• Journal of the Korean Solar Energy Society
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• v.38 no.4
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• pp.55-66
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• 2018

nZEH (net-Zero Energy House) is defined as a self-sufficient energy building where the sum of energy output generated from new & renewable energy system and annual energy consumption is zero. The electricity generated by new & renewable energy system with the form of distributed generation is preferentially supplied to electrical demand, and surplus electricity is transmitted back to grid. Due to the recent expansion of houses with photovoltaic system and the nZEH mandatory by 2025, the rapid increase of distributed generation is expected. Which means, we must prepare for an electricity-power accident and stable electricity supply. Also electricity charges have to be reduce and the grid-connected should be operated efficiently. The introduction of ESS is suggested as a solution, so the analysis of the load matching and grid interaction is required to optimize ESS design. This study analyzed the load matching and grid interaction by expected consumption behavior using actual data measured in one-minute intervals. The experiment was conducted in three nZEH with photovoltaic system, called all-electric houses. LCF (Load Cover Factor), SCF (Supply Cover Factor) and $f_{grid}$ (Grid Interaction Index) were evaluated as an analysis indicator. As a result, LCF, SCF and $f_{grid}$ of A house were 0.25, 0.23 and 0.27 respectively; That of B house were 0.23, 0.23, 0.19, and that of C were 0.20, 0.19, 0.27 respectively.

• Construction Engineering and Management
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• v.14 no.1
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• pp.58-64
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• 2013

• Journal of the Korean Society of Industry Convergence
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• v.27 no.2_1
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• pp.269-276
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• 2024

Many countries across the world are making efforts beyond reducing CO₂ levels and declaring 'net zero,' which aims to cut greenhouse gas emissions to zero by not emitting any carbon or capturing carbon, by 2050. Hydrogen is considered a key energy source to achieve carbon neutrality goals. Korean companies are also interested in building overseas green ammonia production plants and importing hydrogen into Korea in the form of ammonia. Green hydrogen production uses renewable energy sources such as solar and wind power, but the variability of power production poses challenges in plant design. Therefore, optimization of the configuration of a green ammonia production plant using renewable energy is expected to contribute as basic information for securing the economic feasibility of green ammonia production.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.18 no.4
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• pp.45-57
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• 2022

The Ministry of National Defense of the Republic of Korea is showing a lot of interest in net zero-energy buildings (NZEBs) to reduce energy consumption of military facilities and to promote green growth policy in military sector. The application of building passive technologies and renewable energies is essential to achieving NZEBs. This paper analyzed energy performance and energy cost on the conventional heating and cooling system (baseline scenario) and three different alternative scenarios (ALT 1, ALT 2 and ALT 3) applied in a hypothetical military building. A building modeling and simulation software (DesignBuilder V6.1) with EnergyPlus calculation engine was used to calculate the energy consumption for each scenario. Overall, when the GSHPs are applied to both space airconditioning and domestic hot water (DHW) production, Alt-2 and Alt-3, the amount of energy consumption for target building can be greatly reduced. In addition, when the building envelope performance is increased like Alt-3, the energy consumption can be further reduced. The annual energy cost analysis showed that the baseline was approximately 161 million KRW, while Alt-3 was approximately 33 million KRW. Therefore, it was analyzed that the initial construction cost increase could be recovered within about 6.7 years for ALT 3. The results of this study can help decision-makers to determine the optimal strategy for implementing GSHP systems in military buildings through energy performance and initial construction cost assessment.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.543-550
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• 2022

The U.S. Department of Energy conducts the Solar Decathlon competition as a student-based achievement that encourages sustainable design with energy efficiency and solar energy technologies. In the 2020 competition, the University of Nevada, Las Vegas (UNLV) team designed, fabricated, and constructed a net-zero modular house that applies innovative and highly efficient building technologies. This paper focused on the lessons learned during the early phases of this ongoing modular project. The research methodology included obtaining feedback from key project participants using a well-structured questionnaire. The results showed that the major items/challenges in the project's planning phase included selecting the modular size, planning the construction system, planning the materials and procurement, estimating costs and duration, selecting a fabricator, collaboration and communication, safety, and planning module transportation. These findings will help modular practitioners and future Solar Decathlon competition participants better understand how and what factors they should consider most during the early phases through the lessons learned.

