Mathematical programming approach to productivity improvement in wind turbine-blade manufacturing through a case study

Wind energy has attracted remarkable attention in recent years as one of the most important renewable energy sources. However, wind energy production is still a costly process and one of the reasons is production processes which are usually not optimized. The purpose of this paper is to improve the efficiency of spar cap production process as an important phase of a wind turbine blade production in a manufacturing system. For this purpose, the present paper introduces a new optimization problem for optimal assignment of fiberglass rolls along the spar cap. In order to solve the roll allocation problem (RAP) optimally, two alternative mathematical programming models based on mixed-integer programming (MIP) and constraint programming (CP) are developed. Subsequently, two cases form a real manufacturing setting are presented and solved by using both MIP and CP models. Although proposed models are capable to solve problems optimally, it is observed that CP outperforms MIP. Solving RAP optimally reduces walking time/distance of workers considerably and provides significant improvements in comparison with current manufacturing practices. Besides, the total operation time will also decrease correlatively, and this will lead to an increase in productivity of turbine blade production in the studied system