A Multi-objective Scheduling Model for a Gas-Steam-Electricity Coupling System in the Steelwork Based on Time-of-Use Electricity Pricing

By-product gas, steam, and electricity coupling system plays an important role in providing stable energy supply for steelworks. In this paper, a multi-period GSECS scheduling model with the objectives of economics and in-plant grid reliability was constructed. Economics is reflected in the reduction of gasholder penalty cost, electricity interaction cost, and carbon emission cost while the reliability is shown as the variance of the electric load. In GPC, a new method of defining gasholder penalty factor was designed to distinguish different types and operating intervals of gasholders. The NSGA-II was used to obtain the multi-objective Pareto solution set, and the optimal solution was filtered based on the improved AHP—entropy weight method. With a calculated example, compared to manual operations, the gasholder penalty cost was reduced by − 51.37% after optimization, as well as a reduction of 25.23% in the deviation of the gasholder, enhancing its stability. In addition, the variance of the in-plant grid was improved by 45.15%.