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American Journal of  
Environment and Climate (AJEC)

Entity-level Greenhouse Gas Emission of  University of  Science and 
Technology of  Southern Philippines-Oroquieta

Mitchie Roa1* 

Volume 1 Issue 3, Year 2022
ISSN: 2832-403X (Online)

DOI: https://doi.org/10.54536/ajec.v1i3.665
https://journals.e-palli.com/home/index.php/ajec

Article Information ABSTRACT

Received: October 12, 2022
Accepted: October 15, 2022
Published: October 17, 2022

Presently, climate change is still one of  the pressing environmental concerns in the world 
generally caused by greenhouse gas emission. Among the greenhouse gases emitted by 
various sources, carbon dioxide contributes largely to the emission. In this study, the entity-
level greenhouse gas emission of  the University of  Science and Technology of  Southern 
Philippines-Oroquieta for Year 2020 was estimated following the 2006 IPCC Guidelines 
for National Greenhouse Gas Inventories. Based on the results, emission from mobile 
combustion sources was estimated to be 0.0895 tCO2e while emission from stationary 
combustion sources was 0.139 tCO2e yielding a total GHG emission for Scope 1 of  0.2285 
tCO2e. Moreover, the electricity consumption of  the campus which corresponds to the 
Scope 2 emission yielded 24.7135 tCO2 constitutes largely to the overall greenhouse gas 
emission. This might be due to the flexible learning modality where faculty members stay at 
their respective offices to conduct their classes hence regularly utilizing electricity from air 
conditioners, computers, mobile phones and others.

Keywords
Carbon Dioxide Emission, Entity-
Level Greenhouse Gas Emission, 
Greenhouse Gas Accounting

1 University of  Science and Technology of  Southern Philippines-Oroquieta, Philippines
* Corresponding author’s e-mail: mitchie.roa@ustp.edu.ph

INTRODUCTION
The issue about the global climate change caused 
by greenhouse gases was recognized in 1970s but 
international initiatives started in 1990s. Since then, the 
primary goal of  global researches focused on reducing 
emission sources and enhancing carbon sinks to combat 
greenhouse gas emission (Montagnini & Nair, 2004). 
Some of  these include innovative engine and vehicle 
technologies to reduce fuel consumption (Shaheen & 
Lipman, 2007), tree planting, maintaining and restoring 
forest ecosystems (Domke et al., 2020), and ratification of  
global climate agreements such as the UNFCCC (United 
Nations Framework Convention on Climate Change), 
Kyoto Protocol and, the most significant to date, Paris 
Agreement (Maizland, 2021). 
The Paris Agreement which entered into force last 
November 2016 aims to limit the increase in global 
temperature below 2 degrees Celsius by strengthening 
global response, which includes climate change adaptation 
and mitigation, to the threats and impacts of  climate 
change (UNFCCC, 2020; Zhao et al., 2018). 
The University of  Science and Technology of  Southern 
Philippines (USTP)-Oroquieta is one of  the satellite 
campuses of  the USTP system. It is located at Mobod, 
Oroquieta City in the Province of  Misamis Occidental 
which geographically lies within latitude 8°29’ north and 
longitude 123°47” east (USTP-Oroquieta, n.d.). 
An initiative of  USTP-Oroquieta relevant to becoming 
a carbon-neutral campus has been conducted by select 
faculty members engaged in science-related profession 
to quantify and consequently suggest campus policies 
for low carbon emission through estimating the entity-
level greenhouse gas (GHG) emission which results from 
the operations of  the campus following the 2006 IPCC 
Guidelines for National GHG Inventory Accounting 

methodology. 
As of  2020, there has been a significant decrease or 
interruption on the usual activities or operations in the 
campus brought about by the COVID-19 pandemic, 
hence, the results of  this accounting might serve as a 
baseline data for future studies. The GHG accounting was 
created to monitor the direct and indirect GHG emissions 
of  USTP-Oroquieta. This can also be considered as the 
initial step to planning the activities and programs that 
the campus could implement to mitigate GHG emission. 
Furthermore, it seeks to meet the following objectives:

• Identify the sources of  GHG emissions from the 
operations of  USTP-Oroquieta;

• Quantify the amount of  GHG emissions from 
identified activity sources; and

• Determine appropriate projects and activities that 
would reduce the campus’ GHG emission.

