019, the most carbon-intensive zone was Dhaka as the
average hourly CI range was found to be 145–159 gCO2e/kWh,
followed by Sylhet (67–83 gCO2e/kWh), Cumilla (63–67
gCO2e/kWh), and Rajshahi (59–67
gCO2e/kWh). In contrast, the lowest carbon intensive zone was
found to be Barisal (hourly average: 14–21 gCO2e/kWh), followed
by Mymensingh (hourly average: 16–24 gCO2e/kWh). However, the
hourly CI fluctuations were higher for Mymensingh than for Barisal.Although the CI reduced for the Dhaka zone during the lockdown, it remains the most
carbon-intensive zone. A recent study also found overall emission reduction in Dhaka due to
the lockdown (Arora ., 2020). For all other zones, the hourly average CI reduced,
except Barisal, where a new coal-fired power plant came online in January 2020 with
ultra-supercritical technology for emission control. However, the CI level increased
significantly in this zone, a two-to three-fold increase in hourly average CI (42–50
gCO2e/kWh). The overall change in CI patterns for the nine
zones and the national pattern is summarized in Table
IV
TABLE IV.
Carbon intensity changes in different zones with and without the lockdown.
No pandemic, no lockdown
COVID-19 pandemic and
Zone
year: 2019
lockdown year: 2020
Barisal
Minor carbon peak in the evening.
The overall pattern has not changed, but hourly carbon
intensity fluctuation increased significantly due to the addition of a coal-fired
power plant.
Chattogram
Almost a flat carbon intensity pattern with a minor
evening carbon peak.
Hourly CI fluctuations with a clearly visible evening
carbon peak.
Cumilla
Almost a flat carbon intensity pattern with a minor day
carbon peak.
Almost a flat carbon intensity pattern with no carbon
peak.
Dhaka
Two clear carbon peaks: One at about 3 pm in the afternoon
and another in the evening at 8 pm.
Two minor carbon peaks: One in the early morning and
another in the afternoon.
Khulna
One clear evening carbon peak.
One clear evening carbon peak and hourly CI fluctuations
were reduced.
Mymensingh
A midnight carbon peak and hourly CI fluctuations all
through the day.
Morning and evening carbon peaks with hourly CI
fluctuations all through the day.
Rajshahi
An evening peak and hourly CI fluctuations all through the
day.
Two carbon peaks: One during the day and another in the
evening with hourly CI fluctuations
Rangpur
One morning carbon peak.
One morning carbon peak and hourly CI fluctuations all
through the day.
Sylhet
One morning peak and an evening “carbon valley.”
One day peak.
National
A clear carbon peak in the evening.
A clear carbon peak in the evening and hourly CI
fluctuations all through the day.
Carbon intensity changes in different zones with and without the lockdown.This coronavirus pandemic and the worldwide economic shocks are forcing governments
worldwide, including Bangladesh, to assess the resilience of the power sector. Due to this
crisis, it is expected that there would be a severe impact on the energy sector. For
example, in terms of economic evaluation, the estimated loss in Bangladesh’s power sector
due to the pandemic from March to December 2020 is expected to be BDT [Bangladeshi taka
(Bangladeshi currency)] 354.07 × 109, and the breakdowns are shown in Fig. 10. About half of the total loss was from the
distribution sector, which is about BDT 176.66 × 109, followed by a tariff
deficit.
FIG. 10.
Power sector’s estimated loss from different sub-sectors due to the COVID-19 pandemic
from March–December 2020 in Bangladesh [date source: Sajid (2020b)].
Power sector’s estimated loss from different sub-sectors due to the COVID-19 pandemic
from March–December 2020 in Bangladesh [date source: Sajid (2020b)].This analysis provides several insights into a fossil fuel-dominated electricity system.
