• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.4
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• pp.202-211
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• 2017

In this study, the exergy that can be reflected in the energetic and economic values was used to assess the heat tariff of a district heating (DH) system instead of the enthalpy. It is difficult to directly apply the exergy to the current heat-charge system because of the complicated calculation; therefore, the difference between the supply and return temperatures was converted to the exergy-temperature difference for the ease of the heat-amount calculation. As a result of the exergy analysis for a DH substation, the exergy-temperature difference did not affect the surrounding temperature and pressure loss. The supply temperature and the maximum difference between the supply temperature and the return temperature exerted the main effect on the exergy-temperature difference. The new heat charge of a DH user was slightly reduced in winter compared with the previous charge, but the heat charges in the other seasons are almost the same. It is concluded from the assessment of the heat tariff for which the exergy is used that this tariff is more feasible for both DH suppliers and consumers compared with enthalpy.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.912-918
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• 2008

In this study, the exergy which could be reflected on energetic and economic value was used to assess on heat tariff of district heating system instead of enthalpy. Exergy is difficult to apply directly to present heat charge system because of complex calculation. Therefore, the difference between supply and return temperature was converted to the exergy temperature difference for easily calculating the amount of heat. As a result of exergy analysis for a DH substation, the exergy temperature difference were not affected on surrounding temperature and pressure loss. Supply temperature, maximum difference between supply temperature and return temperature had a main effect on the exergy temperature difference. The new heat charge of a DH user was slightly reduced in winter compared with previous heat charge. Heat charges in other seasons were almost same. It is thought that heat tariff using exergy will be appropriate in terms of both DH supplier and consumer.

• Environmental and Resource Economics Review
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• v.20 no.2
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• pp.381-398
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• 2011

Recently, electricity peaks have frequently occurred in winter, and the concerns about failure in power supply are soaring. One of reasons is due to the increase in industrial demand with economic recovery, and the increases in household and commercial demand with unusual cold waves are spotted as a primary cause. Especially, the diffusion of electricity heat pumps (EHP) has led to the rapid increase in commercial electricity demand. The EHP diffusion is mainly associated with low electricity tariff and cheaper heating and cooling costs compared to those of gas-engine heat pumps (GHP). The problem is that distorted electricity tariff and herd behaviour toward heating and cooling devices could bring about nation-wide inefficiencies in resource allocation. The key countermeasures are as follows. The electricity tariff should be readjusted to a realistic level. The tariff scheme should be so modified that consumers rationally respond to the tariff. In addition, one should find ways to effectively manage electricity demand.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.7
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• pp.1304-1312
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• 2009

The purpose of this study is to build promotive measures and to develop alternative policies of DG(Distributed Generation) by finding and analysing effects of four business environment factors related to DEPB(District Electricity Power Business) on boosting DG. In this study, four business environment factors, which are the electric power industry restructuring, electricity tariff and pricing structure, regulations for DEPB, and conflicts of stake-holding groups, are considered as independent variables. And promotion factors of DG including small CHP(Combined Heat and Power) generation, which is outcome of DEPB, are considered as dependent variables. But dependent variables including booming of new renewable energy generation due to green energy pricing incentives, the electric power industry restructuring, and electricity tariff and pricing policies were separatively considered. In this study, some policies were proposed reflecting research results of empirical demonstrative analysis, previous studies, overseas cases, etc.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.9
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• pp.599-607
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• 2008

In this study, air conditioning systems include ground source heat pump (GSHP), are evaluated for economic feasibility. The building is modeled an air conditioned for 280kW scale. This analysis is compared with the energy tariff programs of Korea and USA. The objectives of this paper are to evaluate the cost-effectiveness of the GSHP and combined system using Life-Cycle Cost (LCC) analysis, and to carry out the sensitivity analysis of key parameters. The paper considered the cases including the base case of air source heat pump and the other two alternates for comparisons. The combined system is not only a cost-effective way to the low energy consumption but also a way to avoid a high initial investment. The variations of initial investment and energy rates give a significant effect on the total LCC and payback period.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.5 no.2
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• pp.42-58
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• 1999

