• Journal of the Korean Solar Energy Society
• /
• v.27 no.2
• /
• pp.87-93
• /
• 2007

The demand for solar electric power systems, namely, photovoltaic system has grown steadily in our country over the last 10 years. However, the main obstacle against using photovoltaic system is the financial viability especially concerned with initial cost. The other factors affecting the economic viability of photovoltaic system are cost of electric energy, amount of electric energy produced by the photovoltaic system, discount rate, energy cost escalation rate, inflation rate, project life, and so on. Therefore, this thesis studies on the effect of various relating factors on economic evaluation of photovoltaic system in residential building by calculating payback period.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.18 no.1
• /
• pp.149-156
• /
• 2023

This research tried to develop an ESS electricity trading system linked with blockchain for energy participation consumers. For the purpose of publishing renewable energy ESS power amount and demand information, we will build a smart contract system on the blockchain DB, utilize the blockchain DB data of energy prosumers and consumers, and expand the power trading market flexibly. to provide realistic solutions. Therefore, the main contents of the development of the ESS power trading system linked to the blockchain are cloud-based web construction for ESS management, coin issuance and exchange registration for activating the blockchain, and to reflect the blockchain technology, building a blockchain database for collecting and supplying ESS-based production demand data, selecting a blockchain-based platform and building a foundation, and creating a smart contract, etc.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2017.04a
• /
• pp.885-888
• /
• 2017

In this paper, a new strategy for estimating building temperature based on the modified resistance capacitance (R - C) network thermal dynamic model is proposed. The proposed method gives accurate indoor temperature estimation using minimum variance finite impulse response filter. Our study is clarified by the experimental validation of the proposed indoor temperature estimation method. This experiment scenario environment is composed of a demand response (DR) server and home energy management system (HEMS) in a test bed.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2018.11a
• /
• pp.165-166
• /
• 2018

Researches for the development of renewable energy as a fuel substitute for global warming and depletion of petroleum resources are actively being carried out. Among them, the annual growth rate of PV generation is 20.73%, which is higher than other renewable energy sources. However, the production of 1 ton of polysilicon, which is known as a raw material for solar power generation panels, generates 2 tons of waste. As the demand for PV panels increases, the problem of the treatment of polysilicon sludge is attracting attention, and studies on the utilization of polysilicon sludge are needed. Therefore, in this study, the applicability of polysilicon sludge treated as industrial waste to the lightweight panel for architectural purposes was examined.

• New & Renewable Energy
• /
• v.4 no.2
• /
• pp.45-51
• /
• 2008

The fuel cell system is environment-friendly and energy efficient system. Especially, the fuel cell cogeneration systems providing heat and electricity to buildings have been developed and applied to a lot of sites in the world to cope with the global warming and $CO_2$ emission problem. This paper presents the result of study on the economic evaluation with super-micro fuel cell (SMFC) cogeneration system by varying the floor area ($132m^2{\sim}331m^2$) of the house, whose system capacity ranges from 0.10 kWe to 0.50 kWe. The electricity demand, heat demand, saved energy cost, and the simple pay-back period have been simulated for the various capacities of fuel cell cogeneration system. As a result, this study suggests the fuel cell system’s capacity decision strategy for a given house area. Contrary to conventional design assumptions, the smaller capacity fuel cell cogeneration system is appropriate for the house of large floor area to defense the progressive electricity tax, and the larger capacity fuel cell cogeneration system is appropriate for the house of small floor area to sell the electricity.

• International Journal of High-Rise Buildings
• /
• v.2 no.4
• /
• pp.331-340
• /
• 2013

The main topic of this paper is to show a possibility of indoor air quality enhancement and the fan energy savings in underground parking facilities by applying the demand-controlled ventilation (DCV) strategy based on the real-time variation of the traffic load. The established ventilation rate is estimated by considering the passing distance, CO emission rate, idling time of a vehicle, and the floor area of the parking facility. However, they are hard to be integrated into the real-time DCV control. As a solution to this problem, the minimum ventilation rate per a single vehicle is derived in this research based on the actual ventilation data acquired from several existing underground parking facilities. And then its applicability to the DCV based on the real-time variation of the traffic load is verified by simulating the real-time carbon monoxide concentration variation. The energy saving potentials of the proposed DCV strategy is also checked by comparing it with those for the current underground parking facility ventilation systems found in the open literature.