First, the COVID-19 pandemic reduced emission levels from electricity generation compared to
the same period in the previous year. However, this type of reduction is due to crisis
management-related energy use and on a very short-term basis. Although this may be true, it
shows how far it is possible to control emissions from a fossil-fueled electricity
generation system by suspending all types of industrial and commercial activities. This
might help set targets for the electricity sector’s emission control to achieve sustainable
development goal-7 (UN, 2015).Second, the electricity demand reduced due to the shutdown of many industrial and
commercial activities. Correspondingly, consumption at residences increased, and the
electricity sector of Bangladesh was dominated by the residential consumer. To reduce
electricity demand along with emissions on a long-term basis, separate initiatives should
thus be considered. For instance, demand-side management (DSM) in every sector (e.g.,
residential and commercial) could be a valuable option for achieving this aim.Third, Bangladesh’s electricity generation expansion plan is dominated by fossil fuels
(Khan, 2018), and very few options are available to
integrate renewable sources due to resource unavailability. Thus, to reduce demand along
with DSM schemes, efficiency improvement in home appliances might be an effective option as
more than 50% of consumers are from residences.Fourth, this analysis used actual power plant-specific efficiency for generation emission
factor calculations. Thus, it provides more accurate carbon intensity levels for a zone and
the country. For example, in several previous studies, average efficiency was considered for
different types of power plants in Bangladesh, and they found that the hourly average CI
varied between 660 and 685 gCO2e/kWh for the year 2015 (Khan, 2018). Another study found that “the median daily
time-varying carbon intensity fluctuated between 647 and 695 gCO2-e/kWh”
across all seasons in Bangladesh in 2015 (Khan,
2019d). In contrast, this analysis revealed that national carbon intensity variations
were 496-530 gCO2e/kWh in 2019 but 488–514
gCO2e/kWh in 2020 during the lockdown period. This implies
that the use of actual efficiencies for individual power plants provides more accurate
carbon intensity measures for a country.Apart from these, there is a huge challenge after the pandemic: plastic waste management,
mainly plastic used for personal protection items in the medical sector. One of the very
common practices in managing this waste is the waste-to-energy conversion through
incineration, and most of the developed nations would be following this practice. Although
these plastic wastes have worthwhile calorific value for electricity generation, they emit
GHGs (Klemeš ., 2020).Based on the results obtained here, it is clear that even with the country-wide closure of
industrial and commercial activities for more than two months, the reduction in GHGs from
the electricity sector is not significant (16% only), compared to the previous year. This
indicates that to reduce GHG emissions from a fossil fuel electricity sector such as
Bangladesh to ensure sustainable development, several policies need to be implemented. These
policies could also be adopted by countries with similar electricity systems and where the
integration of new renewable sources is not feasible due to resource limitations. Overall,
if demand can be reduced, related GHG emissions from this fossil fuel sector can also be
minimized.
CONCLUSION AND POLICY IMPLICATIONS
Globally, the COVID-19 pandemic has affected the power sector in many ways. For instance,
demand was reduced, triggering unprecedented instability in energy markets. This can be seen
from recent oil price falls in the international market. However, in some countries,
residential electricity consumption increased. On the other hand, as demand decreased, GHG
emissions also declined in a fossil fuel-dominated electricity sector, and consequently,
environmental pollution was reduced.Notably, the pandemic hindered global economic growth as electrical energy is the driving
force for this growth, predominantly in emerging economies, and Bangladesh is no exception.