Packaging materials and articles that are used in food contact applications can transfer constituents in the foodstuffs. This kind of risk of possible health hazards to consumers has been generally recognized for a long time with the consequence of establishing corresponding food regulations in most developed countries. However, the language of these laws, their interpretation, and their level of enforcement vary from country to country. Accordingly, the actual migrating levels from packaging materials can be varied depending on the migration testing methods as prescribed in the national legislation in each countries. Therefore, there are needs of elimination of non-tariff trade barriers raised by sanitary and phytosanitary or technical measures under the Final Act of the UR Agreement. In this connection, the EU and USA are currently in an ongoing process of legislation harmonization to overcome potential barriers to free trade. In general, regulations governing component transfer in the USA are more complicated and comprehensive than similar regulations in Europe. In future, standard migration testing procedures for microwave heat susceptor materials and for the use of fatty food simulant should be established and also harmonized among countries. The objective of this investigation is to compare the current regulations for migration testing for plastic containers and packaging materials in USA, EU and Korea or Japan. For those regulations, Korean standards are required to be kept up with the international standards. By doing this, the related Korean regulation could be amended along with the worldwide progress for harmonization.

• Journal of the Korean Solar Energy Society
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• v.29 no.4
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• pp.28-33
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• 2009

In 2008, the global photovoltaic(PV) market reached 5.6GW and the cumulative PV power installed totalled almost 15GW compared to 9GW in 2007. Due to a favourable feed-in-tariff, Korea emerged in 2008 as the 4th largest PV market worldwide. PV power installation rose 495.5 percent to 268MW in 2008 compare to 45MW in 2007. Building integrated photovoltaic(BIPV) has the potential to become a major source of renewable energy in the urban environment. BIPV has significant influenced on the reflection by rear materials such as white back sheet and the heat transfer through the building envelope because of the change of the thermal resistance by adding or replacing the building elements. In this study, to use as suitable building materials into environmentally friendly house like green home, characteristic analysis of BIPV module according to rear materials achieved. Electrical output of PV module with white back sheet is high about 10% compared to other pv module because of 83% reflectivity of white back sheet compared to 8.4% reflectivity of other PV modules with different rear materials(black back sheet and glass). In the result of outdoor experiment during a year, electrical output of four different PV module is decreased about 3.72%.

• Journal of Energy Engineering
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• v.29 no.2
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• pp.68-78
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• 2020

According to the new climate change agreement, technology development to reduce greenhouse gases is actively conducted worldwide, and research on energy efficiency improvement in the field of power generation and transmission and distribution is underway [1,2]. Economic analysis of the operation method of storing and supplying surplus electricity using energy storage devices, and using energy storage devices as a frequency adjustment reserve power in regional cogeneration plants has been reported as the most profitable operation method [3-7]. Therefore, this study conducted an economic analysis for the installation of energy storage devices in the combined heat and power plant in the Czech Republic. The most important factor in evaluating the economics of battery energy storage devices is the lifespan, and the warranty life is generally 10 to 15 years, based on charging and discharging once a day. For the simulation, the ratio of battery and PCS was designed as 1: 1 and 1: 2. In general, the primary frequency control is designed as 1: 4, but considering the characteristics of the cogeneration plant, it is set at a ratio of up to 1: 2, and the capacity is simulated at 1MW to 10MW and 2MWh to 20MWh according to each ratio. Therefore, life was evaluated based on the number of cycles per year. In the case of installing a battery energy storage system in a combined heat and power plant in the Czech Republic, the payback period of 3MW / 3MWh is more favorable than 5MW / 5MWh, considering the local infrastructure and power market. It is estimated to be about 3 years or 5 years from the simple payback period considering the estimated purchase price without subsidies. If you lower the purchase price by 50%, the purchase cost is an important part of the cost for the entire lifetime, so the payback period is about half as short. It can be, but it is impossible to secure profitability through the economy at the scale of 3MWh and 5MWh. If the price of the electricity market falls by 50%, the payback period will be three years longer in P1 mode and two years longer in P2 and P3 modes.