This study analyzed the effect of indoor lighting energy reduction using a daylight-concentrating indoor louver system, which is a renewable energy equipment item. Daylight-concentrating indoor louver systems enhance indoor lighting by directing natural light, entering through windows, into the room via louvers. This study demonstrates significant lighting energy savings through the use of LED-linked dimming control, particularly during the transitional season, achieving an 85.65% reduction in power consumption. In contrast, the winter season showed higher cumulative power consumption due to reduced natural light availability, with a three-day average consumption of 1128.22 W compared to 836.60 W in the transitional season, representing a 25.85% increase. The illuminance distribution analysis revealed that, while winter had higher illuminance at 1 m from the window, the transitional season recorded higher values at 3 m and 5 m, indicating more effective natural light penetration. The solar altitude during the transitional season facilitated even light distribution through daylighting louvers. These findings confirm the substantial energy savings and improved illuminance distribution achieved with daylighting louvers and LED dimming control, with notable efficiency during the transitional season. Consequently, daylight-concentrating indoor louvers are confirmed to be effective in reducing indoor electric lighting energy consumption.

The occurrence of condensation and its prevention strategies are already known phenomena in physical buildings. However, the condensation problem still exists in newly constructed buildings. In the typical Korean residential unit, the balcony space is the most problematic area for condensation. This paper provides a solution for preventing condensation by considering a change from the fixed parameters of buildings to an IoT (Internet of Things) implemented real-time sensor control solution. To provide this solution, field measurements are acquired for a building diagnosis, an EnergyPlus simulation and site experiment to investigate the new parameters. The field measurements reveal that occupancy activity increases the possibility of condensation, and the control strategy involves the application of insulation, the use of ventilation, and controlling the opening of the balcony door. The insulation thickness and ventilation rate parameters are reviewed by the simulation; however, the uncertainty related to the moisture generation rate by occupants makes it difficult to ascertain the building’s physical parameters. Door and intermittent ventilation is controlled by the real-time sensor IoT experiment to block the moisture transfer and remove the moisture generation. This experiment has been confirmed to shorten the remaining time of condensation. Instead of providing a fixed parameter values for solution, applying sensor-controlled strategy is effective for uncertain cases involves with moisture generation. This study provides a control solution for condensation in vulnerable spaces and simultaneously provides a new design approach that adopts IoT applications to control the indoor conditions.

This study investigates the energy performance improvement in an aging public healthcare center in South Korea through a comprehensive “Green Remodeling” project. The building, originally constructed in 2001 before the establishment of national energy-saving standards, exhibited substandard insulation performance in its walls, roof, floors, and windows. The remodeling was designed to meet the highest current energy-saving criteria, incorporating advanced insulation techniques and energy-efficient systems. The remodeling process achieved a significant improvement in heating efficiency, with the ECO2 simulation predicting a 50% reduction in energy consumption. However, actual post-remodeling savings were approximately 10%, influenced by factors such as varying occupancy patterns and construction challenges. Despite these obstacles, the project demonstrated the effectiveness of targeted energy-saving measures in enhancing the overall performance of the building. This research underscores the importance of green remodeling as a viable strategy for improving energy efficiency in aging buildings, particularly in the context of South Korea’s carbon reduction goals. This study provides practical insights into the design and implementation of energy-saving technologies, offering a model that can be adapted for similar projects in other contexts.

This study presents a comprehensive case of green remodeling applied to a local fire station in Seoul, South Korea. The project aimed to improve energy performance through an integrated upgrade of passive systems (exterior insulation, high-performance windows, and airtightness) and active systems (electric heat pumps, energy recovery ventilation, and rooftop photovoltaic systems), while maintaining uninterrupted emergency operations. A detailed analysis of annual energy use before and after the remodeling shows a 44% reduction in total energy consumption, significantly exceeding the initial reduction target of 20%. While electricity use increased modestly during winter due to the electrification of heating systems, gas consumption dropped sharply by 63%, indicating a shift in energy source and improved efficiency. The building’s airtightness also improved significantly, with a reduction in the air change rate. The project further addressed unique challenges associated with continuously operated public facilities, such as insulating the fire apparatus garage and executing phased construction to avoid operational disruption. This study contributes valuable insights into green remodeling strategies for mission-critical public buildings, emphasizing the importance of integrating technical upgrades with operational constraints to achieve verified energy performance improvements.