MPC-based Electric Energy Storage Sizing for a Net Zero Energy Factory

The increasing penetration of Renewable Energy Source (RES) makes consumption flexibility one of the major requirements to maintain electric grid stability. A key role in effectively matching volatile RES production with load demand can be played by manufacturing enterprises, as they offer a few flexibility options. The aim of this work is from one side to develop a new control algorithm for increasing the flexibility and from the other side to identify and evaluate new flexibility options within manufacturing enterprises, with the aim to move towards the concept of Net-Zero-Energy Factories. A Model Predictive Control strategy, featured with a Mixed-Integer-Linear-Programming algorithm, has been implemented to optimally scheduling the production of a furniture industry. A sensitivity analysis on buffer stocks dimension is carried out in order to identify the optimal storage sizing (for material and energy) allowing to minimize the net yearly energy exchange with the grid. The studied approach allows to reduce by 27% the total energy exchange with the grid with respect to a baseline case study. Further decrease of 50 % has been obtained with the introduction of a battery storage system.