외부비용은 재화나 서비스가 생산 또는 소비되는 과정에서 제3자에게 부과되는 비용이다. 원자력 발전을 통한 전력생산에 도 외부비용이 발생하며 이들에 대한 연구가 1990년대부터 진행되어 왔다. 비용은 정책결정에 중요한 요소로 전력 생산에 대한 비용 비교를 위해 외부비용이 고려되고 있다. 핵연료주기에서도 선택에 따라 다른 외부비용이 발생되지만 이에 대한 연구는 진행되고 있지 않다. 본 연구에서는 핵연료주기 외부비용 평가 방법 개발을 위해 원자력 발전에 대한 외부비용 평가 방법을 조사하고 분석하였다. 후쿠시마 사고 이전에는 외부비용 연구들은 정상 운전 상태에서의 손상 비용에 초점을 두었 다. 그러나 사고 이후 사고비용이 주요 주제가 되었다. 사고비용을 포함한 외부비용 범위는 여러 연구들에서 다양하게 사용 되었으며 범위에 맞춰 다른 방법들이 적용되었다. 본 연구에서는 이러한 결과들이 비교되었으며 핵연료주기에 따른 외부비 용 추산에 방법적 적용성 판단을 위해 분석되었다.
Global warming has pressured companies to put a greater emphasis on environment management which allows them to reduce environmental impact and costs of their operations. In Korea, the coal-fired power plants take a large account of electricity generation at 31.7% of the total electricity usage in 2014. Thus, environmental impact of coal-fired power plants is significant. This paper illustrated how to compute environmental impact and costs in electricity generation at a coal-fired power plant using MFCA methodology. Compared to the traditional accounting, an advantage of MFCA is to provide information on electricity generation costs and environmental wastes incurring throughout the production process of electricity. Based on MFCA, the coal-fired power plant was able to reduce production cost of electricity by 52.3%, and environmental wastes by 47.7%. As a result, MFCA seemed to be an effective tool in environmental management for power plants.
To lower the operational cost of microbubble generation by electrolysis, optimization of parameters limiting the process must be carried out for the process to be fully adopted in environmental and industrial settings. In this study, four test electrodes were used namely aluminum, iron, stainless steel, and Dimensionally Sable Anode (DSA). We identified the effects and optimized each operational parameter including NaCl concentration, current density, pH, and electrode distance to reduce the operational cost of microbubble generation. The experimental results showed that was directly related to the rate and cost of microbubble generation. Adding NaCl and narrowing the distance between electrodes caused no substantial changes to the generation rate but greatly decreased the power requirement of the process, thus reducing operational cost. Moreover, comparison among the four electrodes operating under optimum conditions revealed that aluminum was the most efficient electrode in terms of generation rate and operational cost. This study therefore presents significant data on performing costefficient microbubble generation, which can be used in various environmental and industrial applications.