• Current Photovoltaic Research
• /
• 제9권1호
• /
• pp.11-16
• /
• 2021

In the past, marine pollution caused by radioactivity and wastewater discharge caused mass destruction. As an alternative, the land farming system became common and operational. In recent years, safety and environmental problems caused by declining population due to aging of fishermen and underdeveloped facilities have always been lurking, so improvement is urgently needed. As part of the new renewable energy 3020 plan announced by the government in 2017, a new model was proposed to improve the environment as well as save energy when the roof of a water tank farm was remodeled into a solar power system. Study, when the existing roof was remodeled and replaced with a water tank farm in Busan as an empirical model, the energy saving rate was analyzed by comparing the actual electricity consumption and power generation.

• KIEAE Journal
• /
• 제16권5호
• /
• pp.39-45
• /
• 2016

Purpose: The purpose of this study is to analyze the energy saving and cost benefit analysis of the Low-income Energy Efficiency Treatment Program supported by KOREF(Korea Energy Foundation). This program was launched in 2007 and performs building energy retrofit for the low-income and energy poverty houses. Method: Energy simulation and cost benefit analysis were accomplished for the low-income detached houses. The structure of detached house was a lot og block structure, wood frame (single glass) and concrete roof. Baseline model of the low-income detached houses was proposed. Result: Annual heating energy consumptions were decreased by about 3.2% with the window system replacement(Case 1), 9.3% with reinforcement of insulation(Case2), and 12.5% with both(Case 3) compared to those of baseline model. The construction cost will be recouped within 5 years for the Case 1, 3 years for the Case 2, and 3 years for the Case 3. Case 3 was the most cost beneficient construction method in the analyzed cases in this study.

• 설비공학논문집
• /
• 제23권10호
• /
• pp.656-661
• /
• 2011

The amount of water resources that can be used tend to be decreased gradually. In contrast, the rapidly increasing water consumption is a problem that need to be addressed. Renovation and equipment replacement to improve energy efficiency and to reduce expenditure for building usage is required. But the excessive initial investment cost and the prolonged of pay back period may be uneconomical choice. Water usage for cleaning the toilet bowl accounts for 27%of the total water usage. Water-saving valve that can select the amount of water for cleaning toilet bowl can be reduced expenditure. After installing water-saving valve, analysed the economic effects. Water-saving valves compared with flush valves, and researched the amount of water usage. Then analyzed for the economic effects. Water-saving valve was used 5.6 ${\ell}$/time for cleaning toilet bowl. In contrast, flush valve was consumed 8.4 ${\ell}$/time. Water-saving valve's water-saving rate was 33.3%. The initial payback period for Water-saving valve was 459.5 days. By a small investment in water saving valve, the economic benefits can be obtained.

• 한국인터넷방송통신학회논문지
• /
• 제15권5호
• /
• pp.213-217
• /
• 2015

서울시에는 25개 구역의 구청이 있으며, 구청에는 최소 1곳에서 최대 4~5곳으로 소중대규모의 다양한 공연장을 운영하고 있다. 공연장의 용도는 연극이나 뮤지컬의 일반적인 공연에서 학예회, 발표장 등 다양한 용도로 사용되고 있다. 이 점을 착안하여 다양하게 사용되기에 용이한 LED등기구를 기존 할로겐 등기구로 대체 하였을 때 에너지 절감 부분에 대한 측면에서 어떤 이점이 있는 지를 알아보고, 실제 구민회관의 공연장을 대상으로 에너지 절감에 대한 수치로 적용하기로 한다. 기존 할로겐 등기구에서 LED등기구로 교체하였을 경우 약80%가량의 전력량 절감이 나타나며, LED자체의 소자 칩으로 다양한 기능적 특성을 가지는 장점을 지녀, 앞으로 할로겐 등기구를 대체하기에 용이한 LED 등기구라고 할 수 있을 것이다.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
• /
• pp.625-630
• /
• 2002

The availability of natural aggregates has decreased in recent years due to depleting reserves. From the viewpoint of energy and resources saving, it may be advantageous to use the waste concrete as construction aggregates. The purpose of this study is to analyze petrographic and chemical properties of recycled aggregate, and to investigate the resistance of concrete to rapid freezing and thawing by using replacement ratios (0, 10, 20, 30, 40, 50, 60, 70, 100% ) of recycled aggregate.

