Study on the policy of replacing coal-fired boilers with gas-fired boilers for central heating based on the 3E system and the TOPSIS method: A case in Tianjin, China

The high energy consumption and heavy air pollution caused by heating in winter have become increasingly severe in China in recent years. The policy of replacing coal-fired boilers with gas-fired boilers for central heating is of great significance to the sustainable development of China. This paper incorporates the factors involved in the policy into the energy-environment-economy (3E) system and transforms it into a multi-objective optimization problem. Combining with the technique for order preference by similarity to an ideal solution, an acceptable and reasonable solution that can make the 3E system benign and economically profitable is obtained. Especially, grasping the appropriate proportion of clean heating and providing subsidies to heating enterprises are the keys for the government to implement the policy in a step-by-step manner to achieve good environmental and economic benefits. Taking Tianjin as an example, relevant works are carried out to study the demand for natural gas after the implementation of the policy, the investment cost of heating companies, the subsidy amount of government and gas emissions. The paper suggests that the proportion of heating by the gas-fired boiler is 34.7-35.7% and the subsidy price varies from 0.75 to 1.50 yuan/m(3), which provides a reference for decision-making agencies. (C) 2019 Elsevier Ltd. All rights reserved.