An integrated scheduling and control scheme with two economic layers for demand side management of chemical processes

AIChE Journal, vol. 71

Abstract

Abstract Integrated dynamic scheduling (IDS) and economic nonlinear model predictive control (eNMPC) enable economic operation of chemical plants subject to volatile energy prices. Herein, we combine the two concepts into an integrated two‐layer scheme. Therein, IDS performs “long‐horizon” scheduling on a day‐ahead (DA) market and eNMPC “short‐horizon” improvements on an intra‐day (ID) market. A case study demonstrates 5% economic savings over stationary operation. In contrast, stand‐alone IDS and eNMPC using DA prices reach 1% and 2.5% savings, respectively. We identify arbitrage as the main driver generating the additional benefit. Additionally, we compare our scheme to stand‐alone eNMPC in three ID price scenarios, where our approach consistently realizes savings of 5%. Conversely, eNMPC is price sensitive with variable revenue between 1% higher costs and 10% savings. Finally, requiring significantly shorter prediction horizons than stand‐alone eNMPC, our approach eases price forecasting and enhances real‐time capability.

Authors 4

1. Jan C. Schulze Aachen Process Systems Engineering (AVT.SVT)

   RWTH Aachen University

   Affiliation as printed

   Process Systems Engineering (AVT.SVT) RWTH Aachen University Aachen Germany

   Process Systems Engineering (AVT.SVT), RWTH Aachen University, Aachen, Germany

2. Chrysanthi Papadimitriou Aachen Process Systems Engineering (AVT.SVT)

   RWTH Aachen University

   Affiliation as printed

   Process Systems Engineering (AVT.SVT) RWTH Aachen University Aachen Germany

   Process Systems Engineering (AVT.SVT), RWTH Aachen University, Aachen, Germany

3. Paul Kolmer Aachen Process Systems Engineering (AVT.SVT)

   RWTH Aachen University

   Affiliation as printed

   Process Systems Engineering (AVT.SVT) RWTH Aachen University Aachen Germany

   Process Systems Engineering (AVT.SVT), RWTH Aachen University, Aachen, Germany

4. Alexander Mitsos corresponding Aachen Process Systems Engineering (AVT.SVT)

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   Energy Systems Engineering (ICE‐1) Forschungszentrum Jülich GmbH Jülich Germany

   JARA‐ENERGY Jülich Aachen Research Alliance Aachen Germany

   Process Systems Engineering (AVT.SVT) RWTH Aachen University Aachen Germany

   Process Systems Engineering (AVT.SVT), RWTH Aachen University, Aachen, Germany