• 경영과학
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• 제26권1호
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• pp.77-91
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• 2009

It is the most important sucess factor for the electricity generation industry to minimize operations cost of surplus electricity generation through accurate demand forecasts. Temperature forecast is a significant input variable, because power demand is mainly linked to the air temperature. This study estimates the information value of the temperature forecast by analyzing the relationship between electricity load and daily air temperature in Korea. Firstly, several characteristics was analyzed by using a population-weighted temperature index, which was transformed from the daily data of the maximum, minimum and mean temperature for the year of 2005 to 2007. A neural network-based load forecaster was derived on the basis of the temperature index. The neural network then was used to evaluate the performance of load forecasts for various types of temperature forecasts (i.e., persistence forecast and perfect forecast) as well as the actual forecast provided by KMA(Korea Meteorological Administration). Finally, the result of the sensitivity analysis indicates that a $0.1^{\circ}C$ improvement in forecast accuracy is worth about $11 million per year.

• 에너지공학
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• 제11권1호
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• pp.59-66
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• 2002

수직 통합된 체제의 전력회사가 6개의 발전회사와 1개의 판매회사로 분리되고 전력거래소를 통한 전력거래가 본격화되면서 발전회사는 자체 소유 발전설비의 공급가능용량을 어떻게 활용하느냐에 따라 영업상 수익의 영향을 받게 된다. 특히, 하루 전 발표되는 한계가격(System Marginal Price, Base Load Marginal Price)에 맞도록 전력생산을 위한 발전 비용함수를 적용한다면 익일의 공급가능용량이 최적 배분됨으로써, 변동비 반영 시장(Cost based Generation Pool)과 입찰가격 반영 발전시장(Price Bidding Generation Pool)에 적용될 계통운영보조서비스의 계약 물량 산출 및 익일 생산비용의 최적화를위한 입찰전략(Bidding Strategies) 수립이 가능해 지므로 보유 설비에 대한 최적이용이 가능하게 된다. 따라서 본 논문에서는 수요예측 오차와 과거 시장운영 실적을 기초로 년 간 유지보수 계획을 수립하고, 계통운영보조서비스에 대한 계약물량 산출과 개개 발전기의 비용함수 산출, 적용을 통한 발전설비의 효율적인 입찰 방안에 대해 논하고자 한다.

• 동력기계공학회지
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• 제19권1호
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• pp.24-30
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• 2015

Geothermal energy is used in various types, such as power generation, direct use, and geothermal heat pumps. Geothermal energy with high temperature have been used for power generation for more than a century. The purpose of the study is to investigate flow and electricity power characteristics of hydraulic turbine for power generation of geothermal heat pump type with closed-system. The differences between the four types of hydraulic turbine, are different from the blade shape, volume, angle and etc. In case of prototype(1), pressure at blade was reduced to 2.1 bar, the kinetic energy of blade increased by increasing flow velocity(4.1 m/s). The increase of flow velocity at the blade edge markedly appeared, to increase the kinetic energy of the rotating shaft. In case that gateway in hydraulic turbine was installed, operating torque and RPM(1,080) of the rotating shaft increased respectively. Although rotational speed of prototype(2) compared to prototype(1) was reduced, the power generation capacity was greater about 3.4 times to 97 W. The most power of 255W was generated from prototype (4).

• 자원ㆍ환경경제연구
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• 제30권4호
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• pp.607-625
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• 2021

본 연구는 우리나라 발전 부문의 원자력과 신재생에너지 발전의 온실가스 감축효과를 추정하고, 원자력 발전의 사고위험에 따른 외부비용을 포함한 발전 비용을 고려하여 두 발전원의 온실가스 감축비용의 효율성을 비교하였다. 모형의 추정결과, 원자력 및 신재생에너지 발전 1% 증가는 각각 0.744%와 0.127%의 CO₂ 배출량을 감축시키는 것으로 분석되었다. 이는 CO₂ 배출량을 1% 감축시키기 위해서는 원자력 발전은 1.344%, 신재생에너지 발전은 7.874% 증가시켜야 함을 의미한다. 추정된 계수와 원자력 발전의 외부비용 포함 발전비용을 사용하여 1%의 CO₂ 배출량 감축을 위한 총 비용을 도출한 결과, 전체 발전량이 1MWh로 가정할 때 CO₂ 배출량 1%를 감축시키기 위한 원자력 발전비용은 외부비용에 따라 0.72~1.49달러로 계산되었으며, 신재생에너지 발전비용은 6.49달러로 나타났다. 이를 2020년 우리나라 총 화석연료 발전량(352,706GWh)을 기준으로 계산할 경우, 원자력 발전은 2.54억~5.26억 달러, 신재생에너지 발전은 22.89억 달러로 신재생에너지 발전이 원자력 발전보다 4.35~9.01배의 비용이 더 소요되는 것으로 분석되었다. 따라서 발전 부문의 온실가스 감축을 위해서는 원자력 발전이 신재생에너지 발전에 비해 높은 비용 효율성을 가지는 것을 알 수 있었다.

