Kim J, et al. Yonsei Med J. 2022 Mar;63(3):296-303. https://doi.org/10.3349/ymj.2022.63.3.296

The Maldives, one of the Small Island Developing States (SIDS) with great solar potential, is keen to promote renewable energy systems to reduce its heavy reliance on imported diesel for power generation. However, adopting renewable energy systems is still burdensome for the Maldives not only because of its high initial costs and insufficient financial resources but also because of a lack of understanding about whether the deployment of a renewable system is economically feasible. Therefore, the concept of grid parity is explored as an important concept in this paper to examine the possible timeframe for reaching it. A distinctive feature of the paper is that the paper used actual cost and technical information to analyze the levelized cost of energy (LCOEs) of the independent renewable system in a remote island and examined its timeframe for reaching the grid parity condition. Based on economic and technical information from a project for replacing existing diesel generator to photovoltaic (PV) with energy storage system (ESS) in Kuda Bandos Island in the Maldives, the paper considers three different system configurations and evaluates which configuration could result in the most optimal off-grid energy systems in this remote island. With sensitivity analysis on various uncertainties, the paper shows the range of the levelized costs of energy and the periods required for reaching grid parity for deploying solar photovoltaics and ESSs in Kuda Bandos Island, Maldives. The result indicates that the photovoltaic system is an economically feasible option for the resort, and that grid parity can be reached within the project lifetime. However, the result shows that the use of advanced ESSs is still an expensive option and would not be economically reasonable.

The demographic changes of East Asian countries have accelerated in recent years. With consideration of the linkage between human behavior and carbon emissions, it is necessary to consider demographic characteristics for the CO₂ emission projections of these countries. This study examines how changes in the demographic structure affect the emission projections of three East Asian countries (South Korea, China, and Japan) by comparing two different vintages of population projections. The study constructed a dynamic computable general equilibrium (CGE) model and applied the most up-to-date dataset of population prospects, GTAP 10, and the labor force participation rate. By comparing UN2010 and UN2019 projections, the study examined the impact of demographic changes on CO₂ emission profiles of the three East Asian countries. The simulation result showed that GDP, which represents economic activity along with the population, is the direct channel of CO₂ emission projections. Moreover, the scenario analysis suggested the population factor as one of the main drivers of the CO₂ emission projection and a clear positive relationship between GDP and CO₂ emissions, though CO₂ emissions are generally inelastic in response to a GDP decrease in the three East Asian countries. The finding indirectly implies that not only the size of the population but also demographic composition should be considered to project CO₂ emissions, as the labor participation rate is an important factor to determine the production function.

Based on actual measurement data from a resort in the Maldives, this paper explores the criteria for the optimal off-grid renewable energy systems that contribute to greenhouse gas mitigation and climate adaptation efforts from three perspectives: technical, economic and environmental. Using Hybrid Optimization of Multiple Electric Renewables software, the optimal technical combination of hybrid energy system is determined. Moreover, indicators such as levelized cost of energy and net present cost are considered as economic criteria to determine the financial feasibility of the off-grid renewable energy systems. Finally, CO2 emission level and renewable shares are reviewed from environmental perspective.

In April 2023, the Korean government announced its national emission pathways to achieve its 2030 NDC target of reducing GHG emissions by 40% compared to the 2018-level. The study provides an overview of the economic impacts of achieving the NDC target on the Korean economy, and particularly, it considers the different circumstances of the global mitigation efforts. The study collects the countries’ NDC target information, applies a global dynamic recursive CGE model with GTAP 11 database, and establishes seven scenarios with different global mitigation efforts and the recycling of carbon revenues. Three types of international cooperation scenarios are Global Cooperation, Partial cooperation without Korea, and Unilateral Commitment by Korea. The utilization of carbon revenues is another dimension of the scenarios. The result indicates that all regions experience negative impacts on real GDP under the Global Cooperation scenario with lump-sum tax transfer approach. With the labor tax recycling, the losses in real GDP decrease, and some regions, including Korea, show some positive economic impacts. Particularly, Korea experiences substantial benefits from double dividend. Moreover, Korea experiences relatively favorable impacts of carbon pricing on real GDI. In addition, all scenarios indicate some decrease in real exports and imports in all regions, and the result suggests that carbon pricing would lead to significant negative impacts on production, particularly of fossil fuel sectors. We also conduct a sensitivity analysis on key parameters, such as the elasticities of substitution between energy and genuine input factors, as well as those between different sources of energies.