• Structural Engineering and Mechanics
• /
• v.10 no.4
• /
• pp.405-426
• /
• 2000

Two approximate methods based on mechanism analysis suitable for seismic assessment/design of structural concrete are reviewed. The methods involve use of equal energy concept or equal displacement concept along with appropriate patterns of inelastic deformations to relate structure's maximum lateral displacement to member and plastic deformations. One of these methods (Clough's method), defined here as a ductility-based approach, is examined in detail and a modification for its improvement is suggested. The modification is based on estimation of maximum inelastic displacement using inelastic design response spectra (IDRS) as an alternative to using equal energy concept. The IDRS for demand displacement ductilities are developed for a single degree of freedom model subjected to several accelerograms as functions of response modification factor (R), damping ratios, and strain hardening. The suggested revised methodology involves estimation of R as the ratio of elastic strength demand to code level demand, and determination of design base shear using $R_{design}{\leq}R$ and maximum displacement, determination of plastic displacement using IDRS and subsequent local plastic deformations. The methodology is demonstrated for the case of a 10-story precast wall panel building.

• Journal of the Korean Solar Energy Society
• /
• v.29 no.6
• /
• pp.14-21
• /
• 2009

The demand and installation for photovoltaic system(namely, PV) has grown steadily in Korea. However, the PV system has a various economic viability according to the PV system characteristic variables such as inverter efficiency, miscellaneous power conditioning losses, azimuth and slope of PV array, PV tracking mode, and so on. The other variables are the monthly consumed electric energy and economic related factor such as initial cost, government subsidy, maintenance cost, inflation rate, energy cost escalation rate, discount rate, etc. Therefore, this study is to present economic evaluation of PV system with those concerned factors by calculating internal rate of return, year-to-positive cash flow and net present value indices.

• Journal of the Korean Solar Energy Society
• /
• v.28 no.2
• /
• pp.10-18
• /
• 2008

This study aims to figure out typical meteorological data according to Korean time in order to evaluate building energy performance. Various methods of calculating typical meteorological data were compared and examined to improve accuracy and reliability of this study. This study analyzed and examined such methodologies as typical meteorological data for HASP/ACLD-8001, UK CIBSE TRY developed by CIBSE and prEN ISO 15927-4, (=ISO TRY) an international standard to evaluate annual energy demand of cooling and heating devices. In addition, actual data of KMA corresponding to Seoul in $1985{\sim}2005$ were statistically analyzed according to calculation methodology. The calculated typical meteorological data were compared te actual data using MBE, RMSE and t-Statistic. As a result, According to the comparison between average annual for HASP/ACLD-8001 and ISO TRY standard year, the average annual for HASP/ACLD-8001 is closer to actual measurement, showing that the use of typical meteorological data for HASP/ACLD-8001 is preferred. However, since the input format requested by current simulation is the same international standard as TRY. Therefore, it is necessary to improve accuracy of TRY calculation methodology and accordingly figure out Korean typical meteorological data based on average year.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2019.11a
• /
• pp.21-22
• /
• 2019

In order to prevent global warming according to fossil fuel use, countries around the world are making efforts through the Kyoto Protocol and the Paris Climate Change Convention. In addition, in order to prepare for high oil prices, researches such as the development of various renewable energy are being conducted. At present, the domestic production rate of energy sources in Korea is low at 18.1%, and power plants using forest biomass are being constructed to meet the domestic situation where 63% of the land is a forest. In 2015, the global production of wood pellets, a raw material for wood-based biomass power generation, was 28 million tons, up 7.7% from 2014, and has increased tenfold over the last decade. This is a result of increased demand for biomass. Korea is also increasing every year. However, biomass fly ash, an industrial by-product generated by biomass energy generation, is now being disposed of entirely, and there is little research to utilize it. Therefore, this paper will use biomass fly ash, an industrial by-product, which is currently being discarded due to a lack of separate treatment methods, as an admixture concept to contribute to solving environmental problems, developing new admixtures, improving quality, and seeking recycling plans.