Twenty-three percent of carbon emissions come from fossil fuels used in transportation. Electric vehicles are suggested as alternatives to fossil-fueled vehicles. Cars having vehicle integrated photovoltaics (VIPV) on the roof have recently been launched, aiming to increase fuel efficiency and increase maximum mileage by supplying electricity to the vehicle when needed. VIPV needs to be light in terms of efficiency. The use of polymeric materials, made of low-iron tempered glass on the front that contributes significantly to the module’s weight, is required instead. The use of a sandwich structure with polymer material achieves nine times stiffer rigidity than an aluminum sheet of the same weight. It can be used with a weight that is half that of glass through the lightweight and light-transmitting polymer material on the front side. The concentrator photovoltaic module structure is used to compensate for various angles of incidence on a moving car, and it is advantageous because it is easy to apply and has a low weight owing to its excellent flexibility. It is possible to reduce the weight from 20 kg to less than 10 kg by limiting the use of glass.

Geothermal technology has a high level of uncertainty and, thus, requires thorough risk analysis for economic decisions. The levelized cost of energy (LCOE) is a basic economic analysis widely used in determining an investment or energy mix. Many reputable institutions and government agencies provide LCOE, to which they apply different levels of discount rates to reflect project risk. To this end, the weighted average cost of capital (WACC) is frequently used as a proxy for project risk-adjusted discount rate. However, whether using a higher discount rate for a riskier project is appropriate in calculating LCOE has not been scrutinized. The purpose of this paper is to propose a certainty equivalent method of LCOE as an alternative way for considering risk. We present a theoretical background and formula based on the utility theory, improving the probabilistic LCOE estimation methodology of previous studies. We also perform scenario analysis to show how the certainty equivalent model changes LCOE reflecting different level of risk of the individual variables, which traditional LCOE does not. Additionally, we suggest that the traditional LCOE should be used prudently, recognizing it can distort the result when an individual project has a different level of risk from the industry average.

The power industry is rapidly changing as demand for eco-friendly and stable power supply increases along with global greenhouse gas emission regulations. Small-capacity renewable power sources represented by photovoltaics and wind are continuously increasing as a form of microgrid to supply electric power to a community or island. As a result, microgrids based on renewable resources have come into wide usage around small areas or islands in Korea. In particular, the microgrid development policy of Korea is focused on electric power quality, as well as expansion in renewable energy supply for reducing greenhouse gas emissions. From 2009, the government began to develop independent carbon-free microgrids with photovoltaic and wind powers instead of traditional power diesel generators for small islands. The goal of this paper is to investigate a feasible economic microgrid topology for implementing the carbon-free island (CFI) under an acceptable level of reliability. First, we derive three scenarios of power systems including photovoltaics, wind, battery, and fuel cells. Next, we assess economic feasibility on top of the power supply reliability of the scenarios. Then, we perform a sensitivity test to suggest economic conditions for achieving the CFI goals. Finally, we present carbon-free-based microgrid models considering the CFI policy of Korea.

The study aims to conduct a comparative analysis of policies governing the expansion of renewable energy in Mongolia and selected countries. Against the backdrop of global energy transitions and Mongolia’s recent energy challenges, this research aims to identify and evaluate policy frameworks that facilitate the sustainable growth of renewable energy sources. The study delves into the unique socio-economic and geopolitical context of Mongolia, emphasizing the nation’s energy dependence on Russia. The findings of this comparative analysis provide valuable insights for Mongolian policymakers, offering recommendations for enhancing domestic policies that encourage the diversification of energy sources and attract foreign investment. By drawing on successful practices from some countries, this paper aims to contribute to the formulation of effective and context-specific strategies for Mongolia to achieve a more sustainable and resilient energy landscape.

This paper analyses the linkages between housing affordability and borrowing constraints, and the impact of the latter on housing tenure decisions in Korean cities during the period 2006–2016. The conventional aggregate measures of housing affordability provide a mixed picture. The price to income ratio (PIR) increased in major cities but the home purchase affordability, or repayment affordability improved between 2006 and 2016. Also, the access to mortgage finance increased substantially thanks to the expansion of mortgage supply, low interest rates and lenient macroprudential regulations. We investigate whether and how these changes affected household home purchases using the household-level micro data from the 2006 and 2016 Korea Housing Surveys. We construct the variable indicating the degree of borrowing constraint in terms of wealth each household faces and show that the number of borrowing-constrained households dropped significantly between 2006 and 2016. We then investigate the effect of the wealth constraint by including a measure of the degree of the borrowing constraint as an explanatory variable in the tenure choice equation, together with other key variables such as the cost of owning relative to renting. Estimation results confirm that, as expected, the propensity to home purchases declines if households are judged as wealth-constrained. It was also found that the detrimental effect of the wealth constraint on home ownership increased significantly, particularly for severely constrained households, while the homeownership rates for others improved during our study period. Our findings suggest that affordability measures that do not consider borrowing constraints may not be very helpful in gauging affordability of home purchases at the household level.