LITERATURE REVIEW
Climate change occurs because of  natural and 
anthropogenic activities, and the main contributors to 
this are the greenhouse gases (Yue & Gao, 2018). These 
gases are naturally present in the earth’s atmosphere, 
hence making the planet warm. Without these, the world 
would be as cold, or even colder, as ice (Ma, 1998). These 
can be emitted naturally by volcanic eruptions, ocean 
currents, solar radiations, and earth orbital changes, 
however excessive emission has been observed through 
the years because of  human activities (Nunez, 2019). 

Global Greenhouse Gas Emission
The World Resources Institute (WRI) reported that the 
global annual greenhouse gas emissions have increased 
to 48.94 MtCO2e since 1990 with the energy sector as 
the biggest source contributing 76% of  the emission 

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worldwide in 2018. At the same period, similar trend was 
observed in the Philippines which had approximately 
136.60 MtCO2e increase in GHG emissions from 1990-
2018. Approximately 59% of  the total emission was 
contributed by the energy sector with a whopping 138.51 
MtCO2e in 2018 followed by the agriculture sector with 
26.14% (Climate Watch, n.d.). 
Carbon dioxide is one of  the key greenhouse gases 
emitted to the atmosphere through burning of  fossil fuels, 
solid wastes and biomass (US EPA, 2020). It can also be 
emitted from direct human-induced impacts on forestry 
and other land use changes such as deforestation, grazing 
and degradation of  soil, which dramatically elevated since 
the start of  the industrial revolution (Arneth et al., 2019). 
In the latest record of  the World Resources Institute 
Climate Analysis Indicator Tool (WRI CAIT), the global 
total CO2 emission excluding the land-use change and 
forestry (LUCF) in 2018 was 35.25 GtCO2 while the total 
CH4, N2O and fluorinated gas (F-gas) only contributed 
8.18 GtCO2e, 2.99 GtCO2e and 1.14GtCO2e, respectively 
(Climatewatch, n.d.). 
Over the past decades, carbon dioxide emission was already 
increasing every year by about 1%; however, the impact 
of  the COVID-19 pandemic in 2020 led to the drastic 
change in emission (Friedlingstein et al., 2019; Jackson et 
al., 2019; Peters et al., 2020). Quéré et al. (2020) cited that 
although there is a decrease in global CO2 emission in 2020 
due to the reduced activity of  the people and businesses 
during the pandemic as the world governments enforced 
stringent measures to lessen and stop the transmission of  
the virus, this is not enough to combat climate change. 
Although the COVID-19 pandemic struck every country 
and continues to immobilize and limit various sectors 
from emitting CO2, researchers found that this is far from 
achieving net zero emissions due to the lack of  enactment 
of  “green” recovery policies. This decrease in emission 
is even just temporary as the adaptation and recovery 
measures of  the government permits to continue people 
and business activities. 

Entity-level Greenhouse Gas Emission
Generally, there are two types of  reporting greenhouse 
gas emission, mainly the entity-level and community-level. 
Both types include three scope emissions, and the present 
study only applied the entity-level GHG accounting. Here, 
Scope 1 refers to the direct GHG emissions contributed 
by mobile and stationary combustion sources, Scope 2 
refers to the indirect GHG emissions from the purchase 
of  electricity, and Scope 3 refers to all the other indirect 
emissions such as domestic air travels, employee 
commuter travel, waste disposal and others (IPCC, 2014).

