Analysis of waste-to-energy conversion efficiencies based on different estimation methods in Seoul area

Although waste-to-energy (WtE) may reduce the amount of waste disposed and recover the heat in the form of electricity or steam, it has limitations in terms of stable energy resources due to uneven waste properties and variation in waste generation and heat requirements by season. The purpose of this study was to analyze the energy production and actual utilization in resource recovery facilities and to secure the preliminary data for its efficient utilization. Four WtE plants were investigated in Seoul metropolitan area. This study analyzed the heat recovery efficiency of each WtE plant using different estimation formula. As a result, that of facility A was 0.74 by Korea's energy efficiency method, which was the highest among the WtE plants. In facility D, energy loss was the highest due to a mismatch of pollution control facilities. It means energy recovery efficiency could be improved through optimization of treatment processes and final energy utilization. In summer, energy is being wasted by steam throwaway, because heat demand is relatively low compared to other seasons. Thus, the alternative application like district cooling needs to be considered to improve energy efficiency as well as other private businesses or district heating using additional steam.