• Korean Journal of Soil Science and Fertilizer
• /
• v.48 no.5
• /
• pp.477-484
• /
• 2015

Environmental effect of water-saving irrigation on the emissions of greenhouse gases (GHGs) has not been well investigated. The objective of this study was to measure the effect of water-saving irrigation on GHGs as well as water use and rice production yield in paddy field condition in Korea. Four experimental runoff plots of 4x35 m in size were prepared at an existing paddy field. GHGs emission was measured during the 2012~2013 growing seasons while a Japonica rice variety was cultivated. Four different water management methods, 1) Continuous Flooding (CF), 2) Intermittent Drainage (ID), 3) Water Saving (WS), and 4) CF+WS, were used during a rice growing season to compare the effects of water management methods on GHGs emission. CF method is flooding all the time, ID method makes paddy water drained 40 days after transplanting for about two weeks, WS method maintains 2~3 cm water-level, which should be refilled when the water-level decreased to about 0 cm, and CF+WS method combines CF method before 30 days after transplanting (DAT) and WS method after 30 DAT. Regardless of water management methods, paddy field water was drained about 30 days before harvest. Amount of GHGs emission from WS plot was reduced by 69.3% compared to that from CF plot and by 59.0% compared to that from ID plot. Amount of GHGs emission from CF+WS plot was reduced by 60.7% compared to that from CF plot and by 47.5% compared to that from ID plot. Weed occurrence in CF+WS plots was reduced to 62.2% in comparison with the WS plot, implying that CF+WS plot showed the best effect to mitigation of the greenhouse gas emission in the atmosphere.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.2057-2058
• /
• 2011

We have studied that a effect saving temperature of instantaneous heater using an economical bidet due to change Silicon-Tube. The results, we have found that the existing instantaneous heater is reduced 15 [%], 20 [%] better than a new product instantaneous heater as a discharge water [${\ell}$/min] with temperature and ${\nabla}$ value, respectively. Therefore, we have showed that the innovative effect of a working process and the cost reduction because an economical bidet due to change Silicon-Tube.

• Proceedings of the SAREK Conference
• /
• 2009.06a
• /
• pp.1043-1048
• /
• 2009

This paper proposes the new operation control method that let heat source system stop and circulate only hot water at low load, and verified the introduction effect. At first, we constructed simulation model of heat source system and examined the proposing method by using simulation model. At last, we examined the introduction effect of proposing method with actual building. As a result, the primary energy consumption of heat source system was reduced by about 13%.

• Journal of Korean Society of Water and Wastewater
• /
• v.31 no.1
• /
• pp.13-19
• /
• 2017

Relatively low efficiency in anaerobic digestion process is mainly caused by unproper mixing method. In this study, tray motion type agitator was applied in actual anaerobic digestion tank in order to improve the digestion efficiency, equalize the flow velocity distribution and energy saving. The impeller of tray motion type agitator was reciprocated vertically. Gas lift type agitator and tray motion type agitator appears almost same mixing efficiency include digestion rates. However, tray motion type agitator have shown that lower energy consumption compared to the conventional gas lift type agitator. Implementation of tray motion type agitator in the anaerobic digestion tanks contributed to the stabilization of mixing environment, efficiency and energy efficiency of the tank.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2000.04a
• /
• pp.244-245
• /
• 2000

• Journal of Korean Society of Water and Wastewater
• /
• v.25 no.1
• /
• pp.51-61
• /
• 2011

A project constructing sewerage facilities in 9 upstream areas of 7 multi-purpose dams will have been completed by 2011. After all constructing and retrofitting of the new and the existing sewerage facilities, integrated management system with operation and control functions for the each levels of facilities will also be utilized. In this study, we studied how to compose the organization taking responsibility of the integrated management system and analysed human resources saving effect against conventional method of individual management of each sewerage facility. As a result, a method estimating the human resources in employing the integrated management among several sewerage facilities at upstream areas of dams were presented and some 23% of human resources could be saved by integrated management. Commissioning to a specialized public institute showed the highest B/C ratio of 4.5 among commissioning to local public corporations, commissioning to private corporations, and role-sharing partnership, etc.

• Journal of Korean Society of Water and Wastewater
• /
• v.20 no.4
• /
• pp.527-534
• /
• 2006

Demand side management(DSM) is the newly raised issues in the water resources management in recent. Many of the policy tools among demand management, the most important measures might be a pricing system. Furthermore, the responses of consumers on the price for water consumption level is the key factor for policy making. Here, we estimated panel data for 167 regions and over 7 years periods in Korea. Compare to other previous studies the price elasticities were somewhat low. The estimated price elasticity was -0.05. It was because the short term estimated period may derive lower elasticities. However, it might be a recent trend after the continuous increment of water pricing and consumers not willing to decrease their residential water consumption with increasing water pricing. According to this results, water saving effect might be much smaller than we expect with pricing policy. However, It does not imply there is no price effects on water consumption and it's still meaningful as a tool of water management.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.16 no.1
• /
• pp.26-33
• /
• 2004

In general, an absorption chiller or heat pump is operated under the constant cooling water flow rate condition even though the system works with a partial load. The objective of this paper is to study the effect of the cooling water flow rates and the temperature of cooling water on the system performance to find the energy saving methode for the partial load operation of the double effect $H_2O$/LiBr absorption chiller. It is found that the performance of the system is sensitive to the temperature of cooling water than the cooling water flow rate, so the decrease of the performance due to reducing the cooling water flow rate can be overcome with the reduction of the cooling water temperature by 1$^{\circ}C$. The flow rate of the cooling water flow rate ranges from 50％ to 100％ of the flow rate at normal conditions with a partial load. It is also found that the operation cost of the cooling water pump and the cooling tower can be reduced by 23％.

• Journal of Environmental Policy
• /
• v.13 no.1
• /
• pp.95-118
• /
• 2014

Environmental education is the most important and fundamental way to deal with the climate change. The school policy concentrating on environmental education, which has been established and financially supported by the Korea Ministry of Environment, provides an environment for natural experiment, examining the effect of reinforcing environmental education at schools on the energy-saving behaviours observed in the households concerned. We investigated the impact by applying the difference-in-difference measure to various utilities including water, electricity and gas between the households with children whose schools were designated as pilot environmental education schools in 2011 and the households with children attending general schools. The results showed that the households with children attending the pilot environmental education schools paid lower electricity and gas costs. This implies that environmental education provided at schools can indirectly affect the household energy saving behaviour and in turn reduce the total energy consumption in a short time.

• KIEAE Journal
• /
• v.15 no.4
• /
• pp.77-84
• /
• 2015

Purpose: In 2008, As the green growth policy was presented, Green Building is made any effort to propagation. In this paper, the respective technologies that are able to considerably reduce the energy demands for heating, cooling, hot-water, lighting and ventilation among the variety of technologies were selected. Method: Design factors such as (1) External insulation, (2) Triple glazing window, (3) LED lighting, (4) External venetian blind, (5) Geothermal and (6) Heat recovery ventilator were derived. In addition, energy saving effects in terms of energy demand, energy consumption and energy cost were investigated using EnergyPlus, building energy analysis tool. Result : The results were as follows. (1) It can be seen that high insulated triple glazing window, heat recovery ventilator and external insulation technology is excellent for energy demand. (2) Unlike energy demand, saving effect of energy consumption and energy cost was shown in order of Geothermal > Triple Window > Heat recovery Ventilation> Insulation> LED Lighting > EVB Blind.