Carbon Dioxide Emission in the Philippines
The Philippines is known to have a very small carbon 
footprint; however, it is one of  the countries that is most 
vulnerable to the impacts of  climate change which slow 
down its economic development (Tribe, 2018; Durana, 
2017). In 2020, Philippines had a carbon dioxide emission 

of  136.02 MtCO2 while other developing countries such 
as Pakistan, Vietnam, Thailand and Malaysia have emitted 
234.75 MtCO2, 254.30 MtCO2, 257.77 MtCO2, and 
272.61 MtCO2, respectively (Ritchie & Roser, 2020). In 
the succeeding year, the country ranked 17th among all 
of  the countries with the highest risks and most affected 
by extreme weather conditions according to the Global 
Climate Risk Index (Congressional Policy and Budget 
Research Department, 2021). The country experienced 
calamities and is in fact highly prone to natural disasters 
especially sea-level rise, coastal flooding, typhoons, 
earthquakes and volcanic eruptions (World Bank, 2005; 
Bollettino et al., 2020). Other climate change impacts 
observed in the Philippines which generally resulted from 
the increase in global atmospheric carbon dioxide were 
experienced such as temperature rise, decreased regularity 
of  precipitation, decreased quantity of  surface water due 
to higher air temperatures, and northward shift of  marine 
species due to increased temperature in the ocean (Tribe, 
2018).

MATERIALS AND METHODS
Research Setting
The accounting estimates the entity-level GHG emissions 
from the operations of  USTP-Oroquieta which cover 
the buildings and facilities in the campus for Year 
2020 following the 2006 IPCC Guidelines for National 
Inventories methodology. The GHG emissions to be 
accounted for were determined through the boundary 
conditions, mainly the “organizational boundaries” which 
refer to the facilities owned or controlled by the campus 
and “operational boundaries” which refer to the types of  
emissions included or excluded from various emission 
sources. 
Generally, USTP-Oroquieta consists of  the Administration 
Building, IT Building, Dressmaking Building and Canteen; 
the canteen however stopped operating since the pandemic 
started because there was no longer face-to-face classes. 
Presently, the campus owned a car which has never been 
used and a motorcycle used for errands. Most of  the fuel 
consumption for Year 2020 therefore came from the 
usage of  the campus-owned motorcycle, rented vans for 
research and training purposes, and rented equipment for 
landscaping and construction of  the makeshift classrooms. 
Moreover, the operational boundary categorizes emissions 
resulting from facilities and activities of  USTP-Oroquieta 
classified as direct and indirect emissions and further into 
scopes as presented in Table 1. 
Here, each emission sources are further classified 
according to scope and category. Scope 1 refers to direct 
GHG emissions from sources owned and controlled by 
USTP-Oroquieta such as the motorcycles and rented vans 
for official travel and errands, Scope 2 refers to indirect 
emissions from the purchase of  electricity and Scope 3 
are for all other indirect GHG emissions that occur as 
consequence of  the activities and operations of  the campus. 
Fugitive emissions from the use of  fluorinated gases in 
refrigeration and air-conditioning equipment, emissions 

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Table 1: Direct and Indirect Emission of  USTP-Oroquieta
Operational Boundary
Classification Scope Category Included/ Excluded Reason for Exclusion
Direct Emissions 1 Mobile Combustion Included

Stationary Combustion Included
Fugitive Emission Excluded Data not available

Indirect Emission 2 Purchased Electricity Included
3 Air Business Travel Excluded No air travel made

Transmission and 
Distribution Loss

Excluded Data not available

Employee Commute Excluded No employee commute made
Solid Waste Disposal Excluded Data not available

from transmission and distribution loss and emissions 
from solid waste disposal are excluded due to unavailability 
of  data. Furthermore, emissions from air business travel 
as well as employee commute are excluded since no travel 
has been made through these means in 2020 due to various 
travel and gathering restrictions imposed by the COVID-19 
Inter-Agency Task Force (IATF) nationwide.  
Although various greenhouse gases are covered in the 
2006 IPPC Guidelines for National Greenhouse Gas 

Inventories, this accounting shall only focus on the three 
most prevalent GHG, namely the carbon dioxide (CO2), 
methane (CH4) and nitrous oxide (N2O) for Scope 1 
while only CO2 is accounted for the Scope 2 emission 
assuming complete combustion has been achieved by 
power generating plants. A summary of  the GHG covered 
in USTP-Oroquieta is shown in Table 2
In order for greenhouse gases to obtain an equivalent 
mass of  carbon dioxide, the Global warming potential 

