Feasibility analysis of energy system optimization for a typical manufacturing factory with environmental and economic assessments

To reduce fossil–fuel consumption and improve the efficiency of renewable energy usage in the manufacturing industry, several studies have investigated the environmental and economic impacts of integrated energy systems under various optimization scenarios. To analyze the cost–effectiveness of heat supply scenarios for a typical manufacturing industry using the photovoltaic (PV) technology and municipal solid waste incineration, herein, a metal–assembly paint factory was selected as the research target. The CO₂ emission and energy–consumption cost of a paint factory in 24 h are estimated as 31,229 kg and 12,314 CNY, respectively. Solar–to–Energy (StE(a–d)) and Waste–to–Energy (WtE) correspond to the nonenergy–storage, heat–storage, PV power–storage, PV technology's green power–procurement, and waste–incineration district heating scenarios, respectively. The results show that (1) under the nonenergy storage (StE(a)) scenario, the emissions of the paint factory can be reduced by 288 kg/24 h; however, the operation cost is increased by 1142 CNY/24 h (2) StE(b) has a better economic performance (cost reduction by 2472 CNY/24 h) than StE(c) (cost increased by 1546 CNY/24 h). Additionally, the reduction in the CO₂ emissions in StE(b) (12,057 kg/24 h) is considerably higher than that of StE(c) (7644 kg/24 h). (3) In the case of sufficient energy supply, StE(d) (24,361 kg/24 h) reduces CO₂ emissions more effectively, followed by WtE (CO₂–emission reduction = 17,994 kg/24 h), than the other scenarios (for a paint factory). However, from the perspective of cost reduction, WtE showed to have a more outstanding performance (cost reduction 1428 CNY/24 h).