Managing energy transitions in developing countries is essential to ensuring a stable and affordable energy supply for both society and industry. The social, economic, and environmental impacts of this transition are typically assessed using various energy models, with dynamic system approaches providing a more comprehensive representation than conventional methods. This study presents an Indonesia's energy system dynamics model, co-developed with key stakeholders—including experts from technical ministries, research institutions, NGOs, and energy companies—to evaluate energy security policies. A participatory approach enabled stakeholders to define the model's structure, select data, formulate policy scenarios, and assess simulation outcomes through meetings and focus group discussions, ensuring transparency and credibility. Stakeholders also play a crucial role in implementing scenario analyses and simulation insights. Notably, they emphasize the importance of maintaining fossil fuel supplies toward energy security, highlighting that policy modeling in Indonesia cannot overlook fossil fuel considerations. The resulting Participatory Energy System Dynamics Model (P/ESDM) integrates five interconnected sub-models: Demography and Macroeconomics, Final Energy Demand and Total Emissions, Total Energy Supply, Policy Interventions, and Impact Assessments. P/ESDM was applied to simulate eight policy scenarios, including oil production strategies, crude oil export restrictions, refinery capacity expansion, electric vehicle promotion, biodiesel blend mandates, renewable energy capacity expansion, coal production management, and urban gas network development. Policy implications are derived from simulation results, and the model offers adaptability for other nations pursuing energy security.

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.

Indonesia has large renewable energy resources that are not always located in regions where they are needed. Sub-sea power transmission cables, or island links, could connect Indonesia's high-demand islands, like Java, to large-resource islands. However, the role of island links in Indonesia's energy transition has been explored in a limited fashion. Considering Indonesia's current fossil fuel dependency, this is a critical knowledge gap. Here we assess the role of island links in Indonesia's full power sector decarbonisation via energy system optimisation modelling and an extensive scenario and sensitivity analysis. We find that island links could be crucial by providing access to the most cost-effective resources across the country, like onshore photovoltaics (PV) and hydropower from Kalimantan and geothermal from Sumatera. In 2050, 43 GW of inter-island transmission lines enable 410 GWp of PV providing half of total generation, coupled with 100 GW of storage, at levelised system costs of 60 US$(2021)/MWh. Without island links, Java could still be supplied locally, but at 15% higher costs due to larger offshore floating PV and storage capacity requirements. Regardless of the degree of interconnection, biomass, large hydro, and geothermal remain important dispatchable generators with at least 62 GW and 23% of total generation throughout all tested scenarios. Full decarbonisation by 2040 mitigates an additional 464 MtCO2e compared to decarbonisation by 2050, but poses more challenges for renewables upscaling and fossil capacity retirement.

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.

Indonesia has committed to achieving net zero emissions by 2060, with emphasis on the electricity sector eliminating harmful gas emissions by that year. Using the Balmorel energy model, this study simulated the impact of the target on optimal capacity expansion, electricity production mix, emissions, and electricity supply costs across 230 grid systems. The results indicate the substantial benefits of integrating solar photovoltaics (PV) and Battery Energy Storage Systems (BESS). Solar energy sees a remarkable capacity increase, reaching 288.7 GWp by 2060. Other renewable sources, including hydro and wind energies, also exhibited significant growth, increasing from 6.2 GW and 130 MW in 2030 to 29.4 GW and 22.5 GW, respectively, by 2060. Intermittent renewables’ growth necessitates a rise in BESS capacity from 1 MW in 2022 to 73.4 GW by 2060. The study also underscores to replace phased-out coal-fired power plants with nuclear power by 2060. The study concludes with policy implications arising from these findings.

Burdened by oil imports and subsidies for more than 5000 diesel power plants, Indonesia aims to use crude palm oil (CPO) as fuel in the power plants. Previous studies only focused on the technical feasibility of using CPO. Therefore, this study aimed to enrich the existing literature by analyzing the technical feasibility of using CPO, degummed CPO, and bleached palm oil (BPO) fuels on endurance test for 500 operational hours with a 20 kW diesel engine capacity for each type of fuels. Our analysis included component rating and the measurement of specific fuel consumption, emissions, oil dilution, and deposit materials. The assessment concluded that diesel engines using CPO, BPO, and degummed CPO increased specific fuel consumption, deposit formation, and emissions of carbon monoxide and carbon dioxide compared to engines using a 30% FAME blend in HSD or Biodiesel 30. This implies that CPO, BPO, and degummed CPO could be used in diesel engines, though fuel consumption and maintenance costs tend to increase. Based on the test results, we provided an efficient CPO supply chain from CPO mills to diesel power plants.

Electricity subsidies in Indonesia remain high and tend to increase. Existing studies generally propose electricity subsidy reform through economic price adjustment; however, this option potentially arises political and social conflicts. The government and the State Electricity Company have also undertaken several measures to decrease electricity supply costs but those measures remain ineffective due to increasing energy prices needed as fuels for power generations. Our study analyses the effectiveness of two alternative grants for LED lamps and rooftop photovoltaic (PV), to reduce electricity subsidies for low-income residential customers with 450 VA and 900 VA electricity capacity limits. The analysis result is that replacing existing lamps with LED lamps for all those customers will cost the government US$ 313.7 million but potentially decrease electricity subsidies to US$ 208.7 million/year for 15 years. On the other hand, installing the rooftop PV system is ineffective to bring down the electricity subsidies. The investment cost of the on-grid rooftop PV system is between US$ 827.6 and US$ 1,310.3 per house, while the electricity subsidy savings for 20 years are between US$ 724.1 and US$ 744.8.

Failures of countries to set and achieve renewable energy targets are prevalent, producing uncertainty as to the possibility of renewable energy contributing to a reduction in global emissions. Lack of policy and incorrect modelling analyses are among the sources of these failures and understanding these two sources is crucial for improving confidence in renewables. We assess errors in projections pertaining to the capacity and production of renewable energy in the United States and those countries of the European Union that have strong commitments to green energy supply. Our results show that solar energy has the lowest level of uncertainty as it has the most achievable capacity projections. However, other renewables entail more attractive policies and further research is needed for the advancement of reliable technology and accurate weather predictions. Our findings also provide ranges for the projection uncertainties for six renewable energy technologies, drawing attentions to ways that the dominant errors in these renewable energy projections may be rectified.