Prachya Laochoo creator Singh, Jai Govind Chairperson Salam, Abdul P. Examination Committee Weerakorn Ongsakul Examination Committee PEA Scholarship donor AIT Education Cooperation Project Scholarship donor Royal Thai Government Fellowship Scholarship donor text series technical report th Pathum Thani, Thailand Asian Institute of Technology 2019 continuing eng 56 leaves : ill. + 1 online resource A serious issue for many years is Global Warming. Greenhouse Gas (GHG) emission is the most effective cause of global warming, which is Carbon Dioxide (C02). A solution to reducing the GHG emission is an installation of renewable energy and a reduction of an internal combustion engine (lCE). In these days, Worldwide Government has concerned more about using the electric vehicle (EV). The more electrical power is consumed by the number ofEV usage in order to reduce the GHG emission, the more consuming energy from the grid. In other words, the high penetration ofEV charging causes the significantly increase the grid loads. Then, the distribution of transformer loading may lead to the transformer's Loss-of-Life (LOL). This research has investigated the impact of the EV charging system and included three ways of mitigation techniques with the financial evaluation to reduce the transformer loading in commercial buildings. The first one of mitigation techniques is the installation of the solar PV rooftop. Second is the installation of the solar PV rooftop with battery energy storage system (BESS). Lastly, is the size upgrade of the transformer. The results show the impact of EV penetration causes an increase of the transformer's LOL by 25%, 4%, and 6% from the office building, shopping mall, and hotel respectively. The financial evaluation results in the terms of the payback periods for the office building, shopping mall show the good value to invest in the installing the solar PV rooftop. On the other hands, the payback periods for the hotel shows the good value to invest in the installing the solar PV rooftop and battery storage. A research study submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Energy, Research Studies Project Report (M.Eng.) - Asian Institute of Technology, 2019 Electric vehicles Photovoltaic power systems Solar energy Energy storage Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B05674 http://203.159.5.9/ait-thesis/detail.php?q=B05674 210215 20260818134302.0