News on the internet in recent weeks has been filled with topics related to the “bad” air conditions in Jakarta. Reporting to the air quality monitoring site (IQ Air), on Wednesday (6/7/2022), air quality in Jakarta was included in the 10 cities with the worst air quality in the world with the AQI US index reaching 113 or the Unhealthy (Bisnis.com).
The AQI US index value is determined based on the PM2.5 concentration parameter. PM2.5 is a very small air pollutant, about 2.5 microns (micrometers) formed in the atmosphere due to the reaction of chemicals such as Sulfur Dioxide (SO2) and Nitrogen Oxides (NOx) (Katadata.co.id). These pollutants are formed from the disposal of power plants, industry, and automobiles. This pollutant source (pollutant) is the impact of increasing human activities in Jakarta which is directly proportional to the increase in energy consumption.
Concrete steps taken by the Jakarta government through the DKI Jakarta Provincial Environment Office in collaboration with Vital Strategies conducted an inventory study of air pollutants in 2020. Air pollutants inventoried include Sulfur Dioxide (SO2), Nitrogen Oxides (NOx), Carbon Monoxide (CO), PM10, PM2.5, Black Carbon (BC), and Non-Methane Volatile Organic Compounds (NMVOCs). This inventory focuses on several sectors that are suspected to be the main sources of air pollutants including the energy industry sector, the manufacturing industry sector, the transportation sector including land, sea, and aviation transportation, the commercial sector, and the domestic sector.
The inventory calculation was carried out using the Ministry of Environment Environment’s 2013 Monitoring and Evaluation Programme (EMEP) water pollutant emission inventory guidebook published in 2019 by the European Environment Agency. The method used is based on data on fuel consumption and fuel types which include oil, gas, and coal.
The results of the air pollutant inventory study show that total energy consumption in all sectors in 2018 was 440,904 TJ (TerraJoule). TerraJoule (fuel type unit) is the most widely used Gas which is 50.6% with the composition of use being Natural Gas, LPG, and BBG. Oil including IDO/HSD, Kerosene, Gasoline, Diesel, MFD, and Avtur was used at 48.9%. Coal is the fuel with the smallest composition used at 0.42% (Figure 1).
If specified for each sector, the largest energy user is the transportation sector with a total energy used of 194,860 TJ. 44% of total energy use. More complete energy use can be seen in Table 1.
Table 1 Total Fuel Usage (Source: DLH DKI 2020)
The composition of the largest type of fuel used in the transportation sector is Oil (Gasoline, Solar, MFD, and Avtur) which amounted to 191,710 TJ. In the energy industry sector, the most widely used fuel type is Natural Gas amounting to 133,103 TJ. This is under conditions in the field where power plants in the Jakarta area have used Natural Gas as the main fuel. In the housing sector, using gas fuel, namely LPG and Natural Gas, amounted to 61,175 TJ. More details can be seen in Figure 2.
The results of this inventory are then calculated to estimate the air pollution load using the equation
Where
FC = Fuel consumption type j
EF = Pollutant emission factor i from fuel j
p = sector
The estimation of the burden of air pollutants shows that the transportation sector is again the largest contributor to air pollutants compared to other sectors, especially in Nitrogen Oxides (NOx), Carbon
Monoxide (CO), PM10, PM2.5, Black Carbon (BC) and Non-Methane Volatile Organic Compounds (NMVOCs) (Table 2). Only the value of Sulfur Dioxide (SO2) pollutants is lower than in other sectors. The largest polluter of Sulfur Dioxide (SO2) is produced by the Industrial Manufacturing sector.
Table 2 Total emission burden by sector (Source: DLH DKI 2020)
The high value of air pollution loads from the transportation sector is on average caused by land transportation modes. As in the contributor of NOx of 66.7% or 45,819.67 tons/year produced from load cars/trucks. Likewise, PM10, PM2.5, and Black Carbon pollutants amounting to 87% come from land transportation, especially load cars/trucks. The reason is that the amount of diesel consumption, fuel quality, and vehicle technology contributes to the occurrence of high NOx emission loads.
While CO pollutants and NMVOCs are produced by motorcycles. Even CO emissions from motorcycle vehicles reached 200,863.67 tons or 70.16% of the total CO emissions produced by land transportation modes. Similarly, 96% of NMVOCs are produced by motorcycles. This is based on the number of which is the most compared to other types of land vehicles. Based on data compiled from BPS in 2020, the percentage of motorcycles reached 74.5% of the total vehicles or a total of 14,773,012 units so even with better fuel quality, it still contributes significantly to the burden of air pollutant emissions.
