中国工业部门的节能减排已取得成效，但仍面临重要挑战，需科学规划及实施节能减排路径。一方面应系统解析各项节能减排措施的作用机制，统筹节能、碳减排、污染减排和成本控制目标的协同效应及冲突关系开展路径高维多目标优化，传统单一目标管理易造成节能减排目标间的隐性转移；另一方面应识别工业节能减排管理效率空间差异，制定地市级节能减排实施路径，依据能耗及排放总量现状对目标简单分解难以充分挖掘各地市的潜力空间，造成节能减排路径整体成本上升。本研究采用自底向上建模方法，搭建集六项传统措施及新兴信息技术推广的钢铁、水泥、火电行业措施系统，并实现效益数值化表征；构建基于目标分解的NSGA-II-ELECTRE-III复合算法，形成上述三个行业2017-2035年的节能减排最优路径；建立大样本工业生产单元数据库，识别三个行业节能减排管理效率的空间差异并制定地市级节能减排实施路径，评估各地市潜力空间及经济成本。结果表明：（1）钢铁、水泥、火电行业可持续实现节能减排目标，幅度逐渐趋缓。2017-2035年三个行业的单位产品节能、碳减排、二氧化硫、氮氧化物及烟粉尘减排效益比重分别介于10.2-45.0%、19.0-67.2%和5.2-65.5%之间，对三个行业贡献最大的措施分别为主体工艺设备升级和清洁生产技术共同作用、行业规模调整、主体工艺设备升级；（2）各地市的节能减排管理效率与能耗/排放绝对量无直接关联。钢铁、水泥和火电行业节能减排管理效率较高地市分别为京津冀城市群、长江中下游城市群以及河套平原+东南沿海地市，均为行业的重点能耗/排放地区，基于各地市能耗及排放量简单分解路径难以充分拓展潜力空间；（3）实施路径可充分拓展各地市节能减排潜力空间。各地市实施路径的节能减排幅度差异显著，钢铁行业能耗/排放贡献前五地市的潜力空间介于23.3-64.2%之间，水泥与火电行业贡献前五地市相差超30%，表明能耗及排放现状；（4）钢铁、水泥行业实施路径综合成本低于火电行业。三个行业单位产品成本分别为56.87元/吨钢、5.5元/吨水泥和0.137元/kWh，分别约占产品售价的1.5%、0.8%和30%，分别有117、195和202个城市实施路径可取得正经济效益，占总节能减排潜力的61.5-81.1%、70.2-80.4%和21.3-25.6%。建议推广生物质燃料能源替代、低值二次能源共生利用、行业生产公共系统智能化等措施，并坚持“一市一策”精细管理模式，基于地区特征设定差异化的管理目标和重点推广措施，对实施路径成本较高地市提供适当财政支持。
The energy conservation and emission reduction in China’s industrial sector has achieved progress but still faces vital challenges, so it is necessary to scientifically plan and implement the energy conservation and emission reduction paths of the industries. On the one hand, the mechanism of the key industrial energy conservation and emission reduction measures should be systematically analyzed, and the many-objective optimization integrating the synergy and trade-off relationships among multiple objectives including energy conservation, carbon emission reduction, pollutant emission reduction and cost control should be carried out. The traditional management mode aiming at the single objective would easily lead to the implicit transfer among objectives. On the other hand, the spatial differences of the management efficiency of energy conservation and emission reduction should be recognized, to promote the different implementation paths for different cities. The simple decomposition method based on the status quo of energy consumption and pollution emission can not fully enlarge the potential space of the energy conservation and emission reduction in various cities, and leads to an increase in the total cost of implementing energy conservation and emission reduction paths.This study adopts the bottom-up modeling method to build an energy conservation and emission reduction measure system for China’s iron and steel, cement, and thermal power industries that integrates three types of six traditional measures and an emerging one, i.e. the promotion of information and communications technology, and realizes the quantification of their energy, environmental, and economic effects. To plan the the optimal path for energy conservation and emission reduction in the three industries from 2017 to 2035, this study constructs a compound algorithm integrating objective decomposition and NSGA-II-ELECTRE-III. In addition, a database of large-sample industrial production units is established, to identify the spatial differences of management efficiency and set the city-level implementation path, of which the energy conservation and emission reduction potential and economic cost are evaluated.The main results are as follows: (1) The iron and steel, cement, and thermal power industries can achieve the objectives of energy conservation and emission reduction with a tapering magnitude. From 2017 to 2035, the proportion of energy saving, carbon emission reduction, sulfur dioxide, nitrogen oxide and PM emission reduction benefits of the three industries is between 10.2-45.0%, 19.0-67.2%, and 5.2-65.5%, respectively. The measures that contribute the most to the three industries are the joint of the production equipment upgrade and cleaner production technology, the industry scale adjustment, and the production equipment upgrade; (2) The management efficiency of energy conservation and emission reduction in cities is not directly related to their energy consumption and emission amount. Cities with high management efficiency in three industries are distributed in the Beijing-Tianjin-Hebei urban agglomeration, the urban agglomeration in the middle-lower Yangtze River, and the Hetao Plain and southeast coastal cities, all of which are key energy consumption/emission areas. Simple decomposition paths based on the energy consumption/emissions can not fully expand the potential space; (3) The implementation path can fully expand the potential space of energy conservation and emission reduction in various cities. There are significant differences in energy conservation and emission reduction potential among cities. The potential ratios of the top five energy consumption/ emission cities of the iron and steel industry range between 23.3-64.2%, while the ones of the cement and thermal power industries are also more than 30%. (4) The comprehensive costs required for the implementation paths of the iron and steel and cement industries are lower than the thermal power industry. The specific costs of the three industries are 56.87 CNY/ton of steel, 5.5 CNY/ton of cement and 0.137 CNY/kWh, respectively. There are 117, 195, and 202 cities that can obtain net economic benefits in the three industries, respectively, accounting for 61.5-81.1%, 70.2-80.4% and 21.3-25.6% of the industry's total potential. It is recommended to promote measures such as biomass fuel application, symbiotic utilization of secondary energy with low calorific value, and the intelligentization of the public systems in the production process. It is suggested that the "one city, one policy" management mode should be adhered, as differentiated management objectives and key promotion measures should be set based on regional characteristics. In addition, appropriate financial support to cities with high implementation path costs should be provided.