• KIEAE Journal
• /
• 제14권2호
• /
• pp.37-46
• /
• 2014

University buildings are energy-guzzling facility that consume more than 10,000TOE within a campus annually. Even the consumption is on an upswing trend. Behind such high consumption are there cheap power rates for education facility, lack of high-efficiency equipment and ever-increasing use of various information equipment. Being keenly aware that greenhouse gas emission increases due to such rise of energy consumption, the present study carried out a case study. In the case study, the study chose the buildings of E university from top 10 universities that consume energy most in Seoul and examined the current status of their energy consumption and greenhouse gas emission. And then it set the reduction target of greenhouse gas by year. Putting aside a middle and long-termed strategy for later endeavor, it first established the 1st year's implementation plan (2014) for energy saving and greenhouse gas reduction with limited budget and according to greenhouse gas reduction target. The plan is specified as follows. Targets for energy saving are mainly divided into two sectors: machine equipment and electric equipment. 7 ideas were proposed. Three ideas to improve machine equipment are to replace with high-efficiency boilers and chillers and to adjust the position of the cooling tower. By doing so, it was estimated that energy could be saved by 176.34TOE in total and greenhouse gas could be reduced by 370.771t$CO_2$-eq. Four ideas to improve electric equipment include the replacement with LED lights, LED emergency lights and high-efficiency motors and the installation of motion sensors. It was calculated that such replacement could conserve 1,076.08TOE (electric energy) and reduce 2,181.420t$CO_2$-eq (greenhouse gas).

• 한국콘텐츠학회:학술대회논문집
• /
• 한국콘텐츠학회 2014년도 추계 종합학술대회 논문집
• /
• pp.255-256
• /
• 2014

현재 대학공연장에 다양하고 화려한 조명을 많이 사용된다. 많은 수량이 필요한 등기구에 활용가능한 LED 등기구가 대체 선호되고, LED 등기구 장점인 에너지 절감에 대해 연구를 진행하였다. 설비와 장비에 대한 교체 비용을 포함하여 기존할로겐 등기구보다 LED등기구가 약3,000만원 정도 에너지 절감이 되는 것을 알 수 있었다.

• International Journal of Internet, Broadcasting and Communication
• /
• 제14권1호
• /
• pp.188-193
• /
• 2022

The energy efficiency of memory systems is an important task in designing future computer systems as memory capacity continues to increase to accommodate the growing big data. In this article, we present an energy-efficient last-level cache management policy for future mobile systems. The proposed policy makes use of low-power PCM (phase-change memory) as the main memory medium, and reduces the amount of data written to PCM, thereby saving memory energy consumptions. To do so, the policy keeps track of the modified cache lines within each cache block, and replaces the last-level cache block that incurs the smallest PCM writing upon cache replacement requests. Also, the policy considers the access bit of cache blocks along with the cache line modifications in order not to degrade the cache hit ratio. Simulation experiments using SPEC benchmarks show that the proposed policy reduces the power consumption of PCM memory by 22.7% on average without degrading performances.

• 한국수소및신에너지학회논문집
• /
• 제20권1호
• /
• pp.9-21
• /
• 2009

As one of the alternative solution for energy and environmental issues such as climate change, energy security, oil price, etc., hydrogen energy has been getting so much attentions these days. This paper analyzed the $CO_2$ emission, costs, and energy consumptions when the hydrogen energy was introduced to transportation, specifically in Sedan sector using the energy system model, MARKAL. As results, 21.5% of $CO_2$ emission in 2040 could be reduced and additional 76 billion dollars will be needed in the high energy price scenario. The amount of energy saving mainly due to the replacement of existing car to hydrogen vehicle was 16% of the final energy consumption in 2040.

• 한국건축시공학회지
• /
• 제12권5호
• /
• pp.548-557
• /
• 2012

In this study the thermal performance of G-PCM replaced for find aggregate in mortar specimens was evaluated using TG-DTA. As a result, it was found that when solid changed into liquid, it absorbed heat, and when liquid changed into solid, it radiated heat. In addition, the fluidity and the compressive strength of mortar with G-PCM can be applied to the floor mortar and a wall finish material. Also the higher the replacement ratio, the larger the latent heat capacity. It was found that the mortar with G-PCM slowed the increase and decrease of temperature. Thus, the duration of pleasant indoor temperature is extended by the floor and wall mortar with G-PCM. In conclusion, G-PCM is expected to reduce the heating energy consumption.