Table 2: Direct and Indirect Emission of  USTP-Oroquieta
Emission Sources Scope CO2 CH4 N2O SF6 PFCs HFCs
Mobile combustion from owned vehicles and 
stationary combustion from generator set

1 ✓ ✓ ✓ x x x

Electricity consumption of  owned buildings/offices 2 ✓ x x x x x

Employees’ official air business travel 3 x x x x x x
Employee’s commute 3 x x x x x x
Transmission and Distribution Loss 3 x x x x x x

(GWP) is used. It is an index that attempts to integrate the 
overall climate impacts of  a specific action (e.g., emissions 
of  CH4, NOx or aerosols). Table 3 shows the global 
warming potentials of  the three GHGs based on the Fifth 

Assessment Accounting (AR5) of  the Intergovernmental 
Panel on Climate Change (IPCC) which are considered in 
this accounting. 
Data Collection and Data Quality Assurance

Table 3: Global Warming Potential Used (IPCC, 2014)
Common Name Chemical Formula Global Warming Potential
Carbon dioxide CO2 1
Methane CH4 28
Nitrous Oxide N2O 265

The data were collected from the designated personnel 
in USTP-Oroquieta. The activity data for Scope 1 were 
obtained from the Supply Inspector of  the campus while 
the data for Scope 2 were taken from Misamis Occidental 

Electric Cooperative Inc. I (MOELCI-I). Presented in 
Table 4 is a summary of  the quality of  the activity data 
collected.

Table 4: Self-assessment on the Quality of  Activity Data
Activity 
Data

Data 
Source

Data 
Collector

Quality 
Assurance

Remarks

Fuel Consumption 
(liters)

Fuel purchase 
receipts; Trip ticket

Campus 
Inspector

High The quantity and fuel type were recorded 
by the supply inspector.

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Data Analysis
Generally, the calculation of  scope emissions in the 
present study utilizes descriptive statistics. Here, the 
emissions from mobile combustion of  USTP-Oroquieta 
are from the owned motorcycle as well as the rented 
vans utilized for research and training conducted by 
the campus. In 2020, only gasoline fuel was purchased. 
Pursuant to Republic Act No. 9367 or the Biofuels Act of  
2006, “all diesel fuels sold throughout the Philippines are 
currently blended with 2% biodiesel by volume and 10% 
bioethanol by volume for gasoline,” hence a correction 
factor was used to account for the biofuels blend in the 
fuel consumption of  the campus (Official Gazette, 2007). 
The total CO2e emission from the fuel consumption of  
USTP-Oroquieta for 2020 was determined using the 
formula
Emission (tonsCO₂e)=(Activity Data)(Emission Factor)(1)
Further, the stationary combustion sources such as the 
chainsaw, lawn mower, and mixer for landscaping and 
construction of  makeshift classrooms are accounted. 
The emissions from methane and nitrous oxide were 
converted into its equivalent CO2 emission using the 
respective global warming potentials. Similarly, the 
total tCO2e emissions from stationary combustion was 
determined using the formula 

Emission (tonsCO₂e)=(Activity Data)(Emission Factor)
(GWP) (2)
The Scope 2 emission was calculated using the data 
collected from MOELCI-I and the grid emission 
factor for Mindanao obtained from the Department of  
Energy (Department of  Energy, 2020). For the entire 
campus, there is only one meter reader hence there has 
been no difficulty in obtaining the monthly electricity 
consumption. The values of  the emission factor for fuel 
combustion and purchased electricity were obtained 
from the US EPA (US EPA, 2021) and MOELCI-1, 
respectively, while no activity data have been recorded for 
Scope 3 emissions. 
Emission (tonsCO₂)=(Activity Data)(Grid Emission 
Factor)  (3)

RESULTS AND DISCUSSION
Accounting for all the greenhouse gas emissions excluding 
CO2 from biogenic sources, the total GHG emission 
from both mobile and stationary fuel combustion is 
equivalent to 0.0895 tCO2e and 0.139 tCO2e, as shown in 
Table 5 and Table 6, respectively. Adding the emissions 
from mobile and stationary combustion sources, the total 
Scope 1 emission is 0.2285 tCO2e.
The Scope 1 emission of  USTP-Oroquieta categorized 

Electricity 
Consumption 
(kilowatt hour)

Monthly electrical 
bills

MOELCI-I High The entire campus only has one electric 
meter which measures the kWh used 
in a monthly basis. A summary of  the 
electricity consumption of  the campus 
for 2020 was requested from MOELCI-I. 