• KIEE International Transactions on Power Engineering
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• 제5A권2호
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• pp.199-203
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• 2005

This paper proposes the level of price cap in the TWBP(Two- Way Bidding Pool) market in Korea for which the draft of market design has been prepared by KPX. Max - GMCP(Maximum Generation Market Clearing Price) and APC(Administered Price Cap) would be separately applied as individual price caps for a normal period and a Price Capping period in TWBP. The level of price cap is determined for inducing optimal investment in the Korean Electricity Market considering the 'electricity resource baseline plan' published by the Korean government in 2002 for maintaining government-leading resource planning in Korea. In this regard, Max - GMCP is calculated from the equilibrium condition of investment based on reliability standard and fixed cost of the peaking plant. For verifying the propriety of the proposed price cap, this paper compares the proposed value with the estimated VoLL(Value of Lost Load) based on Korea's GDP(Gross Domestic Product).

• 유기물자원화
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• 제20권1호
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• pp.41-49
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• 2012

이형반응기 미생물연료전지(MFC) 시스템의 전기생산에 미치는 운전온도 및 전극간 거리의 영향에 관한 실험실 규모 실험을 수행하였다. 외부저항이 $(100\;{\Omega})$인 조건에서 시스템의 평균온도가 $30^{\circ}C$에서 $34^{\circ}C$로 증가할 때 외부저항 양단의 전압은 약 1.4배 증가하였다. 운전온도의 증가는 MFC의 OCV(open circuit voltage)를 증가시키며, 전극간 거리가 감소하고 운전온도가 증가함에 의해 최대전력이 얻어지는 전류가 상승하는 것으로 나타났다. MFC 시스템의 운전온도 증가에 의해 모든 전극간 거리조건에서 최대전력밀도가 크게 증가하였다. 시스템의 평균온도가 $4^{\circ}C$로 증가할 때 5~10 cm의 전극간 거리에서 얻어지는 최대전력밀도는 1.9~2.4배 증가하였고 동일한 온도조건에서는 전극간 거리가 감소할수록 전력수율이 증가하였다. MFC의 전기생산에 미치는 운전온도와 전극간 거리의 영향은 시스템의 내부저항과 밀접하게 관련되어 있는 것으로 나타났다. 즉, MFC의 운전온도가 증가하고 전극간 거리가 감소함에 의해 시스템의 내부저항이 감소함으로써 전기생산이 증가하였다.

• 한국태양광발전학회지
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• 제6권1호
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• pp.45-55
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• 2020

Although Sri Lanka's current carbon footprint is much less compared to other developing countries, the country's existing and planned economic developments have raised the demand for power, resulting an increased GHG (Greenhouse gas) emission. GHG in Sri Lanka is emitted mostly by the burning of fossil fuels for energy generation including transport. However, the most effective way of reducing GHG emissions from the energy sector is to use renewable energy sources. Solar is in the top list of renewable resources that has much potential to use to meet the demand for electricity generation in the country. The purpose of this study is to evaluate the current status of solar power generation and opportunities, barriers for implementing the programs of solar energy in Sri Lanka. Literature reviews mainly used as the primary tool for this study. Sri Lankan government had set the targets for adding 200 MW to the national grid by 2020, and to increase up to 1000 MW by 2025 of solar electricity. To achieve these targets the prevailing barriers have to be considered.

• 자원ㆍ환경경제연구
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• 제9권5호
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• pp.811-827
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• 2000

Since improved thermal efficiency reduces capacity requirements and energy costs, electricity producers often treat thermal efficiency as a measure of management or economic performance. The conventional measure of the thermal efficiency of a fossil-fuel generation system is the ratio of total electricity generation to the simple sum of energy inputs. As a refined approach, we present a novel thermal efficiency measure using the concept of the Divisia index number. Application of this approach to the Korean power sector shows improvement of thermal efficiency of 1.1% per year during 1970-1998. This is higher than the 0.9% improvement per year given by the conventional method. The difference is attributable to the effect of fuel substitution. In the Divisia decomposition context, we also show the limitations of the popular $T{\ddot{o}}rnqvist$ index formula and the superiority of the Sato-Vartia formula.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.736-738
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• 2005

For calculating optimal generation composition of The Basic Plan of Long Term Electricity Supply & Demand, the Screening Curve Method that using generation cost for planning is needed. This paper will induce optimal power system ratio included Combined Head and Power and suggest the method for optimal generation composition of The Basic Plan of Long Term Electricity Supply & Demand that considered policy side.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.180-183
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• 2008

This paper is about the ocean current power generation using sea water incoming into the lake surrounded by barrages and sea water discharged from a dam made of artificial structures. In operation of a tidal power plant, the sea water discharged from a turbine structure and a gate structure of a tidal power plant is faster than the tidal current caused by tides in nature and has better characteristics than that to run ocean current turbines. It is shown that the sea water discharged after generating electricity through a turbine generator of a tidal power plant and the sea water discharged from a gate structure of a tidal dam still have kinetic energy high enough to run an ocean current turbine and produce valuable electricity.