A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Energy

Thesis (M. Eng.) - Asian Institute of Technology, 2021

Today{u2019}s environment is a topic of concern not only in scientific field but also in engineering and business practice. On the global stage, there is some treaty or agreement which concerns about environmental impact of business activity and commitment of reduction which relate to international business and trading that bring about changing of Thailand{u2019}s engineering and business policy. In Thailand, the electricity grid is a large-scale public infrastructure mainly consist of transmission line crossover most areas of country to supply electricity for many of business activities to reserve well-being and quality of life of Thai people. This research is an environmental impact study of Provincial Electricity Authority (PEA){u2019}s 115 kV overhead transmission line (the Buriram - Satuk substation route case) which aim to optimize between Thailand{u2019}s electricity transmission line and global environmental impact reduction trend to approach the new green policy of country. The study has conducted following the Life Cycle Assessment ( LCA) procedures according to ISO14040 standard framework presented in five phases of impact assessment including production, transportation, construction, operation and disposal along the transmission line lifetime. The transmission line in this study is a representative line for the authority comprised many pieces of equipment such as foundations, electric poles, strand conductors and insulators that cause the environmental impacts along their 25 years of life cycle time. In accordance with this study, we have used an assessment method called ReCipe midpoint to represent all of the results as six impact categories including Climate Change (CC), Ozone Depletion (OD), Human Toxicity (HT), Fresh-water Eutrophication (FE), Metal Depletion (MD) and Fossil Depletion (FD). The study shows each of a MW-h that was transmitted bring about 3.656 x 10-1 kg CO2 eq of climate change (96.82 % from power loss in operation phase), 1.07 x 10-9 kg CFC-11 eq of ozone depletion, 4.25x 10-3 kg 1,4-DB eq of human toxicity, 2. 065 x 10- 2 kg P eq of fresh-water eutrophication, 8.80 x 10- 3 kg Fe eq of metal depletion and 1.02 x 10-1 kg Oil eq of fossil depletion which most of them occur in the production phase due to the production process of transmission line conductor except for metal depletion, it mainly comes from the foundation production.