DOI: 10.14457/tu.the.2014.86
title: Energy system and GHG emission modelling: analysis of transport sectors of Thailand and Sri Lanka

description: Rapid progress in the developing Asia in recent past has brought the attention of international community towards it, mainly due to its increasing share in global GHG emissions. Thailand and Sri Lanka, as two developing countries in Asia, have undergone expansion in their energy systems to keep up with rapid economic growth and expansion in populace; thus, have increased their contributions in global GHG concentrations. In both countries, transport sector is one of the largest GHG emitting sectors which seconds only to power sector. It is one of the top energy consuming sectors in both counties. Hence, GHG mitigation in transport sector will influence greatly on national emissions. In addition, its dependency on imported fossil oil has improved its prominence as a potential area for GHG mitigation in both Thailand and Sri Lanka.     The aim of this study is to analyze GHG mitigation potential in the transport sector of Thailand and Sri Lanka under Low carbon Society (LCS) and carbon tax policies. Separated sets of scenarios are defined to represent probable GHG mitigation pathways under two policies. Under LCS policy, four scenarios are developed by taking implementation time frames of countermeasures as the basis since delay in implementations will hinder the actual mitigation potential. Those are L2015 (time frame 2015-2050), L2025 (time frame 2025-2050), L2035 (time frame 2035-2050) and FS (only fuel switching action has modeled from 2015-2050). The FS scenario is modeled only in Thai transport sector since fuel switching action is only initiated in Thailand. Rest of the LCS scenarios is modeled evenly in Thailand and Sri Lankan models. Under carbon tax policy, three scenarios are defined namely CT50 (constant rate of 50 US$/t-CO2eq from 2020-2050), CT100 (constant rate of 100 US$/t-CO2eq from 2020-2050) and CTIN (incremental rates of 20, 50, 100 US$/t-CO2eq in 2020-2029, 2030-2039 and 2040-2050, respectively). In addition, combined effect of above defined carbon tax schemes and modal shift and TDM actions were investigated using three more additional scenarios. Along with BAU, all countermeasure scenarios are analyzed separately in Thai and Sri Lankan transport models by using Asia-Pacific Integrated Model (AIM/endues) which is bottom-up recursive dynamic optimization model.       Results show that LCS scenarios have can mitigate GHG emissions than carbon tax scenarios in both countries. In fact, L2015 scenario has the highest mitigation potential where it has cumulatively reduced 23.1% GHG emissions in Thailand when compared to BAU in 2010-2050, while that figure relevant to Sri Lanka is 13.7%. Not only can it provide more mitigation potential, but also it can bring more sustainability to transport energy systems by reducing total energy consumption, diversifying fuel mix with biofuel promotion and shifting modal mix towards efficient public modes. In carbon tax scenarios, aforementioned changes can be observed; but the effect is lower. Although combined scenarios have improved that effect, their performances are still lower to the levels of LCS scenarios. On the other hand, abatement costs are lower in carbon tax scenarios than in LCS ones in both countries. In addition, in terms of co-benefits, emissions of local air pollutants have reduced, while energy security has been positively affected under both policies in both sectors. Yet, LCS has the edge over carbon tax in it too. Nonetheless, results show that delaying implementations of countermeasures has dropped the mitigation potentials in LCS scenarios in both Thailand and Sir Lanka. Thus, overall, it can be seen that LCS scenarios can improve the sustainability in both countries while achieving significant reduction in GHG mitigation.