Improvement of Calculation Method of Heat Value of General Waste Using Two-stage Multiple Regression Analysis

—Case Study of Chiba Prefecture—

Abstract

General waste disposal is closely related to the lives of local residents, so the effective use of thermal energy generated at the time of incineration helps to prevent global warming and becomes a major return for local residents. In this research, to effectively utilize the thermal energy generated by burning general waste, we propose a method for predicting the heat value from occurrence factors using two-stage multiple regression analysis for a case study using Chiba Prefecture. In this two-stage multiple regression analysis, the objective variables of the first stage are used for the explanatory variables of the second stage. In the first stage, regression analysis is performed separately for household and business units, and in the second stage, regression analysis is performed for each facility unit. Pooled OLS and a random effects model were used for the analysis since fixed effects were not significant. To verify the validity of the prediction method, we calculated the correlation coefficient and performed the paired t test to compare the heat value obtained from the prediction method with the actual heat value measured. As a result, the correlation coefficient was 0.4216, which exceeds that which was considered to be correlated, 0.4. The results of the paired t test showed that the null hypothesis revealed no difference in mean at a significance level of 5%, and was therefore not rejected since the P-value was 0.5548. Therefore, our research verified the effectiveness of the method proposed for predicting the heat value from occurrence factors.