Studies on the total cost of ownership (TCO) of electric vehicles (EVs) have become a crucial topic in academic research. As EVs have gained prominence globally, the volume of research on this subject has increased. However, previous review studies have not focused on examining trends in research that estimates the TCO for all types and technologies of EVs. Thus, our study aims to fill this gap by reviewing global trends and results of TCO studies on EVs. Our review employs the method of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to systematically collect and analyse 185 articles from 2011 to 2024. The contributions of our review are fourfold. Firstly, we construct a thematic research map to understand which topics are densely connected, thereby highlighting the core themes and focal points of the research field. As a result, future research should focus on reducing the TCO to accelerate EV adoption. Secondly, we show that the most extensively analysed vehicle technologies are battery electric vehicles (BEVs), while passenger cars are the most studied vehicle type. Thirdly, we differentiate the objectives of the TCO studies, identifying motivation gaps among them. We found that the primary objectives of the reviewed studies are TCO comparisons, followed by battery size and powertrain designs, policy scenario analysis, and TCO model developments. Lastly, we provide the range of TCO estimates for different types and technologies of vehicles. The average TCO for BEVs is found to be higher than that for internal combustion engine vehicles (ICEVs) across passenger cars, buses, trucks, and cargo vans. Electric motorcycles, however, buck this trend, with their average TCO being slightly lower than that of conventional motorcycles. Based on the review results, we propose several recommendations for policy implications and future studies.

As archipelagic countries, Japan and Indonesia's electricity transmission and distribution infrastructures are island-specific. They have limited network areas and face similar risks caused by climate change. Energy conservation through technical approaches to improve energy efficiency is effective in combating climate change and generates more significant economic benefits. This study examines the strategies demonstrated by Japan to improve its energy efficiency and identifies the potential of adopting those strategies in Indonesia. This research includes an in-depth literature review and benchmarking approaches to the two countries' mitigation strategies. The study found that the Japanese approaches, such as the prioritization of strict regulations, extensive use of innovative technology, and solid industrial collaboration, can be adopted to improve energy efficiency in Indonesia. We also identified several obstacles to adopting those approaches in Indonesia, such as policy inconsistencies, limited financial incentives, and fragmented governance. Adopting the Japanese approaches in Indonesia needs clear energy labeling, more integrated energy management in large industries, appropriate electricity pricing, and efficient energy service company (ESCO) schemes.