• Journal of the Korea Institute of Building Construction
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• v.12 no.6
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• pp.615-623
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• 2012

Humanity is facing a number of serious issues associated with increased energy consumption and environmental pollution. Various studies/guidelines concerning sustainable building construction have suggested solutions to these disastrous problems, including: net-zero energy buildings, the green building certification system, and others. Sustainability pursues three expected effects: environmental, social, and economic merits. Korean Green Building Council (K-GBC) has also announced the Korean Green Building Certification System (K-GBCS) since 2003 based on sustainability. Some positive social and environmental aspects of the K-GBCS have already been reported. However, it is somewhat difficult to verify its economic merits, which are crucial to ensuring the validity of the K-GBCS. This research aims to verify the economic merits of the eco-friendly Korean-style condominiums accredited by K-GBCS. Following this, the expected economic effectiveness of K-GBCS will be examined in terms of sustainability. The underlying assumption is that the potential economic effect should reflect the actual economic merits, and should reflect the value of the housing in particular. According to the analysis of the variance, it can be concluded the value of green certified buildings is statistically higher than the value of non-certified buildings. Furthermore, it was also observed that this tendency was more dominant in Gyeonggi Province than in the City of Seoul. This may be caused by one of the variables: the proximity to downtown. In future studies, this variable should be studied in greater detail.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.2
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• pp.100-112
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• 2023

This study evaluated the contribution of carbon neutrality by calculating the carbon reduction amount and reduction intensity targeting the hydrogen pilot city and applying it to the carbon neutral reduction target. In the building sector, the reduction amount for 2030 was 10.8% on average. In addition, by 2050, the contribution to carbon neutrality of plan A was 14.1% on average, and the contribution to carbon neutrality of plan B was 15.1% on average. In the 2030 reduction amount of the transportation sector, the contribution to carbon neutrality was 138.4% on average. In addition, by 2050, the contribution to carbon neutrality in plan A was 82.5% on average, and the contribution to carbon neutrality in plan B was 74.9%. From the above research results, additional carbon reduction is possible when creating a hydrogen city, so it will be used as a basis of city-level carbon neutral model. It will also be used as a basis for technology development and investment promotion for various hydrogen supply methods in the future.

• Journal of the Korean Institute of Educational Facilities
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• v.25 no.4
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• pp.11-18
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• 2018

Global warming is happening now and inevitable. Everyone knows that immediate action should be taken to slow it down, but uncertain about the effective solution. Despite global efforts to reduce greenhouse gas emissions, sea levels are rising gradually. In 2013, Cornell University announced the Climate Action Plan(CAP) to make the campus greener, to reduce waste, and to ensure efficient use of resources. In particular, they set a goal of reducing energy use by 2050 and making carbon emissions to zero. Accordingly, the purpose of this study is to analyse the case of the master plan of Cornell Tech campus and its major buildings. Mainly, The House, faculty and student housing of Cornell Tech and the world tallest certified passive house, will be the main precedent that shows the architectural planning of passive house. Passive house technology, which was thought to be possible only in single-family houses, can be applied to high-rise buildings. If any passive house technology of The House project is actively introduced into the dormitory projects of domestic universities that are about to be built or renovated, it will be a good opportunity for the university to take the lead in preparing for global warming.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.2
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• pp.228-231
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• 2015

In power system research fields, one of current key issues is the construction and commercialization of micro grid site which is called green island, carbon zero island, energy independent island, building micro grid, etc. and various affiliated technologies have been being vigorously developed to realize. In addition, various researches about electric vehicles (EVs) are in progress and it is expected to penetrate rapidly with the next a few years. Some new load models should be developed integrating with electric vehicle loads because the EVs' deployment could cause the change of load composition rate on power system planning and operations. EVs are also resources for micro grid as well as distributed generation and demand response so that various supply and demand side resources should be considered for micro grid researches. In this paper, the load composition rate of residential sectors is prospected considering the deployment of EVs and the resource configuration of micro grid is optimized based on net present cost. In the optimization, the load patten of case studies includes EV's charging characteristics and various cases are simulated comparing micro grid environment and normal condition. HOMER is used to compare various cases and economic effects.