FORMULATION AND APPLICATION OF A SYSTEM DYNAMICS MODEL FOR ESTIMATING URBAN CO2 EMISSIONS

Abstract

This study was carried to estimate energy related urban carbon dioxide (CO2) emissions by developing a system dynamics model for megacity Delhi. The observations revealed that the emissions estimated from the system dynamics model were significantly comparable to the emissions cited in literature. Emissions were estimated from the domestic, power plants and transport sectors for a time period of 1991-2021. Fuels used in the domestic sectors include Liquefied petroleum gas (LPG), kerosene (modern fuels); dung cake, crop waste and fuel wood (traditional fuels). The estimated share of modern fuels is 68% in year 1991 which is expected to reach upto 87% till 2021. On the other hand, traditional fuels share was estimated 32% in 1991, and expected to decline reaching a share of 13% in 2021. CO2 emissions were estimated from the five power plants in which three (Badarpur, Indraprastha, and Raj ghat) were coal based and the rest two (G.T. and Pragati) were natural gas based. CO2 emissions of the Badarpur power plant were (6632 Gg in 1991 and in 2006 has been estimated to have increased to 6985 and projected 6479 Gg in 2021) had maximum value which is followed by Pragati power plant (1238 Gg in 2003 and 1416 in 2006 to a projected value of 2776 Gg in 2021). A decrease in the emissions shows an active effort to increase combustion efficiency by improving the existing technologies, and the coal quality used. Comparing the CO2 emissions from coal and natural gas, the emission from natural gas was observed on the rise with an estimated increase of 1.2 times in 2021. Furthermore, emissions from natural gas were found to increase 29 times from 1991 to 2021. Transport sector emissions of CO2 were estimated by categorizing the vehicles on the basis of fuel consumption. The maximum emission was observed from the four wheelers (gasoline consuming vehicles) i.e. 878 Gg in 1991 and 3117 in Gg in 2006 and 10472 Gg projection in 2021 which is followed by diesel used in goods vehicle (D-GV) (1836 Gg in 1991, 2465 in 2006 and 2607 Gg in 2021). However, compressed natural gas (CNG) can be used as an alternative fuel to reduce these emissions. Finally, the total energy related CO2 emissions were observed to increased from 14328 Gg in 1991 to 23639 in 2009 and expected to increase to 48843 Gg in 2021. On the basis of the observations it can be concluded that the power plants were the highest CO2 emitters in 1991, however, the transportation sector will be the major contributor of CO2 in 2021. Furthermore, it is recommended that the new 111 policies have to be formulated to take care of the large amount of CO2 emissions being projected from transport sector.