The Green Remodeling Project under South Korea’s Green New Deal policy is a government-led project intended to strengthen the performance sector directly correlated with energy performance among various elements of improvement applicable to building remodeling by replacing insulation materials, introducing new and renewable energy, introducing high-efficiency equipment, etc., with public buildings taking the lead in green remodeling in order to induce energy efficiency enhancement in private buildings. However, there is an ongoing policy that involves the application of a fragmentary value judgment criterion, i.e., whether to apply technical elements confined to the enhancement of the energy performance of target buildings and the prediction of improvement effects according thereto, thus resulting in the phenomenon of another important value criterion for green remodeling, i.e., the enhancement of the occupant (user) comfort performance of target buildings as one of its purposes, being neglected instead. In order to accurately grasp the current status of these problems and to promote ‘expansion of the value judgment criteria for green remodeling’ as an alternative, this study collected energy usage data of buildings actually used by public institutions and then conducted a total analysis. After that, the characteristics of energy usage were analyzed for each of the groups of buildings classified by year of completion, thereby carrying out an analysis of the correlation between the non-architectural elements affecting the actual energy usage and the actual energy usage data. The correlation between the improvement performance of each technical element and the actual improvement effect was also analyzed, thereby ascertaining the relationship between the direction of major policy strategies and the actual energy usage. As a result of the relationship analysis, it was confirmed that the actual energy usage is more affected by the operating conditions of the relevant building than the application of individual strategic elements such as the performance of the envelope insulation and the performance of the high-efficiency system. In addition, it was also confirmed that the usage of public buildings does not increase in proportion to their aging. The primary goal of reducing energy usage in target buildings can be achieved if public sector (government)-led green remodeling is pushed ahead with in accordance with biased value judgment criteria, just as in the case of a campaign to refrain from operating cooling facilities in aging public buildings. However, it was possible to grasp through the progress of this study that the remodeling may also result in the deterioration of environmental comfort and stability, such as the numerical value of the indoor thermal environment. The results of this study have the significance of providing basic data for pushing ahead with a green remodeling policy in which the value judgment criteria for aging existing public buildings are more expanded, and it is necessary to continue research in such a direction that the quantitative purpose of green remodeling, which is to reduce energy usage in aging public buildings, and its qualitative purpose, which is to enhance their environmental performance for occupants’ comfort, can be mutually balanced and secured at the same time.

Although water is an essential element for the survival of all humankind, there are, however, still areas where water is not sufficiently supplied. It is a reality today that supplying energy for producing clean water is also difficult in such areas. This study develops a fresh water generator using solar heat, which is a clean energy source, and a small-scale desalination system which can be configured in parallel so that it can cope with various changes in the water supply situation. In addition, this study has developed a simulation program capable of estimating the optimum installation angle of a solar collector in such a way as to be suitable for the period of water demand, as well as the environment of the installation area, by allowing for the fact that it is difficult to change the installation angle or conditions after the installation of a fixed solar collector. In order to carry out these issues, this study has set up the experimental apparatus of a small-scale desalination system and obtained data on the amounts of fresh water generation depending on solar heat storage temperatures through empirical experiments. By applying the data in the simulation program, this study proposed the optimum installation angle for the necessary conditions.

Despite the international trend of actively utilizing BIM in the field of energy simulation, it is difficult to actively utilize BIM in domestic certification-related practice. As a result, the work process is not integrated and the work efficiency is reduced, such as the occurrence of redundant tasks. In this paper, the integrated process based on the BIM geometry information automated extraction module was presented and its effectiveness was reviewed and verified through self-developed automation module and uniformity and error-causing analysis. The construction of an integrated process through automatic configuration information extraction has the advantages of reducing the workload, enabling additional tasks through module function expansion, sharing information through the web, and ease of service manufacture. In addition, an experiment comparing the data of automatic and manual calculations with three subjects confirmed that automatic calculation database through automation module can produce a more reliable and uniform database with a lower proportion of human error than the manual calculation module. This not only improves the reliability of the energy simulation itself, but also reduces the human and temporal loads that occur during the post-simulation data verification process.

Various countries around the world are implementing a system to evaluate and certify the energy efficiency of buildings. Energy simulation plays an essential role in the process of evaluating and optimizing the energy performance of buildings, contributing to operation of sustainable buildings and reduction of greenhouse gas emissions. In an energy simulation, the occupancy rate, or the percentage of people using the building, serves as a critical parameter. This is essential for accurately predicting energy consumption, ventilation, and thermal comfort in a building. Various methods and tools have been developed to collect accurate occupant data, but they often face significant challenges in terms of time and cost. Existing occupancy schedules often fail to adequately reflect building types, user characteristics, and regional variations. To address this problem, research studies are being conducted to obtain more precise occupancy schedules through various methods such as surveys, physical sensors, Wi-Fi data, and deep learning models. ChatGPT has the capability to answer questions in a wide range of fields due to its extensive knowledge base. It finds applications in various domains, including building energy management, education, medicine, military affairs, construction projects, human resources, and resource movement predictions. This study introduces a methodology for estimating a building’s occupancy rate based on its use and user characteristics, utilizing ChatGPT. The reliability of the occupancy schedules generated by ChatGPT was confirmed through a survey, and this methodology exhibited high consistency compared to existing published occupancy rate references. Furthermore, after conducting energy simulations using a modeling approach similar to a real residential space, the results closely matched the actual energy consumption when employing the occupancy rates generated by ChatGPT as input values. These findings confirm the effectiveness of occupancy schedules that take into account the building’s use and characteristics in predicting energy consumption patterns for the building.

As one of the energy saving policies, the Korean government has been regulating the indoor thermal environment of public office facilities in Korea, starting with energy conservation measures in 1980. This policy, which is above 28 °C in summer and below 18 °C in winter, is causing discomfort among the occupants. The purpose of this study is to support the need to improve temperature limitation standards of the Korean public office facilities. For this purpose, the standards for the thermal environment in offices of major countries and associations were examined. Subsequently, they were compared with the Korean standards. Additionally, nine buildings of public office facilities in Korea were surveyed on the thermal environment, and PMV measurement was carried out. As a result, most of the buildings that complied with the cooling temperature standard as well as most of the buildings that did not comply were found to be uncomfortable. In conclusion, to improve the comfort of Korean public office facilities in the heating and cooling period, it is necessary to mitigate temperature regulation and regulate additional environmental factors.