Similar to many other emerging economies, Bangladesh’s electricity sector has also been
affected by the pandemic. This study’s objective was to assess the impact of the pandemic on
the electricity sector of Bangladesh, which has a fossil fuel-dominated electricity
generation system. The findings from this study could also be applied to countries with
similar electricity generation systems.The analysis revealed that during the country-wide lockdown, electricity demand varied from
one zone to another. Significant demand reduction was observed for Dhaka and Chattogram
during the lockdown period compared to other zones. For other zones, the daily demand
variations were marginal. In terms of national hourly demand variation, the maximum and
minimum demand reductions were found in the afternoon (5–6 pm) and evening (7–8 pm), network
peak hours.Carbon intensity also varied from one zone to another. For absolute zonal emission, the
maximum emission reduction was found for Dhaka (33.81%) followed by Chattogram (28.81%),
with a minimum in Rangpur of 9.72%. Notably, emissions increased by 124% in Barisal due to
the addition of a new coal-fired power plant in this zone. Time-varying carbon intensity
also varied from one zone to another. Due to the lockdown, carbon peaks also shifted from
one hour to another. For example, a morning carbon peak in Sylhet moved to 11 am and became
a day carbon peak.This study provided detailed insights into Bangladesh’s electricity sector changes due to
the COVID-19 crisis and recommended policy implications toward sustainable development in
the energy sector. The study also has a few limitations. First, this analysis has not
considered indirect emissions from renewable sources such as the life cycle emissions from
solar and hydropower plants. Second, the oil-fired power plants in Bangladesh use high-speed
diesel (HSD) and heavy fuel oil (HFO) as their primary fuels. However, the emission factor
was considered for distillate fuel oil No. 2, which has similar characteristics to HSD and
HFO but is not the same. Thus, the carbon intensity for the oil-fired power plant might vary
slightly from the results obtained.Similarly, the emission factor for sub-bituminous coal was taken into account for this
analysis for the new coal-fired power plant in Barisal. Predominantly, this coal is imported
from different countries such as Indonesia and Australia, and based on the coal quality, the
emission factor might vary marginally. Although true, the carbon intensity variations due to
marginal emission factor changes would be insignificant. Apart from this, the imported
electricity from India was not considered for the analysis.Based on this analysis, the following policy implications could be applicable for the
developing world with fossil fuel dominated electricity systems:Effective DSM schemes at residences need to be deployed for electricity demand
reduction. Previous studies have found that different DSM schemes need to be employed
at different stages. For instance, energy-saving behaviors could be an effective
primary method that could effectively reduce residential demand by about 21.9% (Khan, 2019a). The next DSM scheme after
energy-saving behavior could be technology involvement in DSM. However, to manage
residential demand effectively with technology, the factors that dominate electricity
demand at residences (Khan, 2019b) need to be
identified through appropriate methods (Khan
., 2019).Efficiency improvement in electrical appliances is another means of reducing
electricity demand, not only for the industrial and commercial sectors but also in the
domestic sector. However, such an improvement does not have a substantial impact on
peak demand reduction (Borg and Kelly, 2011).
One study found that home appliances' efficiency improvement could reduce energy
consumption by about 11%–38% (Khan, 2019a).More renewable generation options for the electricity generation system need to be
explored. For example, Bangladesh does not have many other renewable generation
options, except solar. However, due to the scarcity of land, it is difficult to
achieve a substantial effect through solar generation in the country. There are also
other options that require further research, which could be used as potential
renewable sources to generate electricity, such as waste to energy schemes (Khan and Kabir, 2020 and Khan, 2019c).Cross-border electricity trading might be another option to reduce demand in a fossil
fuel-dominated electricity generation system, along with the security of supply (Kumar Singh, 2013). For instance, Bhutan, Nepal,
and India have a total estimated capacity of 263 GW hydropower potential (Khan, 2020a). If these renewable energy potentials
can be utilized through cross-border energy trading, a large amount of GHGs from the
electricity sectors of Bangladesh and India could be saved. At the same time, this
would underpin economic growth and other benefits in this region (Alam ., 2019).As Bangladesh is a least developed country, research in the energy management and
sustainability field is limited due to many constraints, such as inadequate funding.
Thus, a lot of research needs to be conducted to identify potential solutions that
could help reduce emissions from the electricity sector. One such area could be
waste-to-green hydrogen generation and its application in the electricity generation
sector (Khan, 2020b).