Energy Consumption Models And Evaluation Method Of Energy Conservation Projects For Mechanical Manufacturing Enterprises

In China, energy has become one of strategy problems in economic development. Energy conservation is the inevitable choice in order to mitigate the conflict between growth and energy constraints. Mechanical manufacturing enterprises are one of important industries in national ecomony. And they are also one of important parts of energy conservation. Analysis and forecasting of energy consumption and evaluatin method of energy conservation projects for mechanical manufacturing enterprises are researched.Firstly, the characteristics of energy consumption of mechanical manufacturing enterprises are analyzed, including the number of energy consumption sectors and energy consumption equipments, kinds of energy consumed and the difference of energy consumption quantities and so on. Then energy conservation strategies including technology and management strategies are introduced.Secondly, an analysis model for mechanical manufacturing enterprises based on input-output theory is built in which the input and output variables are respectively energy consumed by an enterprise and energy consumption of production departments. Then, some applications of the anslysis model are introduced, including comparison of energy consumption in a enterprise, comparison of energy consumption in time direction in a enterprise, evaluation of energy consumption between enterprises and effect analysis of energy price to energy consumption in a enterprise.Besides, A BP neural networks (BPNN) model is presented for forecasting monthly energy consumption in mechanical manufacturing enterprises. The inputs of the model are monthly total running time of every kind of equipments, monthly total mass of every kind of products and monthly total labor hours of operators. The output of the model is monthly total consumption of every kind of energy. To asses the performance of BPNN, actual data are compared with BPNN and conventional regression model through analysis of variance (ANOVA).Thirdly, evaluation method of energy conservation projects under uncertain environment for mechanical manufacturing enterprises is proposed. The uncertain factors such as energy price and government decision are introduced, and the analysis method for uncertain factors is presented. Then evaluation indices including economical, technological, resource and environmental indices and the method for calculating their weights are proposed. The steps for evaluation of energy conservation projects under uncertain environment are described.Finally, a case study has been conducted to demonstrate how the energy consumpton models and evaluation method are applied to a mechanical manufacturing enterprise.