Table 5: USTP-Oroquieta emissions from mobile combustion
Fuel Consumption (liters) Total tCO2e Emission 

(excluding tCO2 from biofuel)Gasoline Bioethanol
42.858 4.2858 0.0895

Table 6: USTP-Oroquieta emissions from stationary combustion
Fuel Consumption (liters tCO2 tCO2 from 

bioethanol
tCH4 tN2O Total tCO2e Emission 

(excluding Biofuel tCO2

Gasoline Bioethanol
66.71 6.671 0.139 0.0155 1.689E-04 7.8E-07 0.139

from mobile and stationary combustion sources is 
illustrated in Figure 1 while the monthly emission from 
the electricity consumption in 2020 is illustrated in Figure 
2. As can be gleaned from Figure 1, the emission from 
mobile combustion is higher than the emission from 
stationary sources having 61% and 39%, respectively.
The monthly emission from the electricity consumption 
of  the campus for 2020 is presented in Table 7. Here, 
it can be seen that the highest amount of  electricity 
consumed was on February which therefore has the 
highest emission while the lowest was observed for the 
month of  April. Overall, USTP-Oroquieta was found to 
obtain a total GHG emission of  24.7135 tCO2e. 

Figure 1: Scope 1 emission per combustion source

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Finally, since no domestic air travel nor employee 
commutate has been made in 2020 due to the COVID-19 
pandemic which imposed travel and gathering restrictions 
for safety, the campus has therefore no recorded Scope 
3 emissions. The total greenhouse gas emissions from 
various sources and operations in USTP-Oroquieta for 

Table 7: USTP-Oroquieta emissions from monthly purchase of  electricity
Month (2019) Electricity Consumption (kWh) Megawatt Total GHG Emission (tCO2)
January 2400 2.4 1.90104
February 4160 4.16 3.295136
March 2160 2.16 1.710936
April 1040 1.04 0.823784
May 1280 1.28 1.013888
June 1600 1.6 1.26736
July 2400 2.4 1.90104
August 3040 3.04 2.407984
September 3360 3.36 2.661456
October 3280 3.28 2.598088
November 3520 3.52 2.788192
December 2960 2.96 2.344616
Total 31200 31.2 24.7135

Year 2020 is summarized in Table 8. Generally, the scope 
with the highest emission is Scope 2 followed by Scope 
1 emissions which consist of  99.086% and 0.914%, 
respectively. Scope 3 emissions on the other hand has 
obviously no GHG estimate since no activities have been 
made to account for it.

Table 8: GHG Emissions by Scope or Category
Scope tCO2e % Total Emission
Scope 1 0.228 0.914
Scope 2 24.714 99.086
Scope 3 0 0
Total Emission 24.942 100

CONCLUSION
Based on the results and analyses obtained in this study, the 
author concludes that the total GHG emission produced 
from the activities and operations of  the campus for 
Year 2020 was largely contributed by Scope 2 emissions. 
Similarly, the emission from mobile combustion is higher 
than the stationary combustion constituting 61% of  the 
Scope 1 emission. 
Although most of  the operations were immobilized due 
to the COVID-19 pandemic, some activities, mostly for 
faculty development, were still conducted following strict 
health protocols. Lastly, no emission for Scope 3 has been 
recorded from the operations of  the campus for 2020 
since no air travel nor land commute was recorded even 
before the travel restrictions were imposed due to the 
pandemic.

Acknowledgements
The author would like to acknowledge Ms. Junefer 
Malinis, a faculty member of  the campus, as well as 
the Misamis Occidental Electric Cooperative Inc. I for 
providing a summary of  the monthly electricity bills of  
USTP-Oroquieta.

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