A novel two-stage mathematical model for green supplier development

Nowadays, numerous processes of any supply chain are done by suppliers and consequently they cause a massive amount of pollution released to the nature. Hence, greening the suppliers has become a necessity. Although most of green supplier development programs need high investment, formal optimization models that address this issue are very rare. This paper mainly aims to address this problem by introducing a two-stage mathematical model which can help managers allocate optimal investment in their suppliers. In the first stage, suitable green supplier development programs are selected. Then, a multi-objective optimization model is presented for investing in an appropriate set of green programs, concurrently. Moreover, the conceptual framework presented in this paper provides managerial insight in every step of this process. Also, a comprehensive analysis is done under two scenarios of budget estimation and it has been found that these programs highly influence their required investment, and therefore, they must be considered, simultaneously.