Time-Dependent Emission Minimization in Sustainable Flow Shop Scheduling

It is generally accepted that global warming is caused by greenhouse gas emissions. Consequently, ecological aspects, such as emissions, should also be integrated into operative planning. The amount of pollutants emitted strongly depends on the energy mix and thus on the respective time period the energy is used. In this contribution we analyse the influence of fluctuating carbon dioxide emissions on emission minimization in flow shop scheduling. Therefore, we propose a new multi-objective MIP formulation which considers makespan and time-depending carbon dioxide emissions as objectives. Epsilon constraint method is used to solve the problem in a computational study, where we show that emissions can reduced by up to 10% if loads are shifted at times of lower CO₂ emissions.