에너지 모델링을 통한 도시의 탄소저감방안에 대한 생태경제적 평가

Abstract

Abstract Research to solve the global climate change crisis by reducing greenhouse gas emission and to achieve sustainable development of urban is in process. It is desirable to reduce nonrenewable energy use by greenhouse gas reduction, but the change of system should be evaluated to adapt the ripple effects. The aim of this study is to confirm the present condition of urban system and to predict the changes of urban system by the policy for responding to climate change crisis through the approach of system ecological method. In this study, we selected Busan metropolitan city as a target site and studied the system of Busan using Emergy evaluation from 1998 to 2007. As the result, energy basis of Busan includes environment energies such as sun, rain, river, tide, wave, earth cycle and purchased input such as supplied coal, oil, gas, electricity, good & service from out of system boundary. Total emergy of Busan was shown 5.82E22 ～ 6.91E22 sej/yr and about 84% of it was purchased sources from outside. Emergy flows from the environment was shown about 10 percent in total emergy in Busan. The emergy from river was shown the highest proportion in the environment energy resource, and the emergy from tide was the next. Emergy yield ratio(EYR) and Emergy investment ratio(EIR) of Busan in year 2007 were 1.12 and 8.05. Also, Environmental loading ratio(ELR), showing the ratio of rising environmental load from the development of urban system was 8.14, which is similar with the ELR of South Korea. Emergy Sustainability. Emergy Sustainability index(ESI) was 0.14, which means Busan has a low sustainability level. We tried to predict the future of Busan after 2007 based on the data from Emergy analysis and statistical analysis, and also considered applying the reduction plan of Greenhouse gas emissions of Busan. Predicted amount of purchased input shows a clear increment trend until 2020. The green house gas emission reduction plan made to reduce the amount of purchased input slightly but there was no significant change to emergy indices such as EYR, ELR or ESI. The results of simulation on greenhouse gas emission of Busan shows decrement of stored environmental resource(Q) and money(M) due to the increasing of economical asset(A) and the consumption of the city. The simulation also shows the prediction on amount of greenhouse gas emissions(C) which increases steadily until 2020, the amount of export(Ex) decreased gradually. In the case of applying reduction plan of greenhouse gas emissions on the simulation, Economical asset(A) slowed it increment. The Money storage(M), and the amount of export(Ex) also decreased due to the reduction of fossil fuels use. The increasing trend of greenhouse gas emissions(C) was switched to decreasing by 15% until 2020. However, applying the reduction plan of greenhouse gas emissions did not occur the positive changes to emergy indices. Therefore we applied the reduction plan and increased usage of renewable energy source by 10% per year on the simulation. The result of the simulation shows the reduction in greenhouse gas emission and increment on emergy sustainability index(ESI) in Busan. The result of performing the simulation through various stages for the realizability of sustainable city, more amount of greenhouse gas emissions(C) decreased while emergy sustainability index(ESI) increased up to 0.98 in the case of applying the reduction plan and to 40% increase on usage of renewable energy source per year simultaneously. These results indicate that the transition in industrial structure is required by promoting renewable energy industry based on energy in the environment through enhanced usage of renewable energy source and reducing use of fossil fuels simultaneously.