According to the International Energy Agency (IEA, 2022), diesel accounts for more than 17% of total global final energy consumption. In Vietnam, the Vietnam Oil and Gas Group (PVN) also recorded DO as one of the petroleum products with the largest annual consumption output. Therefore, the emission factor of DO oil is both meaningful in greenhouse gas inventory and the basis for planning emission reduction policies, ensuring our country's commitment to achieving the Net Zero target by 2050. So how to calculate DO oil emission factor? Let's find out more details with GREEN IN in the content below!
DO Oil Emission Factor: Legal Basis Guide
Determination and application of DO oil emission factors are carried out based on both international guidelines and domestic legal basis.
International Guidelines (IPCC Guidelines 2006/2019):
- Provides default emission factors for DO oil in energy units (tonnes CO₂/TJ).
- Define calculation levels (Tier 1 – Tier 3) based on data detail and emission factors.
- Is a scientific basis to ensure consistency and transparency when reporting emissions.
Legal framework in Vietnam:
- Law on Environmental Protection 2020: Regulations on the responsibilities of organizations and enterprises in inventorying greenhouse gases and implementing emission reduction.
- Decree 06/2022/ND-CP: Specify mechanisms to reduce GHG emissions and protect the ozone layer; require facilities that use a lot of fuel (including DO oil emission coefficients) to inventory and report.
- Circular 01/2022/TT-BTNMT: Provide technical procedures for GHG inventories, including how to collect activity data, apply emission factors, and prepare reports.
- Decision 2626/QD-BTNMT year 2022: Announcement of the list of emission factors for greenhouse gas inventory, in which DO oil has a CO₂ emission factor of 74.100 kg CO₂/TJ, applied to national and corporate inventory reports
What is the DO oil emission factor?
According to Decision 2626/QD-BTNMT (2022), the CO₂ emission factor of diesel oil is 74.100 kg CO₂/TJ (Tier 1 - default coefficient). This coefficient is equivalent to about 2,68 kg CO₂/liter of DO oil or 3,16 kg CO₂/kg of DO oil, which is the basis for converting fuel consumption to actual CO₂ emissions. Applying the DO oil emission coefficient helps businesses and management agencies measure emissions accurately, serving greenhouse gas inventory reporting and planning emission reduction solutions.
Compared with other fuels, the emission factor of DO oil is higher than that of natural gas (56.100 kg CO₂/TJ) and LPG (63.100 kg CO₂/TJ), almost equivalent to that of gasoline (73.300 kg CO₂/TJ), but lower than that of coal (98.300 kg CO₂/TJ). This figure shows that DO oil is popular and has high efficiency, but at the same time it contributes significantly to total CO₂ emissions if not combined with energy saving measures and the use of alternative fuels.
Method of calculating emissions from DO oil
The method of calculating the DO oil emission factor is performed according to the standard formula of IPCC:
CO₂ Emissions = Fuel Consumption Activity × CO₂ Emission Factor
In which, consumption activities are calculated in liters, kg or energy consumed (TJ), and emission factors are taken from IPCC or Decision 2626/QD-BTNMT if applied in Vietnam.
Illustrative example: A facility consumes 1.000 liters of DO oil (1 liter ≈ 0,832 kg), the total mass is 832 kg. With a CO₂ emission factor of about 3,16 kg CO₂/kg DO oil, the amount of CO₂ emitted will be:
832kg × 3,16kg CO₂/kg = 2.627,52 kg CO₂(≈2,63 tons CO2)
The IPCC classifies the calculation levels:
- Tier 1: Use default coefficient (Tier 1).
- Tier 2: Use national emission factors, reflecting fuel characteristics in Vietnam.
- Tier 3: Based on actual measurement data or detailed models, with the highest accuracy.
The choice of calculation level depends on the purpose of the emissions inventory, the data collection capabilities and the transparency requirements of the business or regulatory agency.
Factors affecting DO oil emission coefficient
Although the DO oil emission factor has been regulated in international documents and Vietnamese law, in reality this value can change depending on many technical factors and operating conditions.
First, Chemical composition and quality of DO oil: DO oil has different carbon content depending on the refining source and quality standards. High sulfur content does not directly increase CO₂ emissions, but affects combustion efficiency and generates additional SO₂, causing air pollution. In contrast, high quality DO oil with low sulfur content often provides cleaner combustion efficiency, reducing unwanted emissions.
Monday, Engine technology and combustion efficiency: New engines designed to Euro IV, V or VI standards often have higher energy efficiency and better exhaust gas treatment systems, thereby reducing emissions per unit of fuel consumed. In contrast, old engines that are not properly maintained are prone to incomplete combustion, increasing CO₂ emissions along with other gases such as CO, NOx and fine dust, thereby increasing the DO oil emission factor.
Tuesday, operating conditions: When vehicles or equipment are operated under overload, under poor maintenance or in harsh environments (high temperatures, high humidity, or high altitudes), combustion efficiency is often reduced. This increases fuel consumption per unit of power produced, resulting in higher CO₂ emissions than theoretically calculated.
Conclusion
In general, mastering the DO oil emission coefficient not only helps businesses meet legal requirements and transparent reporting, but also brings opportunities to optimize energy costs, improve the image of "green businesses" and contribute positively to Vietnam's climate change mitigation goals. This is an important step, connecting science - technology - policy, aiming towards a sustainable and low-carbon economy.